Entries |
Document | Title | Date |
20080205259 | Recursive equalization matrix for multiple input multiple output systems - A method for receiving a signal in a wireless communication system based on Multiple-Input Multiple Output (MIMO)—Orthogonal Frequency Division Multiplexing (OFDM) through multiple antennas. In the system, weight for a zero forcing based equalization matrix is determined by inverting a channel transfer matrix for each subcarrier of the signals. The original data transmitted is recovered by combining data subcarriers from different receive antennas using the calculated weights thus reducing the system complexity. | 08-28-2008 |
20080205260 | SYSTEM AND METHOD FOR TRANSMITTING DATA BURSTS IN COMMUNICATION SYSTEMS - Disclosed is a method for transmitting data bursts by a base station in a communication system, including forming one group which includes at least one subchannel and transmitting at least two data bursts having an equal transmission characteristic through each subchannel included in the group. | 08-28-2008 |
20080225689 | Orthogonal frequency division multiplexing having tones with overlaid data and pilot symbols - In one embodiment, an OFDM transmitter generates sets of frequency-domain data symbols from a stream of digital data. For each set of frequency-domain data symbols generated, the transmitter generates a corresponding set of frequency-domain pilot symbols. Each corresponding set of data symbols and pilot symbols are then multiplexed onto a set of frequency tones, such that, at least one tone is occupied by both a data symbol and a pilot symbol. For each tone having both a pilot symbol and data symbol, the pilot symbol and data symbol are added together to form an overlaid data and pilot (ODP) tone. Each set of tones having at least one ODP tone is then transmitted to an inverse fast Fourier transform (IFFT) processor that transforms each set of tones into an ODP OFDM symbol. Each ODP OFDM symbol is then prepared for transmission using digital-to-analog conversion, cyclic prefix insertion, and RF modulation. | 09-18-2008 |
20080232236 | METHOD AND APPARATUS FOR CHANNEL ESTIMATION OF OFDM WITH FREQUENCY INSERTED PILOTS - In an OFDM system having guard intervals interposed between symbols or frames, and having pilot signals distributed within the symbols or frames, a method for channel estimation is provided. The method comprising the steps of: in the time domain, performing an operation to obtain only a set of received pilots; and sectionalizing or subdividing the set of received pilots into a plurality of sub-sections; whereby a refined channel estimation is obtained on a sub-sectional basis. | 09-25-2008 |
20080232237 | METHOD AND APPARATUS FOR ROBUST TIMING RECOVERY OF OFDM SYSTEM FOR FAST FADING CHANNELS - In an orthogonal frequency division multiplex (OFDM) communication system, a method comprising the step of performing time estimation in a time domain. | 09-25-2008 |
20080232238 | Method and system for robust, secure, and high-efficiency voice and packet transmission over ad-hoc, mesh, and MIMO communication networks - Using at least one MIMO-capable transceiver allows weighting calculations for signals transmitted and received, and enables individual packets to adapt, in a scalable, flexible, and responsive fashion to the real-world dynamics of a continuously varying communications network environment. The method and system of this invention use adaptively-derived diversity means to rapidly and efficiently distinguish the desired signal from noise, network interference, and external interference impinging on the network's transceivers and can transmit with lessened overhead. ADC operations and signal transformations continuously update combiner weights to match dynamically-varying environmental and traffic conditions, thereby continuously matching necessitated signal and waveform transformations with environmental and signal effects and sources. Successive iterations of the adaptation algorithm let each node's multiport combiner and distribution weights approach the MIMO channel's Shannon capacity in high-rate networks, or to minimize power needed to close links at a specified rate in low-rate networks, e.g. Voice-Over-IP networks. | 09-25-2008 |
20080247307 | Method, Apparatus And System For Detecting Mode And Guard Interval - The present invention is directed to a method, apparatus and system for detecting the mode and the guard interval of a received orthogonal frequency division multiplexing (OFDM) symbol, which includes a guard interval with length N | 10-09-2008 |
20080267058 | Optimum technique for encoding and decoding physical resource block locations - An apparatus, such as a user equipment, includes a resource unit RU measurement unit coupled to an output of a wireless receiver; an encoder configurable to encode information descriptive of M perceived best ones of N RUs, where each individual RU is assigned a unique number from a set | 10-30-2008 |
20080273453 | Methods and systems for channel estimation in a collaborative Multi Input Multiple Output (MIMO) communication system - Methods and systems for estimating channel of one or more MSs in a collaborative MIMO communication system are provided. The method includes receiving a signal transmitted from a transmit antenna of a first MS and a transmit antenna of a second MS at a BTS using one or more receiver antennas. The method further includes computing one or more conjugate products for each of the first MS and the second MS using the signal. Thereafter, an average is determined over the plurality of receiver antennas and the plurality of tiles of the plurality of conjugate products for each of the first MS and the second MS. A phase determined based on the average of the plurality of conjugate products for the first MS and the second MS is divided into a first phase and a second phase for each of the first MS and the second MS. Additionally, the method includes determining a channel estimate for each tile of the first MS and the second MS at each receiver antennas. The method further includes performing predefined computations on the channel estimate of each tile of the first MS and the second MS at each receiver antenna of the BTS using the corresponding first phase and the corresponding second phase. | 11-06-2008 |
20080285434 | System, Apparatus, and Method for Spatial Multiplexing with Symbol Spreading - The present invention provides a system ( | 11-20-2008 |
20080291817 | TIMING ESTIMATION IN AN OFDM RECEIVER - A timing estimation system and methodology are provided. In particular, a first pilot is employed in conjunction with three acquisition stages. In the first stage, an attempt is made to observe the leading edge of the correlation curve associated with the first pilot symbol. In the second stage, a determination is made to confirm a leading edge was detected in the first stage by attempting to observe a trailing edge of the correlation curve. Furthermore, during this second stage, a frequency loop is updated to account for frequency offset. The third stage is for observing the trailing edge of the curve if it was not already observed in stage two. Upon detection of receipt of the first pilot, a second pilot can subsequently be employed to acquire fine symbol timing. | 11-27-2008 |
20080291818 | Radio communication system - A radio communication receiver which includes an antenna array having at least two antennas to provide antenna diversity. The receiver is for receiving signals containing orthogonally coded data sub-streams derived from a source data stream. The receiver also has receiver circuitry, coupled to the antenna array, having a detection stage to detect the data sub-streams and a combiner stage for combining the detected data sub-streams to recover the source data stream. Each antenna has an electrically insulative core of solid material having a dielectric constant greater than 5. Each antenna also has a three-dimensional antenna element structure disposed on or adjacent the outer surface of the core. | 11-27-2008 |
20080291819 | SOFT-BIT DE-MAPPING DEVICE AND METHOD OF GENERATING SOFT BITS FOR DECODING - A soft-bit de-mapping device and method of generating soft bits for decoding quantizes a log-likelihood ratio (LLR) value for a received value using functions bits and channel parameter bits to generate the soft bits. The function bits are generated by quantizing an LLR function for the received value, which includes modifying an original curve of the LLR function to a modified curve such that a segment of the original curve with the lowest slope is protected in the modified curve for a fixed equal quantization step-size. The channel parameter bits are generated by quantizing a channel parameter for the received value to generate channel. | 11-27-2008 |
20080298226 | Vehicular communication device and control information generating device - A vehicular communication device switches over a communication method between the OFDM method and the SS method. A PLC master set includes a LAN communication unit for performing data communications with control units such as an engine control ECU via an in-vehicle LAN. In the PLC master set, a microcomputer acquires the operating states of parts of the vehicle from various control units through the LAN communication unit, and uses the acquired operating states and control information stored previously to enable data communications without being affected by noises occurring in the parts of the vehicle by notifying a PLC slave set of a communication method in the PLC communication unit and a communication method with a sub-carrier set prohibited from use being set when a communication method is the OFDM method. | 12-04-2008 |
20080316909 | COHERENT DETECTION FOR DIFFERENTIALLY ENCODED OFDM SYSTEMS - A method and system for coherent detection in which a OFDM symbol is multiplied by the complex conjugate of the previous OFDM symbol, which is obtained by one OFDM symbol delay and a complex conjugation circuit. This soft decision is passed through a QPSK slicer to obtain a hard decision. The soft decision is then divided by the hard decisions. The channel phase change between the two OFDM symbols is then obtained. For the first OFDM symbol, the channel is computed. A channel estimate for each ODFM symbol is computed from corresponding channel estimates and channel phase difference estimates. The channel phase difference between each two OFM symbols is computed. The channel phase difference is passed through an exponent operation and multiplied by the soft decision to obtain a refined soft decision that is then passed through another QPSK slicer to obtain the final hard decision. | 12-25-2008 |
20080316910 | Complex vector quantization codebook for use in downlink multi-user MIMO mobile broadcast systems - A wireless communications device having a complex vector quantization codebook for use in a downlink multi-user MIMO (multiple-input-multiple-output) mobile broadcast system with feedback enables the interference between data simultaneously sent by the base station to a plurality of mobile terminals to be reliably minimized. The codebook contains many subsets of code vectors that are substantially mutually (i.e., pairwise) orthogonal, or almost orthogonal, to each other. With use of such a codebook, a base station can transmit simultaneously to subsets of mobile terminals associated with these subsets of code vectors with minimal interference therebetween. | 12-25-2008 |
20090010148 | METHOD AND DEVICE FOR REPORTING, THROUGH A WIRELESS NETWORK, A CHANNEL STATE INFORMATION BETWEEN A FIRST TELECOMMUNICATION DEVICE AND A SECOND TELECOMMUNICATION DEVICE - The present invention concerns a method for reporting, through a wireless network, a channel state information between a first telecommunication device which comprises M | 01-08-2009 |
20090010149 | VIRTUAL MULTI-ANTENNA METHOD FOR OFDM SYSTEM AND OFDM-BASED CELLULAR SYSTEM - Provided are a virtual multi-antenna method for an orthogonal frequency division multiplexing (OFDM) system and an OFDM-based cellular system. The virtual multi-antenna method includes grouping sub-carriers in a frequency domain of an OFDM symbol and generating at least one group including G sub-carriers; and regarding the G sub-carriers included in the at least one group as multiple channels used in a multi-antenna technique and virtually applying the multi-antenna technique to the transmission and reception of the OFDM symbol. The virtual multi-antenna method can effectively reduce an interference signal and obtain the effects of a spatial division multiple access (SDMA) technique without physically using multiple antennas. | 01-08-2009 |
20090059783 | Communication system and method of receiving high priority signals and low priority signals - A communication system and method of communicating signals to a plurality of different types of receivers is provided. The communication system includes at least one transmitter that transmits a high priority signal and a low priority signal that are hierarchically modulated and transmitted as a single frequency network. At least one satellite receives and re-transmits at least one of the high priority and low priority signals. At least one of the plurality of receivers include a processor that performs the steps of storing the hierarchically modulated signal, demodulating the high priority signal from the hierarchically modulated signal, decoding the demodulated high priority signal, re-encoding the high priority signal, and processing the stored hierarchically modulated signal based upon the re-encoded high priority signal. | 03-05-2009 |
20090067318 | SYSTEMS AND METHODS FOR DESIGNING A REFERENCE SIGNAL TO BE TRANSMITTED IN A MULTIPLEXED CELLULAR SYSTEM - A method for designing a reference signal to be transmitted in a multiplexed cellular system is described. A first set of matrices that comprises a plurality of matrices is selected. An optimal partition of the first set of matrices is determined. A third matrix is formed. The third matrix represents a cross-correlation of a second matrix and each of the plurality of first matrices. A minimum corresponding to the first set of matrices is set. The second matrix is updated using the minimum corresponding to the first set of matrices. Each column of the second matrix is scaled by a first value. | 03-12-2009 |
