Patent application number | Description | Published |
20090170437 | SPEED ESTIMATION AND POWER CONTROL BASED ON CQI REPORTS - Systems and methodologies are described that facilitate utilizing different power control algorithms as a function of access terminal speed. For instance, instantaneous Channel Quality Indicator (CQI) reports can be inverted for slow moving access terminals while long-term geometry inversion (e.g., average CQI report inversion) can be utilized for quick moving access terminals. Speed of the access terminal can be estimated based upon time correlation of CQI values. Further, selection of implementing instantaneous CQI inversion or long-term geometry inversion can be based upon the estimated speed of the access terminal. | 07-02-2009 |
20090245195 | TRANSMISSION OF SIGNALING MESSAGES USING BEACON SIGNALS - Techniques for sending signaling messages with beacon signals in a wireless communication network are described. In one design, a transmitter station may map a signaling message (e.g., a reduce interference request) to multiple code symbols. The transmitter station may select multiple resource elements from among a plurality of resource elements based on the multiple code symbols. In one design, each code symbol may be sent across frequency by selecting one of multiple subcarriers in one symbol period. In another design, each code symbol may be sent across time by selecting one of multiple symbol periods on one subcarrier. The transmitter station may generate a beacon signal having transmit power on the selected resource elements and no transmit power on remaining resource elements. The transmitter station may send the beacon signal to at least one receiver station. | 10-01-2009 |
20090285139 | USING GUARD CARRIERS FOR EXTRA CHANNELS - To assist in minimizing interference, a bandwidth range can have guards on either side to reduce leakage into neighboring bandwidth ranges. However, in relatively low power situations the risk of leakage is reduced. Therefore, the guard bandwidths can be used to open new channels upon which information can be transmitted. Thus, there can be a larger amount of bandwidth used while still retaining protective aspects, such as low interference to neighboring bands. Using the guard bandwidth to transmit new channels facilitates backward compatibility since legacy devices do not commonly monitor the guard bandwidth. These techniques can also be used at high power base stations by advertising a larger guard than necessary to legacy devices and using the additionally created guard bandwidth to transmit new channels. | 11-19-2009 |
20090290550 | SYSTEM AND METHOD TO ENABLE RESOURCE PARTITIONING IN WIRELESS NETWORKS - Systems and methodologies are described that facilitate improved resource partitioning and interference management in a wireless communication system. Techniques are described herein for the transmission and use of various types of signaling, such as Access Request commands, Reverse Link Special Resource Utilization Message (R-SRUM) signaling, Forward Link Special Resource Utilization Message (F-SRUM) signaling, and the like, for managing interference associated with range extension, restricted association networks, and other jamming scenarios. As described herein, downlink resource coordination and interference management are accomplished through the use of Access Request or R-SRUM signaling conducted in a unicast or broadcast fashion, and uplink resource coordination and interference management are accomplished through the use of F-SRUM signaling. As further described herein, a clean communication channel such as a Low Reuse Preamble (LRP) channel can be utilized for interference management signaling and/or leveraged for determining timing of various signaling messages. | 11-26-2009 |
20090291640 | SYSTEM AND METHOD TO ENABLE RESOURCE PARTITIONING IN WIRELESS NETWORKS - Systems and methodologies are described that facilitate improved resource partitioning and interference management in a wireless communication system. Techniques are described herein for the transmission and use of various types of signaling, such as Access Request commands, Reverse Link Special Resource Utilization Message (R-SRUM) signaling, Forward Link Special Resource Utilization Message (F-SRUM) signaling, and the like, for managing interference associated with range extension, restricted association networks, and other jamming scenarios. As described herein, downlink resource coordination and interference management are accomplished through the use of Access Request or R-SRUM signaling conducted in a unicast or broadcast fashion, and uplink resource coordination and interference management are accomplished through the use of F-SRUM signaling. As further described herein, a clean communication channel such as a Low Reuse Preamble (LRP) channel can be utilized for interference management signaling and/or leveraged for determining timing of various signaling messages. | 11-26-2009 |
20100008282 | SYNCHRONOUS TDM-BASED COMMUNICATION IN DOMINANT INTERFERENCE SCENARIOS - Techniques for supporting communication in a heterogeneous network are described. In an aspect, communication in a dominant interference scenario may be supported by reserving subframes for a weaker base station observing high interference from a strong interfering base station. In another aspect, interference due to a first reference signal from a first station (e.g., a base station) may be mitigated by canceling the interference at a second station (e.g., a UE) or by selecting different resources for sending a second reference signal by the second station (e.g., another base station) to avoid collision with the first reference signal. In yet another aspect, a relay may transmit in an MBSFN mode in subframes that it listens to a macro base station and in a regular mode in subframes that it transmits to UEs. In yet another aspect, a station may transmit more TDM control symbols than a dominant interferer. | 01-14-2010 |
20100008317 | METHOD AND APPARATUS FOR COMMUNICATING IN A DOMINANT INTERFERENCE SCENARIO - Techniques for supporting communication in a dominant interference scenario are described. A user equipment (UE) may communicate with a first base station and may observe high interference from and/or may cause high interference to a second base station. In one design, the first base station may use a first frequency band, which may overlap at least partially with a second frequency band for the second base station and may further extend beyond the second frequency band. The first base station may send at least one synchronization signal and a broadcast channel in a center portion of the first frequency band for use by UEs to detect the first base station. The second frequency band may be non-overlapping with the center portion of the first frequency band. The first base station may also communicate with at least one UE on the first frequency band. | 01-14-2010 |