20090073869 | Novel receiver architecture for pilot based OFDM systems - The invention relates to a novel methodology and apparatus for clock-offset compensation and common-phase offset correction in Frequency Division Multiplixing based wireless local area network (WLAN) environment, such as an Orthogonal Frequency Division Multiplexing (OFDM) environment. A curve fit, such as a threshold-based, least mean squares (LMS) fit of phase of the pilot sub-carriers in each OFDM symbol is used to estimate and counteract the rotation of the data sub-carriers due to residual frequency offset, low frequency phase noise, and clock offset. The invention is particularly well suited to wireless channels with multipath where pilots typically undergo frequency-selective fading. The thresholding LMS is implemented in a hardware-efficient manner, offering cost advantages over a weighted-LMS alternative. Additionally, the invention uses a unique phase-feedback architecture to eliminate the effects of phase wrapping, and avoid the need to refine channel estimates during packet reception. | 03-19-2009 |
20090086618 | Amplitude Attenuation Estimation and Recovery Systems for OFDM Signal used in Communication Systems - This disclosure relates to amplitude correction for orthogonal frequency division multiplexing signals received by a communication device. An amplitude attenuation estimation is performed for amplitude correction on received OFDM signals. | 04-02-2009 |
20090086619 | Ultra-Wideband Communication Protocol - A communication protocol for ultra-wideband communications is provided. The present invention provides compatibility and interoperability between ultra-wideband communications devices within various types of networks. In one embodiment, combined, or interleaved data frames having both high and low data transfer rate capability are provided. The low data transfer rate may be used for initial discovery of the type of network that is being accessed, and the high data transfer rate may be used to quickly transfer data within networks that have a high data transfer rate capability. This Abstract is provided for the sole purpose of complying with the Abstract requirement rules that allow a reader to quickly ascertain the subject matter of the disclosure contained herein. This Abstract is submitted with the explicit understanding that it will not be used to interpret or to limit the scope or the meaning of the claims. | 04-02-2009 |
20090092038 | TIMING-OFFSET ESTIMATION IN MODULATED SIGNALS USING WEIGHTED CORRELATION VALUES - In one embodiment, a timing-offset estimator calculates a correlation value for each sample of an OFDM signal having a cyclic prefix for each OFDM symbol. The correlation value is provided to a tapped delay line that applies a separate weight to each of 2V correlation values, where V is the length of the cyclic prefix and the weights are based on a triangular weighting scheme that increases linearly from the first value, peaks at the V | 04-09-2009 |
20090092039 | Method and system for formation and communication of information frames in wireless communication systems - A method and system for wireless transmission of information is provided. Such wireless transmission of information involves constructing a payload unit for data, appending a preamble to the payload unit, wherein the preamble comprises a PHY preamble including a MAC header for the payload unit, and transmitting at least the preamble of the payload unit over a wireless channel. | 04-09-2009 |
20090092040 | METHODS AND SYSTEMS FOR SELECTING MODULATION IN AN ORTHOGONAL FREQUENCY DIVISION MULTIPLEXING SYSTEM - Methods and systems for selecting modulation in an orthogonal frequency division multiplexing system are provided. In one embodiment, a method for a remote unit of an OFDM multipoint-to-point communications system comprises: establishing communication between a first remote unit and a host unit, the first remote unit and a plurality of remote units communicatively coupled to the host unit in a multipoint-to-point configuration; transmitting a plurality of tones from the first remote unit such that tones from the first remote unit and at least one other remote unit are simultaneously received at the host unit, the plurality of tones modulated with upstream information using OFDM; modulating up to a plurality of tones using a first modulation scheme when transmitting a first type of upstream information; and modulating up to a plurality of tones using a second modulation scheme when transmitting a second type of upstream information. | 04-09-2009 |
20090097396 | METHOD AND APPARATUS FOR TRANSMITTING/RECEIVING A CONTINUOUS PILOT CODE IN A MULTI-CARRIER SYSTEM - The present invention provides a method for transmitting/receiving a continuous pilot code in a multi-carrier system. The method for transmitting comprises: performing a time-frequency domain two dimensional encoding on an information bit stream to be transmitted; mapping the encoded bit stream to obtain a continuous pilot carrying encoding information; multiplexing a load, a discrete pilot and the mapped continuous pilot carrying the encoding information based on distribution of the load, the discrete pilot and the continuous pilot on a sub-carrier, to generate a frequency domain signal; and performing a frequency-time domain transforming on the generated frequency domain signal, to obtain a time domain sample. The method for receiving comprises: extracting the continuous pilot from an active carrier of a multi-carrier signal; and performing a time-frequency domain decoding on the extracted continuous pilots to obtain the decision of transmitted information bits. The invention ensures reliable transmission of the information without using additional bandwidth resource by carrying information in the continuous pilots using an encoding scheme. | 04-16-2009 |
20090116375 | METHOD AND APPARATUS FOR SPACE-TIME CODING AND DECODING - The present invention relates to methods for space-time coding and decoding in a wireless communication system with multiple antennas including: generating an orthogonal matrix according to signals to be transmitted; generating a coefficient matrix corresponding to the orthogonal matrix according to channel status information received; and generating a transmission matrix according to the orthogonal matrix and the coefficient matrix; performing a weight-combination for received signals according to channel status information in a receiver; and obtaining estimations of transmitted signals corresponding to the received signals by performing detection for the received signals. The present invention also provides apparatuses for space-time coding and decoding. By applying the present invention, the bit error rate of a system is reduced and bit error performance of the system is improved. And the transmission rate of the system is increased remarkably when there are more than one complex signals to be transmitted. | 05-07-2009 |
20090129257 | SYSTEM AND METHOD FOR COMPENSATION OF NON-LINEAR TRANSMITTER DISTORTION - A system, apparatus, method and article to provide compensation of non-linear transmitter distortion are described. The apparatus may include a receiver node ( | 05-21-2009 |
20090129258 | TRANSMISSION OF SIGNALLING INFORMATION IN AN OFDM COMMUNICATION SYSTEM - An Orthogonal Frequency Division Multiplexing, OFDM, transmitter comprises a signalling data generator ( | 05-21-2009 |
20090147668 | Orthogonal pilot code construction - A method, system and apparatus for communication in an Orthogonal Frequency Division Multiplexing (OFDM) communication system is provided. The method includes allocating a plurality of sequences to a plurality of sectors in the OFDMA communication system. The plurality of sequences are orthogonal to each other. The method further includes communicating one or more OFDM tiles between one or more MSs in one or more sectors of the plurality of sectors and one or more BSs of the one or more sectors. The one or more OFDM tiles include one or more sequences of the plurality of sequences allocated to the one or more sectors. | 06-11-2009 |
20090168641 | METHOD AND CIRCUIT FOR FREQUENCY OFFSET ESTIMATION IN FREQUENCY DOMAIN IN THE ORTHOGONAL FREQUENCY DIVISION MULTIPLEXING BASEBAND RECEIVER FOR IEEE 802.11A/G WIRELESS LAN STANDARD - A method for frequency offset estimation in frequency domain is provided. The method comprises the following steps. First, a phase angle of a signal field of the input signal after processed by Fast Fourier Transformation (FFT) and channel equalization is calculated. A frequency offset error originated from at least one frequency offset estimation process in time domain is then estimated according to the phase angle. | 07-02-2009 |
20090175160 | Precoder Matrix for Multichannel Transmission - This invention describes a method for precoding in a transmitter utilizing a multichannel transmission, using a precoder for, e.g., M-QAM (M>4) modulated OFDM systems. The invention describes a new precoding method that is suitable for use, e.g., in an MB-OFDM UWB system especially when targeting for high data rates (above 480 Mbps). This may involve transmitting 16-QAM in place of 4-QAM symbols. The method could be adopted also for some future wireless LANs (local area networks), for future evolutions of 3G and for 4G systems. | 07-09-2009 |
20090196164 | METHOD AND APPARATUS FOR CLOSED LOOP TRANSMISSION - In a wireless communication system, a method and apparatus for closed loop transmission is disclosed. In accordance with the preferred embodiment of the present invention, a time frequency portion of an uplink frame is dynamically reserved as a sounding zone for uplink channel sounding. A first message is transmitted to a first subscriber station in a downlink frame assigning a time-frequency resource within the sounding zone, and a sounding waveform. Furthermore, a signal is received from the subscriber station within the assigned time-frequency resource, a partial channel response is determined from the received sounding signal, and the subsequent transmission to the subscriber station is tailored based on the at least partial channel response. | 08-06-2009 |
20090196165 | TRANSMITTING AND RECEIVING APPARATUSES AND METHODS - A transmitting apparatus which transmits a transmit symbol in orthogonal-frequency division multiplexing (OFDM) is disclosed. The transmitting apparatus includes a unit which provides a unicast channel; a unit which provides a multimedia broadcast multicast service (MBMS) channel; a unit which provides a specific pilot channel which is specific to a specified cell; a unit which provides one or more common pilot channels common to a plurality of cells; and a multiplexing unit which multiplexes the unicast channel, the MBMS channel, the specific pilot channel, and the one or more common pilot channels, and creates the transmit symbol, wherein the multiplexing unit time-division multiplexes, in the same frequency band, a unicast frame which includes the unicast channel, and an MBMS frame which includes the MBMS channel, and wherein an insertion density of the common pilot channel included in the MBMS frame is larger than an insertion density of the specific pilot channel included in the unicast frame. | 08-06-2009 |
20090201795 | SIGNALING METHOD IN AN OFDM MULTIPLE ACCESS SYSTEM - A method for reducing the peak-to-average ratio in an OFDM communication signal is provided. The method includes defining a constellation having a plurality of symbols, defining a symbol duration for the OFDM communication signal, and defining a plurality of time instants in the symbol duration. A plurality of tones are allocated to a particular communication device, and a discrete signal is constructed in the time domain by mapping symbols from the constellation to the time instants. A continuous signal is generated by applying an interpolation function to the discrete signal such that the continuous signal only includes sinusoids having frequencies which are equal to the allocated tones. | 08-13-2009 |
20090213723 | METHOD FOR UPLINK TRANSMISSION IN OFDM(A) SYSTEM - A method for uplink transmission in an OFDMA system is provided. The subcarrier transmission method includes arranging 4 pilot REs at different positions of a frequency axis in a basic unit when the basic unit includes 4 subcarriers on the frequency axis and 6 OFDM(A) symbols in a time axis, arranging data REs at remaining positions of the basic unit, and transmitting the basic unit to a receiving end. | 08-27-2009 |
20090219800 | Transmission Method with Optimal Power Allocation Emitted for Multicarrier Transmitter - A transmission method ( | 09-03-2009 |
20090231991 | TRANSMITTER APPARATUS, RECEIVER APPARATUS, TRANSMITTING METHOD, RECEIVING METHOD, AND PROGRAM - A serial-parallel converter | 09-17-2009 |
20090238063 | METHODS AND APPARATUS FOR DIVERSITY COMBINING OF REPEATED SIGNALS IN OFDMA SYSTEMS - In accordance with a method for diversity combining in an orthogonal frequency division multiple access (OFDMA) system, repetition diversity equalization and combining may be performed with respect to received OFDMA signals. In addition, receiver antenna diversity equalization and combining may be performed with respect to the received OFDMA signals. The repetition diversity equalization and combining and the receiver antenna diversity equalization and combining may be performed in accordance with a maximum ratio combining (MRC) scheme. | 09-24-2009 |
20090238064 | METHOD OF TRANSMITTING REFERENCE SIGNAL AND TRANSMITTER USING THE SAME - A method and apparatus of transmitting a reference signal in a wireless communication system is provided. A reference signal sequence is generated by using a pseudo-random sequence. A portion or entirety of the reference signal sequence is mapped to at least one resource block and is transmitted. The pseudo-random sequence is generated by a gold sequence generator which is initialized with initial values obtained by using cell identifier. The reference signal provides low PAPR and high cross correlation characteristic. | 09-24-2009 |