20100054161 | SUPPORTING MULTIPLE ACCESS TECHNOLOGIES IN A WIRELESS ENVIRONMENT - Support for multiple wireless access technologies at a common terrestrial radio access network is described herein. By way of example, wireless resources can be reserved in a manner that facilitates transmission of control and reference signals to advanced or emerging-technology user terminals (e.g., LTE-A), while mitigating adverse affects on legacy user terminals (e.g., LTE Release 8). As such, information designated for LTE-A terminals can be embedded in predetermined reserved locations, which exploit known standardized behavior of legacy terminals in expecting information at specific locations. Such reserving of resources can occur typically without the legacy terminals being affected, mitigating or avoiding performance degradation for legacy terminals. | 03-04-2010 |
20100056217 | METHODS AND APPARATUS OF ADAPTING NUMBER OF ADVERTISED TRANSMIT ANTENNA PORTS - Systems and methodologies of intelligently selecting and advertising antenna ports to UEs (e.g., advertising a number of antenna ports to legacy UEs, and another number of antenna ports to new UEs). Such adaptive feature in adjusting the number of antenna ports, enables the base station(s) to intelligently balance requirements of legacy UEs and new UEs (e.g. LTE-A) for an overall efficient operation of the wireless system take as a whole—(e.g., performance gain for new users is deemed an offset for performance degradation for legacy users.) Accordingly, resources that are typically reserved for a Reference Signal (RS) associated with an antenna port, can be freed when such antenna ports are not advertised to the UEs as part of wireless system operation. | 03-04-2010 |
20100074208 | APPARATUS AND METHOD FOR REDUCING OVERHEAD FOR COMMUNICATIONS - A method and apparatus reducing overhead usage associated with communications is provided. The method may comprise generating an acknowledgment (ACK) for a successfully received codeword from a group of codewords or a negative acknowledgement (NACK) for a codeword unsuccessfully received from the group of codewords, and populating a response information matrix with a plurality of response information elements, wherein the response information elements are determined as a function of the generated acknowledgement or negative acknowledgements. | 03-25-2010 |
20100075686 | SYSTEMS AND METHODS FOR UPLINK CONTROL RESOURCE ALLOCATION - Systems and methods of uniquely identifying communication nodes in a wireless communication system are described herein. One embodiment of the disclosure provides a wireless communication apparatus operative in a communication network. The apparatus comprises a transceiver configured to transmit control information over a first frequency range and content data over a second frequency range during a first predetermined time interval. The first frequency range is allocated to carry a first plurality of control blocks for transmitting only the control information. A duration of each of the first plurality of control blocks spans over the entire duration of the first predetermined time interval. The apparatus further comprises a processing circuit configured to direct the control information of the transceiver over the second frequency range for transmission to a base station node. | 03-25-2010 |
20100075706 | REFERENCE SIGNAL DESIGN FOR LTE A - Systems and methodologies are described that facilitate creating antenna ports to correspond to two or more groups of user equipment (UEs). The subject innovation can organize two or more groups of user equipment and signal to each of the two or more groups a respective antenna port. The subject innovation can further communicate mapping information, a reference signal, or delay related to a linear combination in order to identify antenna ports. Based on such communicated information, the reference signal can be decoded in order to identify each antenna port. | 03-25-2010 |
20100080139 | TECHNIQUES FOR SUPPORTING RELAY OPERATION IN WIRELESS COMMUNICATION SYSTEMS - Techniques for supporting operation of relay stations in wireless communication systems are described. In an aspect, a bitmap may be sent by a base station and/or a relay station to identify subframes of at least two types in multiple radio frames. For example, the bitmap may indicate whether each subframe covered by the bitmap is of a first type or a second type. UEs may use the bitmap to control their operation. For example, a UE may perform channel estimation or measurement for the subframes of the first type and may skip channel estimation and measurement for the subframes of the second type. In another aspect, a base station may transmit data and/or control information on resources not used by a relay station to transmit a reference signal. This may avoid interference to the reference signal from the relay station, which may improve performance for UEs communicating with the relay station. | 04-01-2010 |
20100080166 | TECHNIQUES FOR SUPPORTING RELAY OPERATION IN WIRELESS COMMUNICATION SYSTEMS - Techniques for supporting operation of relay stations in wireless communication systems are described. In an aspect, a base station may transmit data to a relay station in a portion of a subframe instead of the entire subframe. The relay station may transmit control information during part of the subframe. The base station may transmit data to the relay station during the remaining part of the subframe. In another aspect, a target termination for a packet may be selected based on data and/or ACK transmission opportunities available for the packet. One or more transmissions of the packet may be sent with HARQ, and ACK information may be sent for the packet. The packet may be transmitted such that it can be terminated prior to the first subframe (i) not available for sending the packet or (ii) available for sending ACK information. | 04-01-2010 |
20100097978 | DATA TRANSMISSION VIA A RELAY STATION IN A WIRELESS COMMUNICATION SYSTEM - Techniques for supporting data transmission via a relay station are described. In an aspect, data transmission may be supported using ACK-and-suspend. A transmitter station sends a first transmission of a packet to a receiver station. The transmitter station receives no ACK information for the first transmission of the packet and suspends transmission of the packet. The transmitter station thereafter receives an indication to resume transmission of the packet and, in response, sends a second transmission of the packet. In another aspect, different ACK timeline may be used when applicable. The receiver station may send ACK information in a designated subframe if available for use or in a different subframe. In yet another aspect, ACK repetition may be used. The receiver may send ACK information in multiple subframes to facilitate reception of the ACK information when the transmitter station is unable to receive one or more of the multiple subframes. | 04-22-2010 |