20090238065 | SYSTEM AND METHOD FOR CONTENTION BASED TONES IN A MULTIPOINT-TO-POINT ORTHOGONAL FREQUENCY DIVISION MULTIPLEXING SYSTEM - Systems and methods for round-trip-delay adjustment in a multipoint-to-point orthogonal frequency division multiplexing (OFDM) system are provided. In one embodiment, a method for a remote unit to request bandwidth in an Orthogonal Frequency Division Multiplexing (OFDM) multi-point to point system comprises: transmitting a signal from a remote unit having a request for bandwidth to a host unit on a first tone, the signal from the remote unit configured to combine with a signal from at least one other remote unit on a different tone to form a coherent OFDM waveform; determining when a collision has occurred on the first tone between the signal transmitted by the remote unit and a signal from at least one other remote unit; and when a collision occurs, re-transmitting the request for bandwidth on the first tone. | 09-24-2009 |
20090245084 | SYSTEM AND METHOD FOR COMMUNICATING DATA USING EFFICIENT FAST FOURIER TRANSFORM (FFT) FOR ORTHOGONAL FREQUENCY DIVISION MULTIPLEXING (OFDM) - A system communicates data and includes a transmitter for transmitting a communications signal that carries communications data. It includes an efficient modulator for approximating the frequencies of sine/cosine basis waveforms using complex exponential functions and adding and subtracting the complex exponential functions to generate an Orthogonal Frequency Division Multiplexed (OFDM) communications signal as a plurality of N data subcarriers that carry communications data as data symbols. A receiver receives the OFDM communications signal and includes a demodulation circuit for demodulating the OFDM communications signal using logical shifts of multiples +/−2 | 10-01-2009 |
20090245085 | Graph-Based Method for Allocating Resources in OFDMA Networks - A method allocates radio channel resources in an orthogonal frequency-division multiple access network including a set of base stations (BS) and a set of mobile stations (MS). For each BS, a diversity set is maintained for the sets of MS. Each BS determines possible interference at the MS based on the diversity set. A graph is constructed, in which nodes represent the sets of MS, mid each edge between a pair of nodes represents channel interference between the MS represented by the pair of nodes. A weight is assigned to each edge, which reflects interference between the two MSs connected by the edge. The interference graph is partitioned into non-overlapping clusters of nodes based on a structure of the interference graph, the potential interference, so that a sum of the weights of the edges between each cluster is maximized. Based upon the graph partitioning, the channel resources are allocated to the mobile stations in order to maximize the system capacity. | 10-01-2009 |
20090245086 | Graph-Based Method for Allocating Resources in OFDMA Networks - A method allocates radio channel resource in an orthogonal frequency-division multiple access network including a set of base stations (BS) and a set of mobile stations (MS). For each BS, a diversity set is maintained for the sets of MS. Each BS determines possible interference at the MS based on the diversity set. A graph is constructed, in which nodes represent the sets of MS, and each edge between a pair of nodes represents channel interference between the MS represented by the pair of nodes. A weight is assigned to each edge, which reflects interference and signal strength on the subchannel between the two MSs connected by the edge. Channel resources are allocated to the MS based on the graph. | 10-01-2009 |
20090245087 | Slow Speed Mute Resistance Via Selective COFDM Bin Loading - Systems and methods are presented for improving the ability to withstand slow speed mute via diversity transmission while avoiding loss in link level margin. In exemplary embodiments of the present invention, systems and methods are presented for improving resistance to slow speed muting by employing transmit diversity where a second signal is not a replica of the original signal. The second signal can be generated, for example, by using only a COFDM FFT bin that contained the cluster sync bit while setting all other bins to zero. That is, only the spectral portion of interest of the COFDM signal need be utilized. In such exemplary embodiments, the same frequency and time delay offset can be used as in current systems and methods, except that the replica COFDM signal can, for example, consist of only one populated FFT bin. | 10-01-2009 |
20090257342 | Resource block based pilot pattern design for 1/2 - stream mimo ofdma systems - In OFDMA wireless communications systems, pilot pattern design is optimized based on predefined resource block size. The number of pilots and the spacing between pilots within a resource block is determined based on a set of system requirements. In one novel aspect, pilots are allocated within a resource block to avoid channel extrapolation in both frequency domain and time domain. First, four pilots are positioned at four corners of the resource block. Next, the remaining pilots are maximally evenly distributed within the resource block along both the frequency domain and the time domain. Finally, it is verified that an approximately equal number of pilots are evenly distributed along the time domain with respect to each data stream to minimize power fluctuation. For uplink transmission, one or more frequency tones at one or more edges of the resource block are reserved to be pilot-free to reduce multiuser synchronization error effect. | 10-15-2009 |
20090257343 | PERMUTING SLOTS TO LOGICAL DISTRIBUTED RESOURCE UNITS - Various example embodiments are disclosed. According to an example embodiment, a method may comprise sending, by a sending wireless station in a wireless network, data to a receiving wireless station, the data being sent via at least one logical distributed resource unit (LDRU), the LDRU including slots included in at least one physical resource unit (PRU), each of the slots included in the at least one PRU being associated with a different orthogonal frequency division multiple access (OFDMA) symbol and a different OFDMA subcarrier. | 10-15-2009 |
20090262641 | SIGNALING METHOD IN AN OFDM MULTIPLE ACCESS SYSTEM - A method for reducing the peak-to-average ratio in an OFDM communication signal is provided. The method includes defining a constellation having a plurality of symbols, defining a symbol duration for the OFDM communication signal, and defining a plurality of time instants in the symbol duration. A plurality of tones are allocated to a particular communication device, and a discrete signal is constructed in the time domain by mapping symbols from the constellation to the time instants. A continuous signal is generated by applying an interpolation function to the discrete signal such that the continuous signal only includes sinusoids having frequencies which are equal to the allocated tones. | 10-22-2009 |
20090268602 | METHOD OF GENERATING CODE SEQUENCE AND METHOD OF TRANSMITTING SIGNAL USING THE SAME - A method of generating a code sequence and method of adding additional information using the same are disclosed, by which a code sequence usable for a channel for synchronization is generated and by which a synchronization channel is established using the generated sequence. The present invention, in which the additional information is added to a cell common sequence for time synchronization and frequency synchronization, includes the steps of generating the sequence repeated in time domain as many as a specific count, masking the sequence using a code corresponding to the additional information to be added, and transmitting a signal including the masked sequence to a receiving end. | 10-29-2009 |
20090274035 | Dynamic Interleaving Method and Device - An interleaving method ( | 11-05-2009 |
20090274036 | HARQ BASED ICI CODING SCHEME - Method and apparatus for transmitting data in an OFDM communication system, the method including transmitting over a channel, an original data packet that includes original data, the original data packet including at least one modulated data symbol encoded onto at least one sub-carrier using a first coding scheme. The method further includes transmitting a retransmitted data packet corresponding to the original data packet in response to a non-acknowledgement (NACK), the retransmitted data packet including a copy of the original data packet wherein the at least one modulated data symbol is encoded onto the at least one sub-carrier using a second coding scheme. | 11-05-2009 |
20090274037 | METHOD FOR MAPPING PHYSICAL HYBRID AUTOMATIC REPEAT REQUEST INDICATOR CHANNEL - A method for mapping a physical hybrid automatic repeat request indicator channel (PHICH) is described. The method for mapping a PHICH includes determining an index of a resource element group transmitting a repetitive pattern of the PHICH, according to a ratio of the number of available resource element groups in a symbol in which the PHICH is transmitted and the number of available resource element groups in a first or second OFDM symbol, and mapping the PHICH to the symbol according to the determined index. In transmitting the PHICH, since efficient mapping is performed considering available resource elements varying with OFDM symbols, repetition of the PHICH does not generate interference between neighbor cell IDs and performance is improved. | 11-05-2009 |
20090279419 | COMMUNICATION APPARATUS AND COMMUNICATION METHOD - To efficiently compress the information amount for feedback when a communication apparatus sends back a result of performing discrete cosine transform on the reception quality information to a communication apparatus of a communicating destination. In a communication apparatus for transmitting feedback information generated based on a plurality of reception quality information to a communicating destination apparatus, the feedback information is a result of performing discrete cosine transform on the plurality of reception quality information, and performing respective different quantization on signal components of at least a group of samples among signal components of a plurality of samples obtained by the discrete cosine transform. | 11-12-2009 |
20090303865 | OFDMA PREAMBLES SYSTEM AND METHOD - A preamble code usable in Orthogonal Frequency Division Multiple Access (OFDMA) for the physical layer (PHY), selected for improved PAPR in a 1024, 512 or 128 FFT OFDMA mode. Tables 2 to 7 detail code sequences having improved PAPR performance. The disclosed codes may be used in cellular wireless. | 12-10-2009 |
20090303866 | METHOD AND DEVICE FOR THE BASEBAND PROCESS OF THE SPACE-TIME/SPACE -FREQUENCY/SPATIAL DIVERSITY TRANSMITTER - A method and device for the baseband process of space-time/space-frequency/spatial diversity transmitter in the SC-FDMA system, the device is characterized in that: 1) an encoding means is connected to the output end of the M-point DFT module; 2) a space-time encoding means, for encoding the corresponding symbol of at least two adjacent symbol sets, and outputting at least two data sets; each sub-carrier mapping means maps respectively each data set to the corresponding antenna, so that the mapped data satisfy the requirements: The symbols mapped on each antenna keep the same sequence as the M symbols outputted by the M-point DFT module; the mapped symbols keep the same sub-carrier interval; the M data of each mapped SC-FDMA symbol are the M outputted data of the DFT module, or the inverse of the M outputted data, or the complex conjugate of the M outputted data, or the inverse complex conjugate of the M outputted data. The present invention implements effective space diversity, reduces PAPR, and makes frequency domain equalization feasible. | 12-10-2009 |
20090310477 | METHODS AND SYSTEMS FOR STICKY REGION ALLOCATION IN OFDMA COMMUNICATION SYSTEMS - Methods and apparatus for allocating a data region (termed “sticky region allocation”) in an orthogonal frequency-division multiplexing (OFDM) or orthogonal frequency division multiple access (OFDMA) frame so that a user terminal can receive/send data bursts for multiple OFDM/OFDMA frames, rather than inserting a MAP information element (MAP IE) for each user terminal in every frame, are provided. In this manner, the size of the control overhead, such as the downlink (DL) and uplink (UL) MAP messages, may be reduced. The reduced control overhead may increase the frame resources available for data traffic and thus, may boost the overall efficiency and performance of wireless systems using OFDM/OFDMA. | 12-17-2009 |
20090310478 | APPARATUS AND METHOD FOR ALLOCATING SUBCHANNELS AND CONTROLLING INTERFERENCE IN OFDMA SYSTEMS - An apparatus for allocating subchannels is provided. The apparatus includes: a subchannel allocation coefficient determination unit determining a subchannel allocation coefficient using a queue length of at least one terminal and a signal to interference plus noise ratio (SINR) of the at least one terminal and at least one relay station in an Orthogonal Frequency Division Multiple Access (OFDMA) system; and a subchannel allocation unit allocating a subchannel to at least one link formed in the OFDMA system using the subchannel allocation coefficient. | 12-17-2009 |
20090323509 | METHOD OF TRANSMITTING DATA SIGNALS IN A TELEPHONE NETWORK - A method of transmitting a data signal in a telephone network that is accessible via a vocoder and means for transmitting voice signals, the method comprising the steps of obtaining a modulated signal by subdividing the data signal into frames associated with mutually orthogonal states of a set of carriers (OFDM), processing the modulated signal in the vocoder, and delivering the processed signal to the voice signal transmission means. | 12-31-2009 |
20100002570 | Transmit diversity and spatial spreading for an OFDM-based multi-antenna communication system - A multi-antenna transmitting entity transmits data to a single- or multi-antenna receiving entity using (1) a steered mode to direct the data transmission toward the receiving entity or (2) a pseudo-random transmit steering (PRTS) mode to randomize the effective channels observed by the data transmission across the subbands. The PRTS mode may be used to achieve transmit diversity or spatial spreading. For transmit diversity, the transmitting entity uses different pseudo-random steering vectors across the subbands but the same steering vector across a packet for each subband. The receiving entity does not need to have knowledge of the pseudo-random steering vectors or perform any special processing. For spatial spreading, the transmitting entity uses different pseudo-random steering vectors across the subbands and different steering vectors across the packet for each subband. Only the transmitting and receiving entities know the steering vectors used for data transmission. | 01-07-2010 |
20100002571 | METHODS FOR TRANSCEIVING DATA IN MULTI-BAND ORTHOGONAL FREQUENCY DIVISION MULTIPLE ACCESS COMMUNICATIONS SYSTEM AND COMMUNICATIONS APPARATUSES UTILIZING THE SAME - A communications apparatus is provided. A receiving module receives a signal with a predetermined signal bandwidth. A low pass filter filters the signal to obtain a filtered signal. A filter bandwidth of the low pass filter is wide enough to pass the regular sub-carrier frequency components and at least half of the guard sub-carrier frequency components of the signal. An analog to digital converter samples the filtered signal with a sampling rate exceeding a standard sampling rate defined in accordance with the predetermined signal bandwidth of the signal to obtain a plurality of digital samples. A Fast Fourier Transform module performs a fast Fourier transform on a predetermined number of points of the digital samples to obtain a plurality of transformed samples. The predetermined number exceeds a standard number defined in accordance with the predetermined carrier bandwidth. A sub-carrier collector collects the data from the transformed samples. | 01-07-2010 |
20100008215 | EQUAL PHASE COMBINING TECHNIQUE FOR A ROBUST OFDM SYSTEM - A technique for an equal phase combining for a robust orthogonal frequency division multiplexing (OFDM) system under high delay spread channel is disclosed. In one embodiment, a method includes receiving and synchronizing transmitted OFDM symbols having cyclic prefixes via a symbol synchronizer module, removing the cyclic prefixes from the OFDM symbols, via a cyclic prefix remover module, to form time domain symbols, converting the time domain symbols to frequency domain symbols via an FFT module, equalizing a received sub-carrier with complex conjugate of estimated channel coefficients in frequency domain at the same sub-carrier frequency via an equalizer, combining the frequency domain symbols spread over multiple sub-carriers during transmission via a combiner, and detecting phase information from the mapped combined PSK constellation symbol via a detector module. | 01-14-2010 |
20100008216 | APPARATUS AND METHOD FOR ESTIMATING AND COMPENSATING TIME OFFSET AND/OR CARRIER FREQUENCY OFFSET IN MIMO SYSTEM BASED OFDM/OFDMA - The present invention relates to an apparatus and method for estimating and compensating for a time offset and a carrier frequency offset in a Multiple Input Multiple Output (MIMO) communication system that supports Orthogonal Frequency Division Multiplexing (OFDM) or Orthogonal Frequency Division Multiplexing Access (OFDMA). According to the present invention, a phase difference of pilot signals of the same transmitting antenna, which are received through receiving antennas, is calculated. An arc tangent operation is then carried out on the phase difference of the pilot signals to calculate a time offset linear phase and/or a carrier frequency offset linear phase. Further, a time offset compensation value and/or a carrier frequency offset compensation value are found by employing the time offset linear phase and/or the carrier frequency offset linear phase. A time offset and/or a carrier frequency offset with respect to pilots and data are compensated for by employing the time offset compensation value and/or the carrier frequency offset compensation value. | 01-14-2010 |
20100014413 | METHOD OF MULTI-ANTENNA WIRELESS DATA EMISSION, EMITTER AND RECEIVER USING THE METHOD - A method and device in the domain of wireless communication, and more specifically coding and decoding schemes useful in the context of MIMO (Multiple Input Multiple Output) or MISO (Multiple Input Single Output) communications especially used in conjunction of OFDM-like transmission schemes. A space frequency block code applies some well chosen two by two space frequency block codes to each pair of frequencies κ and κ+N/2. The proposed SFBC keep the constant envelope property for each antenna while leading to a good performance by introducing some spatial diversity. | 01-21-2010 |
20100020674 | Apparatus and method for synchronization acquisition and cell ID search in wireless communication system - A apparatus and method for allocating synchronization acquisition sequence in a time domain and allocating a cell ID search sequence in a frequency domain. In a method for transmitting a synchronization signal of a base station in a wireless communication system, a binary frequency-domain preamble sequence predetermined for cell ID search and a binary time-domain preamble sequence predetermined for synchronization acquisition are used to determine a complex time-domain preamble sequence except the binary time-domain preamble sequence among the time-domain preamble sequences that are generated according to an Inverse Fast Fourier Transform (IFFT) operation on the binary frequency-domain preamble sequence. The complex time-domain preamble sequence and the binary time-domain preamble sequence are transmitted to a mobile station. | 01-28-2010 |
20100027408 | LOW DENSITY LATTICE CODE GENERATOR MATRICES USING MUTUALLY ORTHOGONAL LATIN SQUARES - According to one general aspect, a method including receiving noisy data via a communications channel, wherein the noisy data includes a clean data component and a noise component. In various embodiments, the method may also include decoding, utilizing a low-density lattice code (LDLC) matrix, the received noisy data to substantially recover the clean data component. In some embodiments, the LDLC matrix may not include a matrix of less than a length of six cycles. In one embodiment, the LDLC matrix may be algebraically constructed. In various embodiments, the method may include storing the decoded clean data component. | 02-04-2010 |
20100039926 | Transmission Resource Assigning Method, Feedback Method And Processing Method For Response Signals - The present invention discloses a transmission resource assignment method for response signals, a feedback method of response signals and a processing method of response signals. The transmission resource assignment method for response signals according to the present invention includes the steps of: determining a list of mobile stations required to transmit response signals currently; determining the number of the response signals required to be transmitted by each mobile station; and assigning a frequency-domain sequence and a time-domain sequence for each mobile station to transmit the response signals; wherein for multiple mobile stations assigned with the same frequency-domain sequence, the time-domain sequence assigned to the mobile station required to transmit multiple response signal groups is divided into multiple subsequences to be used to transmit the multiple response signal groups of the mobile station respectively; and parts of the time-domain sequences of different mobile stations corresponding to the multiple subsequences are orthogonal to each other respectively. | 02-18-2010 |
20100046356 | METHOD FOR MULTIPLEXING CONTROL SIGNALS IN A MOBILE COMMUNICATION SYSTEM - Disclosed is a method for multiplexing control signals between a plurality of users when control signals for the plurality of users are allocated within one resource block. That is, a method for multiplexing control signals includes coding control signals for at least one user signals to correspond to a structure of a transmission block for the control signals among one or more dedicated resource block, multiplexing the control signals for the at least one user signals in the dedicated resource block, and transmitting the control signals, wherein the dedicated resource block is allocated for transmitting the control signals separately from data signals among a plurality of transmission resource blocks. A frequency division multiplexing (FDM) mode and a code division multiplexing (CDM) mode are used to multiplex the control signals for the plurality of users. | 02-25-2010 |
20100054115 | System and Method for Sidelobe Suppression in Communications Systems - A system and method for sidelobe suppression in OFDM communications systems is provided. A method for transmitting an information symbol having a plurality of information sub-carriers and a plurality of active interference cancellation (AIC) sub-carriers includes generating AIC sub-carrier data based on the information to be transmitted, populating the plurality of information sub-carriers with the information, populating the plurality of AIC sub-carriers with the AIC sub-carrier data, applying baseband processing to the information symbol, thereby producing a processed symbol, and transmitting the processed symbol. | 03-04-2010 |
20100061223 | SUBCARRIER ALLOCATION APPARATUS AND METHOD, SUBCARRIER DE-ALLOCATION APPARATUS AND METHOD IN OFDM SYSTEM - A subcarrier allocating apparatus allocating data to be transmitted to a plurality of orthogonal subcarriers in an orthogonal frequency division multiplexing (OFDM) system, the apparatus including: a logical index generator ( | 03-11-2010 |
20100067363 | METHOD AND SYSTEM FOR RADIO FREQUENCY (RF) GROUP DELAY COMPENSATION IN A BROADCAST SYSTEM - A radio device operable to compensate for a large RF filter group delay variation is provided. The radio device includes a receiving unit operable to receive an OFDM signal that comprises pilot subcarrier signals and data subcarrier signals. The radio device further includes a group delay (GD) compensator, operable in frequency domain, and configured to perform phase rotation to correct a group delay individually on tones of an OFDM symbol. The phase rotation is calculated as a function of the phase shifts of the received pilot subcarrier signals and subcarrier index. | 03-18-2010 |
20100067364 | METHOD AND SYSTEM FOR VARIANCE-BASED AUTOMATIC GAIN CONTROL IN OFDM SYSTEMS - Aspects of a method and system for variance-based automatic gain control in OFDM systems may include automatically controlling a gain for one or more received Orthogonal Frequency Division Multiplexing (OFDM) signals based on at least a signal variance derived from the received OFDM signals. The gain may be controlled via a variable gain amplifier, where the variable gain amplifier may be controlled via an analog and/or digital signal. The signal variance may be determined in an automatic gain control (AGC) circuit. The gain may be controlled via a feedback circuit. The signal variance may be generated via a difference between a mean-square signal and a mean-value-squared signal based on the received OFDM signals. The automatic gain control module may comprise a logarithm module, an integrator, and a dB-to-voltage mapper. The variance signal may be determined over a received slot of data. | 03-18-2010 |
20100067365 | TRANSMISSION SYSTEM, TRANSMISSION METHOD, TRANSMITTER, RECEIVER, DECODING METHOD, AND DECODER - A transmission system capable of obtaining an effect of orthogonality among time block codes and an effect of path diversity on a distorted channel is provided. In the transmission system including: a transmitter device transmitting an information signal S[n] multiplied by a code, the code being a time block code constituted by a plurality of time series symbols, the transmitter device multiplying the information signal by a plurality of the time block codes, respectively, multiplexing multiplication results on a time axis and transmitting multiplexed signals; and a receiver device including a reception filter, if an impulse response matrix of a channel is a matrix H, a characteristic of the reception filter is set to be represented by a complex conjugate transpose matrix H | 03-18-2010 |
20100080112 | Frequency Offset Estimation in Orthogonal Frequency Division Multiple Access Wireless Networks - A method of wireless transmission for estimating the carrier frequency offset in a base station of a received transmission from a user equipment (UE) accessing a radio access network. The method time de-multiplexes selected symbols of a received sub-frame, computes the frequency-domain symbols received from each antenna through an FFT, de-maps the UEs selected sub-carriers for each antenna, computes metrics associated to a carrier frequency offset hypothesis spanning a searched frequency offset window, repeats these steps on subsequent received sub-frames from the UE over an estimation interval duration, non-coherently accumulates the computed metrics and selects the carrier frequency offset hypothesis with largest accumulated metric amplitude. | 04-01-2010 |
20100085865 | METHOD AND AN APPARATUS FOR ESTIMATING A DELAY SPREAD OF A MULTIPATH CHANNEL - Low complex algorithms for estimating a delay spread or a RMS delay spread of a multipath channel using channel estimates are disclosed, leading to low overall power consumption. According to an embodiment of the present invention, a delay spread or a RMS delay spread of the multipath channel is determined based on a metric calculated as a function of channel estimates. In another embodiment, an average signal to noise ratio is taken into consideration in addition to the metric to estimate the delay spread or the RMS delay spread. In a further embodiment, the delay spread or the RMS delay spread of the multipath channel is estimated based on an average signal to noise ratio and on a metric being a function of the slope between subcarrier channel estimates. The present invention further relates to an apparatus for estimating a delay spread or a RMS delay spread of the multipath channel. | 04-08-2010 |
20100085866 | APPARATUS AND METHOD FOR ESTIMATING CHANNEL IN MIMO SYSTEM BASED OFDM/OFDMA - The present invention relates to an apparatus and method for estimating a channel in a MIMO wireless telecommunication system supporting the 0FDM/0FDMA. The present invention, in estimating a channel by using two or more pilots included in at least one received signal among received signals of a first channel and a second channel received through a first receiving antenna and received signals of a third channel and a fourth channel received through a second receiving antenna, determines a subchannel mapping rule respectively for the received signals of the first channel to the fourth channel, and estimates a channel with a different method according to the determined subchannel mapping rule. That is, the channel is estimated by using two or more pilots included in two or more tiles corresponding to the same subcarrier respectively, in case a subchannel rotation does not exist in the subchannel mapping rule, while the channel is estimated by using two pilots included in an individual tile, in case a subchannel rotation exists in the subchannel mapping rule. | 04-08-2010 |