20100118839 | CONVEYING INFORMATION THROUGH PHASE OFFSET ON PSS RELATIVE TO DL-RS - Systems and methodologies are described that facilitate conveying information utilizing a constant phase offset on Primary Synchronization Signal (PSS). In general, the subject innovation can employ a fixed set of beams and phases in which a PSS and a Secondary Synchronization Signal (SSS) can be transmitted with the fixed set of beams and phases. Furthermore, the phase offset for PSS and SSS can be the same such that legacy user equipment is unaffected or aware of such transmissions. | 05-13-2010 |
20100182903 | METHOD AND APPARATUS FOR TRANSMITTING OVERLOAD INDICATOR OVER THE AIR - Techniques for transmitting overload indicators over the air to UEs in neighbor cells are described. In one design, an overload indicator may be transmitted as a phase difference between at least one synchronization signal and a reference signal for a cell. In another design, an overload indicator may be transmitted as a phase difference between consecutive transmissions of at least one synchronization signal for a cell. In yet another design, an overload indicator may be transmitted by a cell on resources reserved for transmitting the overload indicator. In yet another design, an overload indicator may be transmitted by a cell on a low reuse channel or a broadcast channel. For all designs, a UE may receive overload indicators from neighbor cells, determine the loading of each neighbor cell based on the overload indicator for that cell, and control its operation based on the loading of the neighbor cells. | 07-22-2010 |
20100184380 | MITIGATING INTERCARRIER AND INTERSYMBOL INTERFERENCE IN ASYNCHRONOUS WIRELESS COMMUNICATIONS - Systems and methodologies are described that facilitate mitigating intercarrier and intersymbol interference in symbol transmissions over wireless communications where transmitter and receiver may not be time synchronized. Symbol periods can be extended for transmitting symbols such that an original symbol can be transmitted with one or more duplicated symbols keeping phase continuous, blank symbols, and/or the like. In this regard, multiple receiver windows can be required to receive the symbol such that at least one window has a non-interfered symbol even though timing can be misaligned (e.g., in asynchronous communications channels). Alternatively, the receiver windows can be divided to allow similar receipt of symbols over multiple windows such that one window has a non-interfered symbol. Also, timing misalignment that leads to phase ramping in frequency is accounted for to allow proper demodulation of the symbol. | 07-22-2010 |
20100195600 | METHOD AND APPARATUS FOR MULTIPLEXING LEGACY LONG TERM EVOLUTION USER EQUIPMENT WITH ADVANCED LONG TERM EVOLUTION USER EQUIPMENT - Aspects are disclosed for multiplexing disparate wireless terminals. Resource blocks are mapped according to a hopping pattern. A first and second pair of physical resource blocks are allocated such that the first pair is associated with a first hopping index pair, whereas the second pair is associated with a second hopping index pair. For this embodiment, the first and second hopping index pairs are inversely symmetrical to each other. A pair of distributed resource blocks is also allocated. An assignment is then scheduled that includes a physical resource allocation and a virtual resource allocation. Aspects for operating a wireless terminal are also disclosed. Here, a communication that includes a resource allocation and a reference signal is received. A minimum resource allocation granularity is ascertained from the communication, and a joint channel estimation is based on the reference signal and is a function of the minimum resource allocation granularity. | 08-05-2010 |
20100232384 | CHANNEL ESTIMATION BASED UPON USER SPECIFIC AND COMMON REFERENCE SIGNALS - Systems and methods are disclosed to facilitate wireless communications. The systems and methods include generating one or more user specific reference signals (UE-RS) and one or more common reference signals (CRS) at a transmitting node; transmitting the UE-RS and the CRS to a user (UE) using a transmission scheme in accordance with a mapping function to enable the UE to estimate a channel based upon CRS observations, UE-RS observations, and the mapping function; and transmitting data using the transmission scheme in accordance with the mapping function. | 09-16-2010 |
20100234061 | OVER-THE-AIR OVERLOAD INDICATOR - Methods, systems, apparatus and computer program products are provided to facilitate power control in wireless communication systems. A cell that is experiencing excessive interference conditions may generate an over-the-air overload indicator indicative of interference conditions at the cell. The over-the-air overload indicator is received by one or more user equipment in a neighboring cell. In response, the user equipment determines adjustments to its transmit power that reduce and/or eliminate the interference. This determination may be carried out by the user equipment, by the serving base station, or through cooperation between the user equipment and the serving base station. This Abstract is provided for the sole purpose of complying with the Abstract requirement rules that allow a reader to quickly ascertain the disclosed subject matter. Therefore, it is to be understood that it should not be used to interpret or limit the scope or the meaning of the claims. | 09-16-2010 |
20100238824 | FEEDBACK MECHANISMS FOR BEAMFORMING OPERATION - A method for generating feedback data is described. A downlink message is received from a base station. It is determined whether full channel reciprocity or partial channel reciprocity is enabled at a transmitter. A mode for feedback data generation is determined. Feedback data is generated using the determined mode. The feedback data includes beamforming information. The feedback data is transmitted to the base station. The feedback data may include a channel quality indicator (CQI) and a rank. | 09-23-2010 |
20100246527 | METHODS AND APPARATUS FOR GENERATION AND USE OF REFERENCE SIGNALS IN A COMMUNICATIONS SYSTEM - Apparatus and methods for generation and use of reference signals in a wireless communications system are described. A group-specific reference signal pattern may be generated for provision to a group of UEs or terminals in communication with an eNodeB or base station. The reference signal may be generated based on system parameters. Reference signals may be generated to span multiple contiguous physical resource blocks. | 09-30-2010 |
20100309867 | DATA TRANSMISSION WITH CROSS-SUBFRAME CONTROL IN A WIRELESS NETWORK - Techniques for supporting communication in dominant interference scenarios are described. In an aspect, communication in a dominant interference scenario may be supported with cross-subframe control. Different base stations may be allocated different subframes for sending control information. Each base station may send control messages in the subframes allocated to that base station. Different base stations may have different timelines for sending control messages due to their different allocated subframes. With cross-subframe control, control information (e.g., grants, acknowledgement, etc.) may be sent in a first subframe and may be applicable for data transmission in a second subframe, which may be a variable number of subframes from the first subframe. In another aspect, messages to mitigate interference may be sent on a physical downlink control channel (PDCCH). | 12-09-2010 |
20100309876 | PARTITIONING OF CONTROL RESOURCES FOR COMMUNICATION IN A DOMINANT INTERFERENCE SCENARIO - Techniques for supporting communication in dominant interference scenarios are described. In an aspect, communication in a dominant interference scenario may be supported with time division multiplex (TDM) partitioning of downlink control resources. For TDM partitioning, different base stations may be allocated different time resources. Each base station may send its control information in its allocated time resources and may avoid sending control information (or may send control information at a lower transmit power level) in time resources allocated to other base stations. In another aspect, communication in a dominant interference scenario may be supported with frequency division multiplex (FDM) partitioning of uplink control resources. For FDM partitioning, different base stations may be allocated different frequency resources. In one design, TDM partitioning may be used for downlink control resources, and FDM partitioning may be used for uplink control resources. | 12-09-2010 |
20110205954 | EXTENSION OF UE-RS TO DWPTS - Systems and methodologies are described that facilitate sending and/or receiving user equipment specific reference signals (UE-RSs) in a wireless communication environment. A UE-RS pattern can be selected, yielded, etc. based upon a number of symbols from a subframe utilized for downlink transmission. At least one time domain component of the UE-RS pattern can vary based upon the number of symbols from the subframe utilized for the downlink transmission. For instance, the at least one time domain component can be punctured, time-shifted, and so forth. Further, UE-RSs can be mapped to resource elements of the subframe as a function of the UE-RS pattern. Moreover, a UE can utilize the UE-RS pattern to detect UE-RSs on the resource elements of the subframe. Further, the UE can estimate a channel based upon the UE-RSs. | 08-25-2011 |
20110244877 | METHOD AND APPARATUS FOR USING CHANNEL STATE INFORMATION REFERENCE SIGNAL IN WIRELESS COMMUNICATION SYSTEM - A method for wireless communication is disclosed which includes selecting a first resource pattern comprising resource elements that are non-colocated with a second resource pattern and allocating the first resource pattern to a plurality of antennas for transmitting a channel state information reference signal. | 10-06-2011 |
20110252139 | METHOD AND APPARATUS FOR PUNCTURING DATA REGIONS FOR SIGNALS TO MINIMIZE DATA LOSS - Methods and apparatuses are provided that facilitate puncturing codeblocks in resource blocks for muting or transmitting signals of a disparate technology such that the puncturing similarly impacts the codeblocks. Codeblocks can be mapped in order across frequency in a given data symbol before moving to a next data symbol. In this regard, utilizing data resource elements substantially evenly spaced across frequency and across data symbols in a data resource block for transmitting signals of the disparate technology can substantially equalize impact of the puncturing to related codeblocks. In addition, resources can be allocated to legacy devices, devices with bandwidth, data rate, or quality of service requirements, devices of a certain rank or geometry, etc., based at least in part on the puncturing. Moreover, a modulation and coding scheme can be selected for generating codeblocks based at least in part on the puncturing and its effect on performance. | 10-13-2011 |
20110261673 | MODIFIED SPATIAL DIVERSITY SCHEMES FOR COVERAGE ENHANCEMENT - In one aspect, a method to enhance coverage in a heterogeneous wireless network wireless communication is disclosed. The method includes generating a reference signal indicating a plurality of transmit antenna ports and generating modulation symbols. Modulation symbols are assigned to each of the plurality of transmit antenna ports, in accordance with a spatial diversity coding scheme for the plurality of transmit antenna ports. At least one of the modulation symbols assigned to at least one of the plurality of transmit antenna ports is muted prior to transmission in accordance with the spatial diversity coding scheme. The non-muted modulation symbols and the reference signal are transmitted on the other of the plurality of transmit antenna ports. | 10-27-2011 |
20110274097 | DETECTING AND REPORTING PHYSICAL-LAYER CELL IDENTIFIER COLLISIONS IN WIRELESS NETWORKS - Physical-Layer Cell Identifier (PCID) collisions may occur in a wireless network when two neighboring evolved Node Bs (eNBs) having different Global Cell Identifiers (GCID) select identical PCIDs. Evolved Node Bs may uniquely identify themselves by transmitting on a broadcast channel, such as a Physical Broadcast Channel (PBCH), a pattern of bits corresponding to the eNB's GCID. Individual User Equipments (UEs) may recognize the PCID collision by decoding the PBCH payload to identify different GCID-modulated payloads from two eNBs involved in the PCID collision. Alternatively, UEs may detect PCID collisions in the wireless network by monitoring Primary Synchronization Signals (PSS) and Secondary Synchronization Signals (SSS) on the PBCH for identical signals separated by a relatively large time offset. After detecting a PCID collision, the UEs may attempt by best effort to report the PCID collision, may report to a fallback eNB, or the UEs may use special resources on an uplink channel. | 11-10-2011 |
20110292875 | APPARATUS AND METHOD FOR PHYSICAL BROADCAST CHANNEL (PBCH) DECODING FOR MULTIPLE CELLS - A method of wireless communication includes generating a list of cells for physical broadcast channel (PBCH) decoding. The method also includes allocating memory for decoding and cancelling a subset of cells from the generated cell list. The method further includes storing information related to subsets of cells from the generated list in the allocated memory during different time periods. The allocated memory is sufficient for attempting, at each time period, decoding of each subset of cells and cancelling of decoded cells in each subset. The method further includes cycling through the generated cell list by processing each subset of the cell list during the different time periods. | 12-01-2011 |