20100091641 | TRANSMIT DIVERSITY SCHEME FOR UPLINK DATA TRANSMISSIONS - Systems and methods are described herein for transmitting uplink SC-FDMA symbols. When an extended cyclic prefix is used, the symbols are divided into pairs, and the first symbol and a function of the second symbol in each pair is transmitted via a first antenna and the second symbol and a function of the first symbol in each pair is transmitted via a second symbol. When an unpaired symbol remains, the unpaired symbol is divided into halves, and a first function of the halves is transmitted on the first antenna and a second function of the halves is transmitted on the second antenna. | 04-15-2010 |
20100103811 | METHOD FOR GENERATING MUTUALLY ORTHOGONAL SIGNALS HAVING A CONTROLLED SPECTRUM - A method for generating mutually orthogonal signals having a controlled spectrum, includes the generation of a plurality of mututally orthogonal, controlled-power discrete spectra s(i) having dimension Q, i designating spectrum number. The aforementioned spectra represent time signals in the spectral range and have a modulus &mgr; that is constant in a spectral line designation set G and zero everywhere else. The method includes the following steps: determining ( | 04-29-2010 |
20100110873 | METHOD OF TRANSMITTING SYNCHRONIZATION SIGNAL IN WIRELESS COMMUNICATION SYSTEM - A method of transmitting a synchronization signal includes generating a sequence P(k) for a synchronization signal from a Zadoff-Chu (ZC) sequence having the odd numbered length N, the sequence P(k) having the even numbered length N−I, mapping the sequence P(k) to subcarriers so that the sequence P(k) is halved with respect to a DC subcarrier, and transmitting the a synchronization signal in the subcarriers. Time/frequency ambiguity caused by a synchronization error can be avoided, and sequence detection errors can be decreased. | 05-06-2010 |
20100110874 | METHOD AND APPARATUS FOR TRANSMITTING SIGNAL IN A WIRELESS COMMUNICATION SYSTEM - A method and apparatus for transmitting a signal in a wireless communication system are disclosed. The signal transmission method includes grouping a plurality of subcarriers included in a first Orthogonal Frequency Division Multiple Access (OFDMA) symbol within distributed resources into a plurality of subcarrier groups, each subcarrier group having a predetermined number of subcarriers, distributing the plurality of subcarrier groups of the first OFDMA symbol according to a first permutation pattern, transmitting data in the distributed subcarrier groups of the first OFDMA symbol, grouping a plurality of subcarriers included in a second OFDMA symbol within the distributed resources into a plurality of subcarrier groups, each subcarrier group having a predetermined number of subcarriers, distributing the plurality of subcarrier groups of the second OFDMA symbol according to a second permutation pattern, and transmitting data in the distributed subcarrier groups of the second OFDMA symbol. | 05-06-2010 |
20100118691 | METHOD FOR GENERATING CODEWORD AND TRANSMITTING CONTROL INFORMATION USING THE SAME - A method for generating a codeword from a vector generated by combining four symbols PO, P1, P2 and P3 includes generating 16 vectors V | 05-13-2010 |
20100165828 | COMMUNICATIONS SYSTEM EMPLOYING CHAOTIC SPREADING CODES WITH STATIC OFFSETS - Methods for code-division multiplex communications. The method involve generating orthogonal or statistically orthogonal chaotic spreading codes (CSC | 07-01-2010 |
20100172235 | SYSTEM AND METHOD FOR INITIALIZATION OF A SCRAMBLING SEQUENCE FOR A DOWNLINK REFERENCE SIGNAL - A system and method for initialing a scrambling sequence for a downlink reference signal in a Long Term Evolution-Advanced (LTE-A) system. The system and method include initializing at the start of a radio frame, a scrambling sequence generator that initializes a seed of a scrambling sequence for downlink cell-specific reference signals for the LTE-A component carriers. The initialization seed is based on the component carrier ID. The system and method can transmit the reference signal in filler bands located between at least two component carriers in the LTE-A system. | 07-08-2010 |
20100182897 | SIGNAL DETECTING METHOD FOR SPATIAL MULTIPLEXING MULTIPLE-INPUT MULTIPLE-OUTPUT SYSTEMS - A method for detecting signals in spatial multiplexing multiple-input multiple-output (MIMO) systems using a QR-decomposition with M (QRD-M) algorithm is provided. The method includes receiving signals, limiting upper and lower bounds of a complexity in a QR-decomposition with M (QRD-M) algorithm, and detecting the received signals using the QRD-M algorithm. The signal detecting method can effectively reduce the amount of operation generated while detecting signals, using the QRD-M algorithm where the upper and lower bounds of the complexity are limited. | 07-22-2010 |
20100182898 | Apparatus and method for transmitting and receiving uplink sounding signal in broadband wireless communication system - A terminal is capable of transmitting an orthogonal sequence in a broadband wireless communication system. Operations of a transmitting end include generating a sequence corresponding to sequence allocation information of the transmitting end among a plurality of candidate sequences; generating a signal string corresponding to the sequence; and transmitting the signal string over a channel defined for transmission of the signal string. | 07-22-2010 |
20100195482 | HIERARCHICALLY MODULATED OFDM COMMUNICATION FROM A SATELLITE-BASED TRANSMITTER WITH REDUCED SECONDARY DATA LOSS FROM CLIPPING - High priority data and low priority digital data are transmitted as primary and secondary data in hierarchically modulated, orthogonal frequency division multiplexing (OFDM) from an earth-orbiting satellite. To enable the transmitter amplifier to be operated with less back-off from saturation without clipping, the low priority OFDM symbols have fewer samples than the high priority OFDM symbols, and the high priority samples on which the low priority samples are superimposed are selected according to a first deterministic rule using sample power comparisons of the high priority samples to concentrate the low priority samples on those high priority samples having lower (optimally, the lowest) sample power. The low priority samples are distributed on the selected high priority samples according to a second deterministic rule relating the original low priority sample order to the original high priority sample order. | 08-05-2010 |
20100195483 | SIGNALING METHOD IN AN OFDM MULTIPLE ACCESS SYSTEM - A method for reducing the peak-to-average ratio in an OFDM communication signal is provided. The method includes defining a constellation having a plurality of symbols, defining a symbol duration for the OFDM communication signal, and defining a plurality of time instants in the symbol duration. A plurality of tones are allocated to a particular communication device, and a discrete signal is constructed in the time domain by mapping symbols from the constellation to the time instants. A continuous signal is generated by applying an interpolation function to the discrete signal such that the continuous signal only includes sinusoids having frequencies which are equal to the allocated tones. | 08-05-2010 |
20100195484 | SIGNALING METHOD IN AN OFDM MULTIPLE ACCESS SYSTEM - A method for reducing the peak-to-average ratio in an OFDM communication signal is provided. The method includes defining a constellation having a plurality of symbols, defining a symbol duration for the OFDM communication signal, and defining a plurality of time instants in the symbol duration. A plurality of tones are allocated to a particular communication device, and a discrete signal is constructed in the time domain by mapping symbols from the constellation to the time instants. A continuous signal is generated by applying an interpolation function to the discrete signal such that the continuous signal only includes sinusoids having frequencies which are equal to the allocated tones. | 08-05-2010 |
20100238787 | DETECTION OF TIME-FREQUENCY HOPPING PATTERNS - The present invention relates to a method for detecting a pilot pattern, comprising a pilot signal s | 09-23-2010 |
20100246376 | CELL-SPECIFIC SHIFTING OF REFERENCE SIGNALS IN MULTI-STREAM TRANSMISSIONS - A base station is provided. The base station comprises a downlink transmit path comprising circuitry configured to transmit a plurality of reference signals in one or more subframes. Each subframe comprises one or more resource blocks. Each resource block comprises S Orthogonal Frequency Division Multiplexing (OFDM) symbols. Each of the S OFDM symbols comprises N subcarriers, and each subcarrier of each OFDM symbol comprises a resource element. The base station further comprises a reference signal allocator configured to allocate the plurality of reference signals to selected resource elements of a resource block, and circularly shift the plurality of reference signals in a time domain of the resource block by an h | 09-30-2010 |
20100271930 | SCATTERED PILOT PATTERN AND CHANNEL ESTIMATION METHOD FOR MIMO-OFDM SYSTEMS - Methods and apparatus are provided for inserting data symbols and pilot symbols in an OFDM (orthogonal frequency division multiplexing) transmission resource utilizing frequency hopping patterns for the data symbols and/or the pilot symbols. Data symbols and pilot symbols are allocated for down link (base station to mobile station) and up link (mobile station to bases station) transmission resources in a two-dimensional time-frequency pattern. For each antenna of a MIMO-OFDM (multiple input multiple output OFDM) communication system, pilot symbols are inserted in a scattered pattern in time-frequency and data symbols are inserted in an identical frequency-hopping pattern in time-frequency as that of other antennas. | 10-28-2010 |
20100284265 | SEQUENCE NUMBER ESTABLISHING METHOD, WIRELESS COMMUNICATION TERMINAL APPARATUS AND WIRELESS COMMUNICATION BASE STATION APPARATUS - A wireless communication terminal apparatus wherein the occurrences of inter-sequence interferences between cells can be reduced. In this apparatus, a sequence number deciding part ( | 11-11-2010 |
20100329107 | METHOD OF ALLOCATING UPLINK RESOURCE REGION - A method for a base station to allocate an uplink resource using an uplink map in a wireless access system is disclosed. The present invention includes the steps of receiving a system information delivery message including subframe configuration information, receiving a map message including information on an allocation location of an uplink resource region, and calculating a time of allocating the uplink resource region using the subframe configuration information and the information on the allocation location of the uplink resource region. | 12-30-2010 |
20110007625 | DEMODULATOR AND FRAME SYNCHRONIZATION METHOD - A clock-frequency-deviation detecting unit detects a clock-frequency deviation based on a synchronization signal for taking a frame synchronization included in a reception signal. A clock-frequency-deviation compensating unit compensates a clock-frequency deviation of the reception signal in a former stage of an FFT unit. A timing control unit controls a frame pulse position indicating a head of a frame, based on the synchronization signal. The FFT unit performs an FFT on the reception signal with the frame pulse position as a frame head position, and a demodulating unit demodulates an output of the FFT unit. | 01-13-2011 |
20110007626 | ORTHOGONAL CODE DIVISION MULTIPLEX CCK (OCDM-CCK) METHOD AND APPARATUS FOR HIGH DATA RATE WIRELESS LAN - Orthogonal Code Division Multiplexing (OCDM) transceiver system with Complementary Code Keying (CCK) and method for baseband OCDM-CCK encoding and decoding are provided. The OCDM-CCK method comprises a serial-to-parallel data converter converting a stream of M*n-bit serial data to n-bit parallel data in ‘M’ parallel baseband paths, and encoding each n-bit data segment with a distinct complementary code using CCK modulation for spreading. The CCK encoded baseband signals are all summed and transmitted simultaneously on the same carrier frequency and spread spectral bandwidth. The OCDM-CCK method of encoding and transmission of information, results in enhanced datarates of 33 Mbps, 88 Mbps, 176 Mbps and higher multiples of 5.5 Mbps with backward compatibility for IEEE 802.11b WLAN (Wireless Local Area Network), and wireless communication networks supporting real time Direct Sequence Spread Spectrum (DSSS). | 01-13-2011 |
20110013505 | HIGH DIMENSION SIGNALING USING ORTHOGONAL WAVEFORM DIVISION MULTIPLEX - A communications system ( | 01-20-2011 |
20110013506 | BASE STATION APPARATUS AND COMMUNICATION CONTROL METHOD - A base station apparatus capable of communicating with a user equipment terminal using a downlink shared channel is disclosed. The base station apparatus includes a user selection unit selecting a user equipment terminal to which radio resources are to be allocated, the selection being based on whether there is a MAC-layer control signal to be transmitted to the user equipment terminal. | 01-20-2011 |
20110044159 | BASE STATION APPARATUS, MOBILE STATION APPARATUS AND SYNCHRONIZATION CHANNEL TRANSMISSION METHOD - A base station apparatus is disclosed for use in a mobile communication system including multiple cells having multiple sectors. The base station apparatus includes a synchronization channel generation unit configured to generate a synchronization channel for use in cell search by a user apparatus and a transmitting unit configured to wirelessly transmit a signal including the synchronization channel. The synchronization channel includes a primary synchronization channel and a secondary synchronization channel. The primary synchronization channel includes multiple types of sequences, and the secondary synchronization channel transmitted in a sector of a cell includes a code derived from a predefined generation polynomial equation corresponding to the primary synchronization channel. | 02-24-2011 |