20110310831 | PHYSICAL RESOURCE BLOCK (PRB) BUNDLING FOR OPEN LOOP BEAMFORMING - Provided is a method for wireless communication which includes determining a data allocation size available for data to be transmitted, determining a bundling size based at least in part on the data allocation size, and precoding at least one reference signal in bundled contiguous resource blocks of the determined bundling size. The at least one reference signal in resource blocks in each bundle are precoded with a common precoding matrix. | 12-22-2011 |
20110312353 | ENERGY SAVING MODE WITH MAINTAINED NUMBER OF ADVERTISED TRANSMIT ANTENNAS - Certain aspects of the present disclosure provide techniques for wireless communications, wherein first number of transit antennas is advertised, but a different number of transmit antennas are actually used for transmission. | 12-22-2011 |
20120020230 | CHANNEL FEEDBACK BASED ON REFERENCE SIGNAL - Techniques for supporting channel measurement and reporting in a wireless communication system are described. In one design, a cell transmits a cell-specific reference signal (CRS) used for channel estimation and coherent demodulation and a channel spatial information reference signal (CSI-RS) used for channel measurement and channel feedback reporting. The cell may transmit the CSI-RS less frequently than the CRS, or from more antenna ports than the CRS, or on fewer resource elements than the CRS, or a combination thereof. In one design, a user equipment (UE) determines at least one bandwidth part configured for the UE, with each bandwidth part covering at least one subband. The UE receives the CRS and CSI-RS from the cell, determines channel feedback information for the at least one bandwidth part based on the CSI-RS, sends the channel feedback information to the cell, and receives data transmitted by the cell based on the channel feedback information. | 01-26-2012 |
20120020310 | METHOD AND APPARATUS FOR MITIGATING DATA LOSS DURING AUTONOMOUS SYSTEM INFORMATION READING - Techniques for mitigating data loss during autonomous system information (SI) reading by a user equipment (UE) are described. For autonomous SI reading, the UE may autonomously determine when to read system information from neighbor cells and may not inform a serving cell. In one design, the UE may autonomously select a SI reading gap for reading system information from a neighbor cell. During the SI reading gap, the UE may suspend reception of downlink transmission from the serving cell, receive system information from the neighbor cell, and maintain capability to transmit on the uplink to the serving cell. In one design, the serving cell may determine SI reading gaps autonomously selected by the UE for reading system information from neighbor cells. The serving cell may communicate with the UE by accounting for the SI reading gaps of the UE, e.g., may suspend communication with the UE during the SI reading gaps. | 01-26-2012 |
20120020433 | FEEDBACK FOR SUPPORTING SU-MIMO AND MU-MIMO OPERATION IN WIRELESS COMMUNICATION - A method, an apparatus, and a computer program product for wireless communication are provided in which a precoding matrix is determined from a set of precoding matrices with a first throughput based on a reference signal. In addition, a subset of precoding matrices is determined from the set of precoding matrices with a second throughput greater than a fraction of the first throughput based on the reference signal. Furthermore, a precoding matrix is selected from the subset of precoding matrices based on a metric. | 01-26-2012 |
20120021688 | METHOD AND APPARATUS FOR SWITCHING BETWEEN SINGLE USER DETECTION AND MULTI USER DETECTION - Certain aspects of the present disclosure propose methods and apparatuses for detecting whether a user device is scheduled for a single user (SU) multiple-input multiple-output (MIMO) communication mode or for a multi-user (MU) MIMO communication mode. In an aspect, a method for wireless communications is provided which includes measuring, at a first apparatus based on received pilot signals, a first receive power corresponding to a first channel associated with the first apparatus, measuring, based on the received pilot signals, a second receive power corresponding to a second channel associated with at least one potentially present second apparatus, measuring a residual interference based on the received pilot signals, and determining, based on at least one of the first receive power, the second receive power and the residual interference, whether to apply a MU detection or a SU detection for estimating data received at the first apparatus. | 01-26-2012 |
20120027054 | METHOD AND APPARATUS FOR ENABLING SIGNAL PROCESSING IN A MULTIPLE ANTENNA REPEATER - Systems and methodologies are described that enable serving cell selection in a wireless network with a multiple antenna repeater operable to support MIMO communications. In one example, a repeater using orthogonal frequency division multiplexing on the downlink can be equipped to receive, by one or more receive antennas, one or more signals using one or more radio frequency (RF) isolation schemes. The repeater can further be equipped to amplify and delay the one or more signals using one or more combination schemes. Moreover, the repeater can be equipped to transmit, by one or more transmit antennas, the amplified and delayed one or more signals, wherein at least one of the one or more receive antennas or the one or more transmit antennas includes two or more antennas. | 02-02-2012 |
20120039220 | INTERLEAVING FOR RELAY PHYSICAL DOWNLINK CONTROL CHANNEL (R-PDCCH) - Certain aspects of the present disclosure provide methods and apparatus for interleaving control information for one or more nodes. For certain aspects, the control information may comprise one or more Relay Physical Downlink Control Channels (R-PDCCHs) for one or more relay nodes. The interleaving may comprise interleaving Common Reference Signal (CRS)-based R-PDCCH, wherein the resource elements (REs) for CRS and/or Channel State Information Reference Signal (CSI-RS) may be discounted in a physical resource block (PRB). | 02-16-2012 |
20120044928 | DETERMINATION OF NETWORK SYNCHRONIZATION - User equipment (UE) associated with synchronous networks operate in a synchronous mode while UEs associated with asynchronous networks operate in an asynchronous mode. When operating in a synchronous mode, a UE can significantly improve performance of synchronization signal detection, data decoding, and tracking loop management by using the interference cancellation (IC) techniques that are not available in an asynchronous mode of operation. Obtaining synchronization indicators and determining the synchronization status of the current network by UE is disclosed. The determination may be based on the synchronization indicator, whether detected through signal detection, signal measurements, signal analysis, or the like. | 02-23-2012 |
20120046056 | SAMPLE SELECTION FOR SECONDARY SYNCHRONIZATION SIGNAL (SSS) DETECTION - Methods and apparatus for selecting samples for secondary synchronization signal (SSS) detection are described. Several alternatives are provided for efficient cell identifier detection. In a first alternative, multiple bursts of a signal received from a cell are sampled with non-uniform spacing between sampling intervals to determine a sequence for cell identification. In a second alternative, samples of a first and a second signal received from a stronger cell are cancelled, and a sequence for detecting a weaker cell is determined by reducing effects of the samples of a third signal received from the weaker cell which do not overlap with the primary synchronization signal (PSS) or SSS of the stronger cell. In a third alternative, a sequence for detecting a weaker cell is determined by reducing effects of any sampled bursts that correspond to a high transmission power portion of a signal from a stronger cell. | 02-23-2012 |
20120058791 | CHANNEL STATE INFORMATION REFERENCE SIGNALS - In a wireless communication system, from available data resource elements (REs) in a subframe, REs are assigned to transmissions of a reference signal, thereby resulting in a plurality of remaining data REs. Furthermore, REs from the plurality of remaining data REs are assigned for data transmission to a wireless device in groups of a predetermined number of REs such that all assigned data REs within a group are within a predetermined number of symbols of each other in time domain and within a second predetermined number of subcarriers of each other in frequency domain, thereby resulting in at least one ungrouped RE. | 03-08-2012 |
20120076106 | MUTING SCHEMES FOR CHANNEL STATE INFORMATION REFERENCE SIGNAL AND SIGNALING THEREOF - A method of wireless communication is provided which includes establishing a time-frequency muting pattern including at least one data resource element (RE) and transmitting information indicating the time-frequency muting pattern to a user equipment. In some designs, the muting pattern is established by grouping a plurality of resource elements into muting groups such that the time-frequency muting pattern includes the muting groups. | 03-29-2012 |
20120087299 | REFERENCE SIGNAL CONFIGURATION AND RELAY DOWNLINK CONTROL CHANNEL - Aspects of the present disclosure relate to methods for allowing a relay base station to more efficiently decode relay control information transmitted from a donor base station. A relay base station may determine a configuration of resource elements used for transmission of reference signals and decode sets of resource elements based on the configuration of reference signals. According to aspects, a donor base station may transmit relay control information in a data portion of a subframe based on the configuration of reference signals transmitted by the donor base station. | 04-12-2012 |
20120087401 | METHOD AND APPARATUS OF USING CDD LIKE SCHEMES WITH UE-RS BASED OPEN LOOP BEAMFORMING - A method and apparatus of wireless communication are disclosed. The wireless communication performs pilot signal transmissions using a first precoding matrix for user equipment specific pilot signals, the pilot signal transmissions having a first transmission rank. The wireless communication also performs data transmissions using a second precoding matrix for data when the data transmissions have a second transmission rank less than the first transmission rank, in which the second precoding matrix includes a transformed version of the first precoding matrix. Alternatively, the wireless communication can perform data transmissions using at least two precoding matrices for data when the data transmissions have a second transmission rank less than or equal to the first transmission rank. Accordingly, the precoding matrix used for data is a transformed version of the precoding matrix used for user equipment specific pilot signals. | 04-12-2012 |
20120106374 | METHODS AND APPARATUSES FOR USING CHANNEL STATE INFORMATION REFERENCE SIGNALS - In a wireless communication system, a wireless device is identified as being a relay device. A channel state information reference signal (CSI-RS) configuration is selected such that at least one CSI-RS can be transmitted to the wireless device in a subset of subframes assigned to relay backhaul transmissions. | 05-03-2012 |
20120106595 | METHOD AND APPARATUS FOR OPTIMIZING POWER DISTRIBUTION BETWEEN SYMBOLS - A method, an apparatus, and a computer program product for wireless communication are provided in which a first pre-coding matrix for use on a portion of a set of resource blocks (RBs) is determined. At least one beamforming vector of the set of beamforming vectors is modified by applying a phase rotation to generate a modified pre-coding matrix. The modified pre-coding matrix is applied to one or more demodulation reference signals and data associated with the portion of the set of RBs for transmission using at least one antenna. | 05-03-2012 |
20120113816 | REFERENCE SIGNAL RECEPTION AND CHANNEL STATE INFORMATION DETERMINATION FOR MULTIPLE NODES IN A WIRELESS COMMUNICATION NETWORK - Techniques for receiving reference signals from multiple nodes and determining channel state information (CSI) for the nodes are disclosed. A user equipment (UE) may determine and report CSI for the multiple nodes to support data transmission to the UE. The nodes may transmit reference signals based on different configurations. The configuration for each node may indicate when, where, and how the node transmits its reference signal. The UE may determine CSI for different nodes and/or different combinations of nodes based on the reference signals transmitted by these nodes as well as an indication of which subframes to use to determine each CSI reported by the UE. The UE may report different CSIs for different subframes and may receive data transmission sent by a single node or a combination of nodes based on the reported CSIs. | 05-10-2012 |
20120134273 | REFERENCE SIGNAL PATTERNS - Certain aspects of the present disclosure provide techniques for allocating resources for use in transmitting reference signals (RSs). According to certain aspects, a large set of enumerated possible CSI-RS resources (“CSI-RS patterns”) may be defined and a base station may select a CSI-RS pattern from a subset of the available patterns, with the subset determined by a transmission configuration. | 05-31-2012 |
20120163159 | INTERFERENCE RANDOMIZATION FOR UPLINK SIGNALING - A method for transmitting an acknowledgement/negative acknowledgement is described. Cell-specific symbol-level cyclic shift hopping is applied to data single-carrier frequency division multiplexing symbols of the acknowledgement/negative acknowledgement. A discrete Fourier transform is applied to the data single-carrier frequency division multiplexing symbols. Cell-specific symbol-level phase hopping is applied to the data single-carrier frequency division multiplexing symbols. The data single-carrier frequency division multiplexing symbols are transmitted in a slot. | 06-28-2012 |