20110058470 | RANGING APPARATUS AND METHOD FOR IMPROVING RANGING PERFORMANCE IN OFDMA SYSTEM - Disclosed herein is a ranging apparatus and method. The ranging apparatus includes a correlation unit for correlating OFDMA reception signals with inverse fast Fourier transformed ranging codes, and outputting correlation result values. A threshold determination unit determines a threshold value depending on characteristics of the reception signals. A comparison unit estimates a delay time by selecting a maximum value from among the correlation result values, and detects a ranging code by comparing the maximum value with the threshold value, and then outputs and feeds back the ranging code and the delay time when the maximum value is equal to or greater than the threshold value. A weight multiplication unit delays the ranging code by the delay time, multiplies a weight by the delayed ranging code, and outputs a resulting value. A calculation unit subtracts the resulting value from the reception signals, and provides adjusted reception signals. | 03-10-2011 |
20110116359 | METHODS AND APPARATUS FOR INTERLEAVING IN OFDM/OFDMA SYSTEMS - An interleaver of an OFDM/OFDMA transceiver reshapes a binary vector to be transmitted into a matrix, rotates bits in respective columns of the matrix, divides respective rows of the matrix into an integer number of interleaving blocks, and interleaves the bits in the respective interleaving blocks. | 05-19-2011 |
20110128842 | Method for Estimating a Received Signal and Corresponding Device - A method and apparatus for estimating a transmission channel in a receiver of an OFDMA signal formed by a plurality of carriers modulated by data elements and distributed in the time-frequency domain in successive symbols, the plurality of carriers including pilot carriers, modulated by reference data elements known by receivers. The method includes: receiving a signal comprising a series of n symbols covering at least one resource block; making an initial channel estimation by identifying the pilot carriers included in the series of n symbols; determining diagonal entries of p frequency domain channel matrices G | 06-02-2011 |
20110134747 | Method for Uplink Transmitting Control Information - A method for uplink transmitting control information from a user equipment in a wireless communication system comprises selecting a specific point among a plurality of points distributed into a symbol space, corresponding to control information, the symbol space including a modulation dimension and a sequence dimension; mapping a signal corresponding to the specific point with a control channel including single carrier-frequency division multiple access (SC-FDMA) symbols; and transmitting the control channel. Preferably, the specific point belongs to the sequence dimension. | 06-09-2011 |
20110176406 | Efficient Zadoff-Chu Sequence Generation - The present invention generates exponents of elements of a Zadoff-Chu sequence representing a preamble for uplink synchronization of mobile stations or a mobile station reference signal by first obtaining (S | 07-21-2011 |
20110199888 | SIGNAL SEPARATION DEVICE AND SIGNAL SEPARATING METHOD - A signal separation device includes a column switching unit switching a column vector of a channel matrix obtained by estimating a propagation path characteristic so that a transmitted signal component of each transmit antenna is in a left end, a QR decomposition layering unit multiplying received signals by an output from the column switching unit, and outputting a received signal vector in which the received signal is layered so that a transmitted signal exists in a first row, an interference cancellation unit cancelling an interference component from a signal in the first row by using a signal other than the signal in the first row, a signal candidate point selecting unit selecting a prescribed number of signal candidate points from among signals output by the interference cancellation unit, and a signal separation unit separating the transmitted signal from the layered received signal vector using the selected signal candidate point. | 08-18-2011 |
20110222393 | METHOD OF TRANSMITTING CONTROL SIGNALS IN WIRELESS COMMUNICATION SYSTEM - A method of transmitting control signals in a wireless communication system includes multiplexing a first control signal with a second control signal in a slot, the slot comprising a plurality of orthogonal frequency division multiplexing (OFDM) symbols in time domain, the plurality of OFDM symbols being divided into a plurality of data OFDM symbols and a plurality of reference signal (RS) OFDM symbols, wherein the first control signal is mapped to the plurality of data OFDM symbols after the first control signal is spread by a base sequence in the frequency domain, the RS is mapped to the plurality of RS OFDM symbols, the second control signal is mapped to at least one of the plurality of RS OFDM symbols, and transmitting the first control signal and the second control signal in the slot. | 09-15-2011 |
20110249549 | METHOD AND DEVICE FOR SEQUENCING THE ZC SEQUENCES OF THE RACH - A method and device for sequencing the ZC sequences of the RACH is provided, wherein, the method for sequencing the ZC sequences comprises: according to the CM of OPSK, ZC sequences of the RACH are divided into low CM group and high CM group, to make the index of each ZC sequence within the low CM group smaller or larger than the index of each ZC sequence within the high CM group; according to the maximum cell radius or maximum cyclic shift supported by the ZC sequences under a high speed circumstance, the ZC sequences within the low CM group and within the high CM group are respectively divided into S sub-groups using S−1 maximum cyclic shift thresholds; according to the CMs of the ZC sequences, the sequences are sequenced within each sub-group, to make the ZC sequences in adjacent sub-groups within the low CM group and within the high CM group have different sequencing and the ZC sequences in adjacent sub-groups between the low CM group and the high CM group have the same sequencing. | 10-13-2011 |
20110255395 | METHOD FOR CONSTRUCTING SPACE-TIME/SPACE-FREQUENCY CODE, AND TRANSMITTING METHOD AND APPARATUS - A method for constructing a space-time/space-frequency code, and a transmitting method and apparatus are provided, which relate to the field of wireless communication technologies. The method for constructing a space-time/space-frequency code includes: classifying at least two transmitter antennas into K groups, and classifying information symbols into K′ groups; constructing a Toeplitz matrix for information symbols in each group according to the number of transmitter antennas in a transmitter antenna group; and substituting the Toeplitz matrix for nonzero elements in an Orthogonal Space-Time Block Coding (OSTBC) matrix that is based on K and K′, and when the OSTBC matrix comprises a zero element, substituting a zero matrix with a corresponding dimension, for the zero element. The space-time code constructed with the above method has orthogonality. | 10-20-2011 |
20110273977 | SYSTEM AND METHOD FOR CHANNEL STATE RELATED FEEDBACK IN MULTI-USER MULTIPLE-INPUT-MULTIPLE-OUTPUT SYSTEMS - System and method for dimension reduction and for channel and interference condition feedback in a Multi-User Multiple-Input-Multiple-Output (MU MIMO) wireless communication systems. The method for dimension reduction includes determining a number of virtual antennas, v | 11-10-2011 |
20110299380 | PILOT SIGNAL IN AN FDMA COMMUNICATION SYSTEM | 12-08-2011 |
20110305133 | OFDM TRANSMISSION METHOD, WHICH IS INTENDED BOTH FOR SPORADIC AND FOR CONTINUOUS DATA COMMUNICATION, FOR A WLAN - In an OFDM-based transmission method it can be stated for the preamble (4, 7) of a data packet that its N preamble segments (B, | 12-15-2011 |
20120026861 | DECODING DEVICE, DECODING METHOD, AND PROGRAM - A decoding device includes an acquisition unit configured to acquire a first frequency signal including a narrowband signal and a wideband signal, a direct inverse orthogonal transform unit configured to perform a direct matrix operation with respect to the narrowband signal of the first frequency signal so as to perform inverse orthogonal transform, and a high-speed inverse orthogonal transform unit configured to perform inverse orthogonal transform employing a high-speed operation method with respect to the wideband signal of the first frequency signal. | 02-02-2012 |
20120039160 | INTEGRATED CIRCUIT FOR RESPONSE SIGNAL SPREADING - A wireless communication apparatus capable of minimizing the degradation of the separation characteristic of response signals to be code-multiplexed. In the apparatus, a control part ( | 02-16-2012 |
20120044796 | METHOD FOR GENERATING SIGNAL PATTERN USING MODULUS OR SEQUENCE, AND DEVICE THEREOF - Disclosed are a method and an apparatus for generating signal patterns used for a transmission/reception process between a terminal and a base station by using a modular sonar sequence. | 02-23-2012 |
20120063292 | BASE STATION APPARATUS AND RADIO COMMUNICATION METHOD - A wireless communication apparatus capable of minimizing the degradation in separation characteristic of a code multiplexed response signal. In this apparatus, a control part ( | 03-15-2012 |
20120087230 | Method For Antenna Calibration In A Wideband Communication System - The present invention relates to a method for antenna calibration in a communication system having a bandwidth divided into multiple frequency intervals M with multiple communication units | 04-12-2012 |
20120120787 | RECTANGULAR POWER SPECTRAL DENSITIES OF ORTHOGONAL FUNCTIONS - In this application, a set of orthogonal functions is introduced whose power spectral densities are all rectangular shape. To find the orthogonal function set, it was considered that their spectrums (Fourier transforms of the functions) are either real-valued or imaginary-valued, which are corresponding to even and odd real-valued time domain signals, respectively. The time domain functions are all considered real-valued because they are actually physical signals. The shape of the power spectral densities of the signals are rectangular thus, the Haar orthogonal function set can be employed in the frequency domain to decompose them to several orthogonal functions. Based on the inverse Fourier transform of the Haar orthogonal functions, the time domain functions with rectangular power spectral densities can be determined. This is equivalent to finding the time-domain functions by taking the inverse Fourier transform of the frequency domain Walsh functions. The obtained functions are sampled and truncated to generate finite-length discrete signals. Truncation destroys the orthogonality of the signals. The Singular Value Decomposition method is used to restore the orthogonality of the truncated discrete signals. | 05-17-2012 |
20120140613 | MULTIPLE TRANSMIT ANTENNA INTERLEAVER DESIGN - An arrangement of interleavers allocates bits from an input symbol across sub-symbols transmitted via sub-carriers of multiple orthogonal frequency division multiplex (OFDM) carriers. The input bits are allocated in a fashion to provide separation across subcarriers, and rotation of sub-symbols across the OFDM carriers provides additional robustness in the present of signal path impairments. | 06-07-2012 |
20120140614 | OFDM APPARATUS USING THREE-DIMENSIONAL HEXADECIMAL SIGNAL CONSTELLATION - A three-dimensional OFDN apparatus of the present invenstion comprises: a serial-parallel conversion unit for converting a serial input signal into N parallel input signals; a three-dimensional signal mapping unit for mapping the N parellel input signals on three-dimensional coordinates of a cube-in-cube type constellation, respectively; and a two-dimensional inverse Fourier transform unit for performing an inverse Fourier transform by generating a two-dimensional matrix on the basis of the mapped three-dimensional coordinates. | 06-07-2012 |
20120147730 | WIRELESS COMMUNICATIONS SYSTEM WITH SECONDARY SYNCHRONIZATION CODE BASED ON VALUES IN PRIMARY SYNCHRONIZATION CODE - A wireless communication system. The system comprises transmitter circuitry (BST | 06-14-2012 |
20120170443 | ULTRA-WIDE BANDWIDTH SYSTEM AND METHOD FOR IN-PREMISES WIRELESS NETWORKING - An IS-OFDM system for ultra-wideband (UWB) wireless communications that suppresses narrow-band interference, comprising an in-premises base station (IBS) is described. The IBS further comprises an IS-OFDM transceiver for communicating with a plurality of in-premises terminals (ITs) without creating interference outside an in-premises perimeter. Further, a method for operating an IS-OFDM system for ultra-wideband (UWB) wireless communications that suppresses narrow-band interference and provides local area networking services, in-premises distribution of broadcast cable channels and in-premises wireless access and routing to external networks is described, without creating interference outside an in-premises perimeter. | 07-05-2012 |
20120207010 | WIRELESS COMMUNICATION SYSTEM, TRANSMITTER, RECEIVER AND WIRELESS COMMUNICATION METHOD - A transmitter transmits a wireless signal produced by allocating data to component carriers for a plurality of communication bands, and a receiver receives the wireless signal and carries out a reception process for the received wireless signal with a predetermined reception sampling frequency are provided, and the component carriers are arranged at such positions that the data do not overlap with each other when the component carriers are superimposed on a frequency axis. | 08-16-2012 |