20120182946 | RATE MATCHING FOR COORDINATED MULTIPOINT TRANSMISSION SCHEMES - Certain aspects of the present disclosure relate to techniques for determining resource elements REs used for Coordinated Multipoint (CoMP) transmission schemes. The techniques generally include determining, by a User Equipment (UE), a set of data REs used for Coordinated Multipoint (CoMP) operation. The determination is based on a CoMP scheme and data REs available to particular base stations involved in the CoMP operation. The technique further includes processing data received via the CoMP operation on the determined set of data REs. | 07-19-2012 |
20120207105 | COOPERATION AND OPERATION OF MACRO NODE AND REMOTE RADIO HEAD DEPLOYMENTS IN HETEROGENEOUS NETWORKS - A method, an apparatus, and a computer program product for wireless communication are provided for separating control transmissions and data transmissions within the coverage area of a plurality of transmission/reception points or points that are geographically displaced, the plurality of points comprising a macro node and a plurality of remote radio heads (RRHs) coupled to the macro node. Separating control transmissions and data transmissions in the macro node/RRH configuration may allow UEs to be associated with one set of transmission points for data transmissions and the same set or a different set of transmission points for common control signaling. Separating control transmissions and data transmissions may also allow for faster reconfiguration of antenna ports used for UE data transmission compared with reconfiguration via a handover process. | 08-16-2012 |
20120263247 | METHOD AND APPARATUS FOR SELECTING REFERENCE SIGNAL TONES FOR DECODING A CHANNEL - Methods and apparatuses are provided that include selecting reference signal (RS) or other tones to utilize in estimating a channel for decoding one or more channels. Where the RS tones are interfered by other base stations, interference cancelation can be performed over the RS tones. Since interference can vary over the tones, interference cancelation can yield RS tones of varying quality. Thus, a quality of each of the RS tones can be determined, and at least a subset of the RS tones can be selected for estimating a channel. Additionally or alternatively, the RS tones can be weighted or otherwise classified for performing channel estimation using the RS tones. | 10-18-2012 |
20130010707 | METHOD AND APPARATUS FOR SIGNALING PAGING CONFIGURATIONS AND CHANNEL STATE INFORMATION REFERENCE SIGNAL (CSI-RS) CONFIGURATIONS - A UE or eNnodeB receives a paging configuration or channel state information reference signal (CSI-RS) configuration of a neighbor cell. The configuration enables calculating when the CSI-RS or muting of the neighbor cell will occur. | 01-10-2013 |
20130021926 | FEEDBACK REPORTING BASED ON CHANNEL STATE INFORMATION REFERENCE SIGNAL (CSI-RS) GROUPS - In macro/RRH setups, channel state information reference signals (CSI-RS) and demodulation reference signals (DM-RS) may be used to decouple control and data transmission. Data transmission (e.g. for LTE Rel 10 and beyond) may be based on CSI-RS and DM-RS, while control may be received from a different set of cells or TxPs via CRS. Certain aspects of the present disclosure introduce a reporting framework, in which configuration of data-serving cells/TxPs may be carried out based on CSI-RS. In certain aspects, a new concept of CSI-RS groups, i.e., a set of CSI-RS ports that a UE considers as one group for precoding matrix indicator (PMI)/channel quality indicator (CQI)/rank indicator (RI) reporting, may be defined. | 01-24-2013 |
20130028182 | IMPLICITLY LINKING APERIODIC CHANNEL STATE INFORMATION (A-CSI) REPORTS TO CSI-REFERENCE SIGNAL (CSI-RS) RESOURCES - Certain aspects of the present disclosure provide techniques for implicitly linking aperiodic channel state information (A-CSI) reports to CSI-reference signal (CSI-RS) resources. In an aspect, the UE may be instructed to report on specific CSI-RS resource(s) via explicit signaling in the UE grant. Other aspects disclose techniques for implicit CSI-RS resource selection by the UE that require fewer signaling resources. Instead of explicitly signaling CSI-RS resources to the UE, the UE may implicitly select CSI-RS resource for CSI feedback reporting based on information known to the UE, e.g. a subframe on which a reporting request is received. This may reduce the impact of the additional signaling in the UE grant. | 01-31-2013 |
20130094427 | METHOD AND APPARATUS FOR COMMUNICATING IN A DOMINANT INTERFERENCE SCENARIO - Techniques for supporting communication in a dominant interference scenario are described. A user equipment (UE) may communicate with a first base station and may observe high interference from and/or may cause high interference to a second base station. In one design, the first base station may use a first frequency band, which may overlap at least partially with a second frequency band for the second base station and may further extend beyond the second frequency band. The first base station may send at least one synchronization signal and a broadcast channel in a center portion of the first frequency band for use by UEs to detect the first base station. The second frequency band may be non-overlapping with the center portion of the first frequency band. The first base station may also communicate with at least one UE on the first frequency band. | 04-18-2013 |
20130095829 | IDLE MODE OPERATION IN HETEROGENEOUS NETWORKS - An idle mode UE can RACH to a cell different from the cell paging the UE. The UE can be allocated additional time to respond to all cells in the neighborhood to identify the cell in which to RACH. Interference cancellation can occur at different rates based on whether the UE is in connected mode or idle mode. The time to respond to the page can be a function of a paging cycle. Additionally, a variable bias may promote early handoff to lower power cells and late handoff to high power cells. | 04-18-2013 |
20130242959 | SYNCHRONOUS TDM-BASED COMMUNICATION IN DOMINANT INTERFERENCE SCENARIOS - Techniques for supporting communication in a heterogeneous network are described. In an aspect, communication in a dominant interference scenario may be supported by reserving subframes for a weaker base station observing high interference from a strong interfering base station. In another aspect, interference due to a first reference signal from a first station (e.g., a base station) may be mitigated by canceling the interference at a second station (e.g., a UE) or by selecting different resources for sending a second reference signal by the second station (e.g., another base station) to avoid collision with the first reference signal. In yet another aspect, a relay may transmit in an MBSFN mode in subframes that it listens to a macro base station and in a regular mode in subframes that it transmits to UEs. In yet another aspect, a station may transmit more TDM control symbols than a dominant interferer. | 09-19-2013 |