20120327757 | DETECTION METHOD AND APPARATUS FOR MULTIPLE-INPUT MULTIPLE-OUTPUT SINGLE-CARRIER BLOCK TRANSMISSION SYSTEM - The present invention discloses a detection method, a receiver, and an apparatus in a multiple-input multiple-output single-carrier block transmission system. Through sorted QR decomposition (Sorted QR Decomposition, SQRD) decomposition based on a minimum mean squared error (Minimum Mean Squared Error, MMSE) criterion, an matrix inverse operation in minimum mean squared error equalization is avoided, and complexity is significantly reduced. In addition, through layer-by-layer soft interference cancellation detection after the SQRD decomposition and further iterative processing, better detection performance may be obtained. Especially, inter-stream interference suppression may be performed in first iteration. Compared with a conventional parallel iterative soft interference cancellation detection algorithm, with the same number of times of iteration, especially under the limit that a receiver can only support a small number of limes of iteration, the inter-stream interference suppression has more evident advantages, and an advantage in the aspect of cost performance is very obvious. | 12-27-2012 |
20130010586 | METHOD AND APPARATUS FOR RESOURCE MAPPING AND CODE DIVISION MULTIPLEXING - The present disclosure discloses a method and an apparatus for resource mapping and code division multiplexing. In the present disclosure, each cell selects a mapping scheme among at least two mapping schemes to implement resource mapping, which effectively reduces interference imposed on reference signal symbols of users at the edge of a cell; vector switching is performed for an orthogonal matrix to obtain multiple different codeword sequences and implement codeword design. | 01-10-2013 |
20130039163 | ORTHOGONAL RESOURCE SELECTION TRANSMIT DIVERSITY AND RESOURCE ASSIGNMENT - Methods of allocating orthogonal resources of a wireless communication network to a user equipment (UE) that uses transmit diversity are disclosed. In one or more embodiments, the UE is configured to transmit a reference symbol and a modulated symbol on multiple orthogonal resources on an antenna. The method includes: selecting, by the UE, a first and a second orthogonal resource, respectively, from a plurality of orthogonal resources according to the state of information bits to be communicated by the UE; and transmitting, by the UE, the reference and data symbols on the first and the second orthogonal resource, respectively, on one antenna. The first and the second resource are different for at least one of the states of the information bits. The first and the second resource are both in the same physical resource block. | 02-14-2013 |
20130077464 | ORTHOGONAL VARIABLE SPREADING FACTOR CODE SEQUENCE GENERATION - An apparatus generally having a first circuit and a second circuit is disclosed. The first circuit may be configured to generate (i) a plurality of first code bits in response to an index value and (ii) a plurality of first intermediate bits in response to the index value. The first code bits may be generated in parallel with the first intermediate bits. The second circuit may be configured to generate a plurality of second code bits in response to all of (i) the index value, (ii) the first code bits and (iii) the first intermediate bits. A combination of the first code bits and the second code bits generally forms one of a plurality of orthogonal codes. | 03-28-2013 |
20130077465 | COMMUNICATION APPARATUS AND RESOURCE DERIVATION METHOD - This invention is applied to a communication apparatus that uses one or more code words to transmit or receive appropriate information on a PUSCH. Assuming that the i-th code word CW_i is used alone to transmit the appropriate information, the communication apparatus of the invention uses a Formula (1) to calculate the number of resources Q′_i. When one or more code words are used to transmit the appropriate information, the communication apparatus uses a Formula (2) to calculate the number of resources Q′. | 03-28-2013 |
20130088949 | METHODS AND SYSTEMS FOR CSI-RS RESOURCE ALLOCATION IN LTE-ADVANCE SYSTEMS - A method of allocating resource elements in an orthogonal frequency division multiplexed (OFDM) system for transmission of a channel state information reference signal (CSI-RS) is disclosed. The method includes converting one or more resource elements to a two-dimensional frequency-time domain; and partitioning the one or more converted resource elements to units of a physical resource block (PRB). One or more resource elements are patterned over at least a portion of the PRB for transmission of the CSI-RS. According to an embodiment, the CSI-RS resource elements with a same subcarrier index for a common cell are code division multiplexed (CDM), with a CDM dimension equal to a number of CSI-RS resource elements with the same subcarrier index for the common cell. | 04-11-2013 |
20130094344 | CDD PRECODING FOR OPEN LOOP SU MIMO - A method for data transmission, comprises the steps of modulating data to be transmitted via a transmitter into a plurality of modulated symbols, generating a codebook comprising a plurality of codewords, selecting a codeword from the codebook as a precoding matrix by a predetermined cycling selection, precoding the modulated symbols with the precoding matrix selected, and transmitting the precoded modulated symbols. | 04-18-2013 |
20130114392 | METHOD AND APPARATUS FOR RESOURCE MAPPING AND CODE DIVISION MULTIPLEXING - The present disclosure discloses a method and an apparatus for resource mapping and code division multiplexing. In the present disclosure, each cell selects a mapping scheme among at least two mapping schemes to implement resource mapping, which effectively reduces interference imposed on reference signal symbols of users at the edge of a cell; vector switching is performed for an orthogonal matrix to obtain multiple different codeword sequences and implement codeword design, so that a problem that the output power of reference signal symbols is unbalanced can be effectively alleviated. | 05-09-2013 |
20130121130 | CARRIER AGGREGATION IN WIRELESS COMMUNICATION SYSTEMS - Provided is a data transmission system using a carrier aggregation. The data transmission system may assign a radio resource based on a correspondence relationship between a downlink and an uplink, and may transmit data using the assigned radio resource. | 05-16-2013 |
20130170333 | METHOD AND APPARATUS FOR TRANSMITTING AND RECEIVING A PILOT SEQUENCE IN A BROADCASTING COMMUNICATION SYSTEM - A method and an apparatus for transmitting and receiving a pilot sequence in an Single Carrier-Orthogonal Frequency Division Multiplexing (SC-OFDM) scheme of a broadcasting communication system. The method includes determining seed values for Orthogonal Frequency Division Multiplexing (OFDM) symbols; generating pilot sequences including information related to an OFDM symbol index by applying a Zadoff-Chu sequence to each of the seed values; inserting the pilot sequences into a determined subcarrier position in a frame according to a pilot pattern; and transmitting the frame. | 07-04-2013 |
20130235714 | METHOD AND APPARATUS FOR A 1 MHZ LONG TRAINING FIELD DESIGN - An approach is provided for defining a 1 MHz preamble of a packet. The approach involves determining a preamble sequence of a packet, the preamble sequence having a determinable length. The approach also involves causing, at least in part, the preamble sequence to be divided into a predetermined number of blocks. The approach further involves causing, at least in part, a mathematical operation and a summation over the predetermined number of blocks and a corresponding number of received blocks. The approach also involves causing, at least in part, the summation to be maximized to determine the preamble sequence corresponds to one of a first bandwidth or a second bandwidth, the second bandwidth being greater than the first bandwidth, to determine a type of the packet. | 09-12-2013 |
20130286812 | METHOD OF TRANSMITTING REFERENCE SIGNAL AND TRANSMITTER USING THE SAME - A method and apparatus of transmitting a reference signal in a wireless communication system is provided. A reference signal sequence is generated by using a pseudo-random sequence. A portion or entirety of the reference signal sequence is mapped to at least one resource block and is transmitted. The pseudo-random sequence is generated by a gold sequence generator which is initialized with initial values obtained by using cell identifier. The reference signal provides low PAPR and high cross correlation characteristic. | 10-31-2013 |
20130294217 | RADIO TRANSMITTER, RADIO COMMUNICATION SYSTEM, AND RADIO TRANSMISSION METHOD - A transmission apparatus comprising a plurality of antennas, a scheduler configured to perform transmission scheduling in units of chunks each determined based on a prescribed frequency bad and a prescribed time so as to transmit signals via the plurality of antennas, and a transmission circuit configured to apply phase rotations to signals, where a phase rotation difference between adjacent subcarriers in an antenna generated from the phase rotations is set to either a first value smaller than (n−1)/(Fc×Ts) or a second value larger than (n−1)/(Fc×Ts) where Fc denotes the frequency band width of the chunk, Ts denotes a length of time for an Orthogonal Frequency Division Multiplexing (OFDM) symbol and n denotes a number based on an antenna index of the antenna in which the phase rotation was applied to the signals. | 11-07-2013 |
20130301400 | System Access and Synchronization Methods for MIMO OFDM Communications Systems and Physical Layer Packet and Preamble Design - A method and apparatus are provided for performing acquisition, synchronization and cell selection within an MIMO-OFDM communication system. A coarse synchronization is performed to determine a searching window. A fine synchronization is then performed by measuring correlations between subsets of signal samples, whose first signal sample lies within the searching window, and known values. The correlations are performed in the frequency domain of the received signal. In a multiple-output OFDM system, each antenna of the OFDM transmitter has a unique known value. The known value is transmitted as pairs of consecutive pilot symbols, each pair of pilot symbols being transmitted at the same subset of sub-carrier frequencies within the OFDM frame. | 11-14-2013 |
20130322229 | APPARATUS AND METHOD FOR TRANSMITTING AND RECEIVING OF CYCLIC SHIFT PARAMETER FOR SUPPORTING ORTHOGONALITY IN MIMO ENVIRONMENT - A method includes: determining a Cyclic Shift (CS) parameter that implicitly indicates an orthogonality allocation rule and orthogonality-related information, by determining a multiple access state of a User Equipment (UE), and transmitting the determined CS parameter to the UE, wherein the orthogonality-related information includes an Orthogonal Cover Code indicated by the CS parameter, the orthogonality allocation rule is determined as a uniform scheme or a non-uniform scheme according to the CS parameter, determining the CS parameter by which the non-uniform scheme is applied if the UE is in a Single User Multiple Input Multiple Output state, and determining the CS parameter by which the uniform scheme is applied if the UE is in a Multiple User Multiple Input Multiple Output state. | 12-05-2013 |
20130329542 | ULTRA-WIDE BANDWIDTH SYSTEM AND METHOD FOR IN-PREMISES WIRELESS NETWORKING - An IS-OFDM system for ultra-wideband (UWB) wireless communications that suppresses narrow-band interference, comprising an in-premises base station (IBS) is described. The IBS further comprises an IS-OFDM transceiver for communicating with a plurality of in-premises terminals (ITs) without creating interference outside an in-premises perimeter. Further, a method for operating an IS-OFDM system for ultra-wideband (UWB) wireless communications that suppresses narrow-band interference and provides local area networking services, in-premises distribution of broadcast cable channels and in-premises wireless access and routing to external networks is described, without creating interference outside an in-premises perimeter. | 12-12-2013 |
20140043955 | CARRIER AGGREGATION IN WIRELESS COMMUNICATION SYSTEMS - Provided is a data transmission system using a carrier aggregation. The data transmission system may assign a radio resource based on a correspondence relationship between a downlink and an uplink, and may transmit data using the assigned radio resource. | 02-13-2014 |
20140050076 | METHOD FOR GENERATING A SUPERSET OF QUASI-ORTHOGONAL SETS OF SEQUENCES - Generate a first set S comprising a plurality of quasi-orthogonal sets of sequences; generate L number of second sets of quasi-orthogonal sets of sequences T | 02-20-2014 |
20140140188 | Cooperative Subspace Multiplexing in Communication Networks - A source node selects a plurality of transmitting nodes to cooperatively encode a set of original packets to transfer to a destination node. Encoding produces a plurality of coded packets and a corresponding code matrix of coefficients. The coded packets and the corresponding code matrix comprise a set of independent equations of independent variables in a system of linear equations, wherein the independent variables comprise the original packets. A destination node may select a set of receiving nodes to cooperatively receive the transmissions. The destination node collects the coded packets and code matrix from the receiving nodes, which provide a sufficient number of independent equations for decoding the original packets. Decoding comprises calculating a solution for the system of linear equations. | 05-22-2014 |
20140140189 | Cooperative Subspace Demultiplexing in Communication Networks - A source node selects a plurality of transmitting nodes to cooperatively encode a set of original packets to transfer to a destination node. Encoding produces a plurality of coded packets and a corresponding code matrix of coefficients. The coded packets and the corresponding code matrix comprise a set of independent equations of independent variables in a system of linear equations, wherein the independent variables comprise the original packets. A destination node may select a set of receiving nodes to cooperatively receive the transmissions. The destination node collects the coded packets and code matrix from the receiving nodes, which provide a sufficient number of independent equations for decoding the original packets. Decoding comprises calculating a solution for the system of linear equations. | 05-22-2014 |
20140140190 | Wireless Terminal Apparatus and Wireless Base Station Apparatus - Both a wireless terminal apparatus and wireless base station apparatus are provided that can, in an operation of encoding the control signals of the upstream link transmitted from the multiple terminal stations while encoding with regard to each of the terminal stations, increase a number of the terminal stations to which different codes are respectively assigned. A wireless terminal apparatus includes: an encoding information receiving portion receiving encoding information which is used at the wireless terminal apparatus from the base station; a phase-shifting unit which conducts a phase-shifting operation on a predetermined first code based on the encoding information; a code selection unit which, based on the received encoding information, selects a second code from multiple codes orthogonally crossing each other; and a control signal encoding portion which conducts an encoding operation on the control signal that is going to be transmitted to the base station by using both the first code on which the phase-shifting operation has been conducted and the second code. | 05-22-2014 |
20140140191 | Wireless Terminal Apparatus and Wireless Base Station Apparatus - Both a wireless terminal apparatus and wireless base station apparatus are provided that can, in an operation of encoding the control signals of the upstream link transmitted from the multiple terminal stations while encoding with regard to each of the terminal stations, increase a number of the terminal stations to which different codes are respectively assigned. A wireless terminal apparatus includes: an encoding information receiving portion receiving encoding information which is used at the wireless terminal apparatus from the base station; a phase-shifting unit which conducts a phase-shifting operation on a predetermined first code based on the encoding information; a code selection unit which, based on the received encoding information, selects a second code from multiple codes orthogonally crossing each other; and a control signal encoding portion which conducts an encoding operation on the control signal that is going to be transmitted to the base station by using both the first code on which the phase-shifting operation has been conducted and the second code. | 05-22-2014 |
20140140192 | Wireless Terminal Apparatus and Wireless Base Station Apparatus - Both a wireless terminal apparatus and wireless base station apparatus are provided that can, in an operation of encoding the control signals of the upstream link transmitted from the multiple terminal stations while encoding with regard to each of the terminal stations, increase a number of the terminal stations to which different codes are respectively assigned. A wireless terminal apparatus includes: an encoding information receiving portion receiving encoding information which is used at the wireless terminal apparatus from the base station; a phase-shifting unit which conducts a phase-shifting operation on a predetermined first code based on the encoding information; a code selection unit which, based on the received encoding information, selects a second code from multiple codes orthogonally crossing each other; and a control signal encoding portion which conducts an encoding operation on the control signal that is going to be transmitted to the base station by using both the first code on which the phase-shifting operation has been conducted and the second code. | 05-22-2014 |
20140169150 | METHOD FOR MAPPING PHYSICAL HYBRID AUTOMATIC REPEAT REQUEST INDICATOR CHANNEL - A method for mapping a physical hybrid automatic repeat request indicator channel (PHICH) is described. The method for mapping a PHICH includes determining an index of a resource element group transmitting a repetitive pattern of the PHICH, according to a ratio of the number of available resource element groups in a symbol in which the PHICH is transmitted and the number of available resource element groups in a first or second OFDM symbol, and mapping the PHICH to the symbol according to the determined index. In transmitting the PHICH, since efficient mapping is performed considering available resource elements varying with OFDM symbols, repetition of the PHICH does not generate interference between neighbor cell IDs and performance is improved. | 06-19-2014 |
20140177427 | TRUNCATED ZADOFF-CHU SEQUENCE FOR LTE UPLINK REFERENCE SIGNALS - A method to generate truncated Zadoff-Chu sequences is disclosed. A large Zadoff-Chu sequence is generated, based on a maximum transmission bandwidth, then the sequence is truncated based on the actual transmission bandwidth. The Zadoff-Chu sequence is cyclicly extended, as needed, to maintain a quasi-orthogonal characteristic. The result is that there is an increased number of available Zadoff-Chu sequences for distribution in a wireless neighborhood and the rate of interference is reduced. | 06-26-2014 |
20140334284 | TRANSMITTER AND RECEIVER FOR WIRELESS COMMUNICATION USING REVOLUTION DIVISION MULTIPLEXING, AND SIGNAL TRANSMISSION AND RECEPTION METHOD THEREOF - A signal transmission and reception method includes generating a plurality of electromagnetic wave mode functions having orthogonality in a spatial domain using a plurality of input signals, synthesizing and wirelessly transmitting the generated electromagnetic wave mode functions, receiving a revolution division multiplexing electromagnetic wave having characteristics of phase rotation in directions of an azimuth angle and an elevation angle, and discriminating the electromagnetic wave mode functions through an orthogonal operation, and restoring an output signal through correction of the discriminated electromagnetic wave mode functions. | 11-13-2014 |
20140341010 | SIGNALING OF RANDOM ACCESS PREAMBLE SEQUENCES IN WIRELESS NETWORKS - Transmission of random access preamble structures within a cellular wireless network is based on the use of cyclic shifted constant amplitude zero autocorrelation (“CAZAC”) sequences to generate the random access preamble signal. A pre-defined set of sequences is arranged in a specific order. Within the predefined set of sequences is an ordered group of sequences that is a proper subset of the pre-defined set of sequences. Within a given cell, up to 64 sequences may need to be signaled. In order to minimize the associated overhead due to signaling multiple sequences, only one logical index is transmitted by a base station serving the cell and a user equipment within the cell derives the subsequent indexes according to the pre-defined ordering. Each sequence has a unique logical index. The ordering of sequences is identified by the logical indexes of the sequences, with each logical index uniquely mapped to a generating index. When a UE needs to transmit, it produces a second sequence using the received indication of the logical index of the first sequence and an auxiliary parameter and then produces a transmission signal by modulating the second sequence. | 11-20-2014 |
20140347971 | COMMUNICATION METHOD AND COMMUNICATION APPARATUS - The present disclosure provides an orthogonal codes based code division multiplexing method of performing the code division multiplexing of demodulation reference signals in multiple layers of resource blocks by using orthogonal matrices, the method comprising: changing the order of chips in particular rows of a first orthogonal matrix to obtain a second orthogonal matrix with the changed order of chips; and multiplying the chips in respective rows of the second orthogonal matrix by the demodulation reference signals in corresponding layers of resource blocks correspondingly in the time direction to obtain code division multiplexing signals. The technical scheme of the present disclosure can improve the power jitter situation of downlink signals on the time, thereby the usage efficiency of the power amplifier at the base station side can be improved. | 11-27-2014 |
20140355408 | METHOD OF SCRAMBLING REFERENCE SIGNALS, DEVICE AND USER EQUIPMENT USING THE METHOD - A Method of scrambling reference signals, device and user equipment using the method are provided. In the method, a plurality of layers of reference signals assigned on predetermined radio resource of a plurality of layers of resource blocks with the same time and frequency resources are scrambled, the method comprising: an orthogonalizing step of multiplying each layer of reference signal selectively by one of a plurality of orthogonal cover codes (OCCs) with the same length wherein the OCC multiplied to a first layer of reference signal can be configured as different from those multiplied to other layers of reference signals; and a scrambling step of multiplying all of symbols obtained from the OCC multiplied to each of the other layers of reference signals by a symbol-common scrambling sequence wherein the symbol-common scrambling sequences can be different from each other for reference signals multiplied by the same OCC. | 12-04-2014 |
20150078150 | ALGEBRAIC GENERATORS OF SEQUENCES FOR COMMUNICATION SIGNALS - A device for modulating communication signals comprises a transceiver for receiving and transmitting the signal, a storage medium storing computer implemented programme code components to generate sequences and a processor in communication with the storage medium and transceiver. The processor executes computer implemented programme code components to generate a family of shift sequences or arrays using exponential, logarithmic or index functions and a polynomial in i∈Z | 03-19-2015 |
20150146512 | APPARATUS AND METHOD FOR TRANSMITTING AND RECEIVING OF CYCLIC SHIFT PARAMETER FOR SUPPORTING ORTHOGONALITY IN MIMO ENVIRONMENT - A method includes: determining a Cyclic Shift (CS) parameter that implicitly indicates an orthogonality allocation rule and orthogonality-related information, by determining a multiple access state of a User Equipment (UE), and transmitting the determined CS parameter to the UE, wherein the orthogonality-related information includes an Orthogonal Cover Code indicated by the CS parameter, the orthogonality allocation rule is determined as a uniform scheme or a non-uniform scheme according to the CS parameter, determining the CS parameter by which the non-uniform scheme is applied if the UE is in a Single User Multiple Input Multiple Output state, and determining the CS parameter by which the uniform scheme is applied if the UE is in a Multiple User Multiple Input Multiple Output state. | 05-28-2015 |
20150341147 | COMMUNICATION METHOD AND COMMUNICATION APPARATUS - The present disclosure provides an orthogonal codes based code division multiplexing method of performing the code division multiplexing of demodulation reference signals in multiple layers of resource blocks by using orthogonal matrices, the method comprising: changing the order of chips in particular rows of a first orthogonal matrix to obtain a second orthogonal matrix with the changed order of chips; and multiplying the chips in respective rows of the second orthogonal matrix by the demodulation reference signals in corresponding layers of resource blocks correspondingly in the time direction to obtain code division multiplexing signals. The technical scheme of the present disclosure can improve the power jitter situation of downlink signals on the time, thereby the usage efficiency of the power amplifier at the base station side can be improved. | 11-26-2015 |
20150365947 | System and Method for Orthogonal Frequency Division Multiple Access - An embodiment OFDMA frame includes a header with signal (SIG) fields that are encoded at different sampling rates than one another. In one example, a first signal field is encoded at a 64 point fast frequency transform (FFT) sampling rate, and the second SIG field is encoded at a 256 point FFT sampling rate. The first SIG field may carry parameters for decoding the second SIG field, and the second SIG field may carry resource allocation information for a payload of the OFDMA frame. The first SIG field may carry an identifier of an access point that transmits the OFDMA frame. | 12-17-2015 |
20160028576 | COARSE TIMING - A coarse timing method for a communication system is provided. The coarse timing method may include: calculating timing metric values for received signal samples using a self-correlation based timing metric function; calculating average timing metric values based on previous timing metric values; and determining whether there is a data frame based on the timing metric values and the average timing metric values. | 01-28-2016 |
20160087828 | METHOD OF TRANSMITTING REFERENCE SIGNAL AND TRANSMITTER USING THE SAME - A method and apparatus of transmitting a reference signal in a wireless communication system is provided. A user equipment determines a cell identifier of a cell, and receives a reference signal sequence from the cell. The reference signal sequence is obtained based on 2N+1, where N denotes the cell identifier of the cell. A base station generates the reference signal sequence based on 2N+1, and transmits the reference signal sequence. | 03-24-2016 |
20160173219 | METHOD AND APPARATUS FOR LOW POWER CHIP-TO-CHIP COMMUNICATIONS WITH CONSTRAINED ISI RATIO | 06-16-2016 |
20160173308 | APPARATUS AND METHOD FOR TRANSMITTING AND RECEIVING OF CYCLIC SHIFT PARAMETER FOR SUPPORTING ORTHOGONALITY IN MIMO ENVIRONMENT | 06-16-2016 |
20160173391 | MIMO PGRC SYSTEM AND METHOD | 06-16-2016 |
20160191390 | System and Method for Detecting VOIP Traffic - A system and method of classifying a set of internet protocol network data traffic as likely or unlikely to contain constant-packet-rate data or VoIP traffic using frequency spectrum analysis of data packet arrival times. The method is performed with an apparatus connected in-line on the network link from which the set of network data traffic is obtained. The network data traffic is presorted by packet size, source IP address, destination IP address, source port number, destination port number, or transport-layer protocol to limit the required analysis. A sliding window function is used to provide the time-domain input data to the frequency spectrum analysis. A threshold function is used to detect peaks in the calculated frequency spectrum that indicate constant-packet-rate traffic. An automated system preferably captures the network data traffic from one or more network links, immediately performs the frequency spectrum analysis on the data traffic and stores the results in memory for later access. | 06-30-2016 |
20160197749 | WIRELESS COMMUNICATION SYSTEM, METHOD FOR WIRELESS COMMUNICATION, AND TRANSMITTER | 07-07-2016 |