20130250793 | METHOD AND APPARATUS FOR SELECTING REFERENCE SIGNAL TONES FOR DECODING A CHANNEL - Methods and apparatuses are provided that include selecting reference signal (RS) or other tones to utilize in estimating a channel for decoding one or more channels. Where the RS tones are interfered by other base stations, interference cancelation can be performed over the RS tones. Since interference can vary over the tones, interference cancelation can yield RS tones of varying quality. Thus, a quality of each of the RS tones can be determined, and at least a subset of the RS tones can be selected for estimating a channel. Additionally or alternatively, the RS tones can be weighted or otherwise classified for performing channel estimation using the RS tones. | 09-26-2013 |
20130250855 | SYNCHRONOUS TDM-BASED COMMUNICATION IN DOMINANT INTERFERENCE SCENARIOS - Techniques for supporting communication in a heterogeneous network are described. In an aspect, communication in a dominant interference scenario may be supported by reserving subframes for a weaker base station observing high interference from a strong interfering base station. In another aspect, interference due to a first reference signal from a first station (e.g., a base station) may be mitigated by canceling the interference at a second station (e.g., a UE) or by selecting different resources for sending a second reference signal by the second station (e.g., another base station) to avoid collision with the first reference signal. In yet another aspect, a relay may transmit in an MBSFN mode in subframes that it listens to a macro base station and in a regular mode in subframes that it transmits to UEs. In yet another aspect, a station may transmit more TDM control symbols than a dominant interferer. | 09-26-2013 |
20130250913 | COOPERATION AND OPERATION OF MACRO NODE AND REMOTE RADIO HEAD DEPLOYMENTS IN HETEROGENEOUS NETWORKS - A method, an apparatus, and a computer program product for wireless communication are provided for separating control transmissions and data transmissions within the coverage area of a plurality of transmission/reception points or points that are geographically displaced, the plurality of points comprising a macro node and a plurality of remote radio heads (RRHs) coupled to the macro node. Separating control transmissions and data transmissions in the macro node/RRH configuration may allow UEs to be associated with one set of transmission points for data transmissions and the same set or a different set of transmission points for common control signaling. Separating control transmissions and data transmissions may also allow for faster reconfiguration of antenna ports used for UE data transmission compared with reconfiguration via a handover process. | 09-26-2013 |
20140161043 | SAMPLE SELECTION FOR SECONDARY SYNCHRONIZATION SIGNAL (SSS) DETECTION - Methods and apparatus for selecting samples for secondary synchronization signal (SSS) detection are described. Several alternatives are provided for efficient cell identifier detection. In a first alternative, multiple bursts of a signal received from a cell are sampled with non-uniform spacing between sampling intervals to determine a sequence for cell identification. In a second alternative, samples of a first and a second signal received from a stronger cell are cancelled, and a sequence for detecting a weaker cell is determined by reducing effects of the samples of a third signal received from the weaker cell which do not overlap with the primary synchronization signal (PSS) or SSS of the stronger cell. In a third alternative, a sequence for detecting a weaker cell is determined by reducing effects of any sampled bursts that correspond to a high transmission power portion of a signal from a stronger cell. | 06-12-2014 |
20140161044 | SAMPLE SELECTION FOR SECONDARY SYNCHRONIZATION SIGNAL (SSS) DETECTION - Methods and apparatus for selecting samples for secondary synchronization signal (SSS) detection are described. Several alternatives are provided for efficient cell identifier detection. In a first alternative, multiple bursts of a signal received from a cell are sampled with non-uniform spacing between sampling intervals to determine a sequence for cell identification. In a second alternative, samples of a first and a second signal received from a stronger cell are cancelled, and a sequence for detecting a weaker cell is determined by reducing effects of the samples of a third signal received from the weaker cell which do not overlap with the primary synchronization signal (PSS) or SSS of the stronger cell. In a third alternative, a sequence for detecting a weaker cell is determined by reducing effects of any sampled bursts that correspond to a high transmission power portion of a signal from a stronger cell. | 06-12-2014 |
20140177519 | REFERENCE SIGNAL RECEPTION AND CHANNEL STATE INFORMATION DETERMINATION FOR MULTIPLE NODES IN A WIRELESS COMMUNICATION NETWORK - Techniques for receiving reference signals from multiple nodes and determining channel state information (CSI) for the nodes are disclosed. A user equipment (UE) may determine and report CSI for the multiple nodes to support data transmission to the UE. The nodes may transmit reference signals based on different configurations. The configuration for each node may indicate when, where, and how the node transmits its reference signal. The UE may determine CSI for different nodes and/or different combinations of nodes based on the reference signals transmitted by these nodes as well as an indication of which subframes to use to determine each CSI reported by the UE. The UE may report different CSIs for different subframes and may receive data transmission sent by a single node or a combination of nodes based on the reported CSIs. | 06-26-2014 |
20140192919 | REFERENCE SIGNAL DESIGN FOR LTE A - Systems and methods are disclosed that facilitate creating antenna ports to correspond to two or more groups of user equipment. The systems and methods can organize two or more groups of user equipment and signal to each of the two or more groups a respective antenna port. The systems and methods can further communicate mapping information, a reference signal, or delay related to a linear combination in order to identify antenna ports. Based on such communicated information, the reference signal can be decoded in order to identify each antenna port. | 07-10-2014 |
20150085948 | METHOD AND APPARATUS OF USING CDD LIKE SCHEMES WITH UE-RS BASED OPEN LOOP BEAMFORMING - A method and apparatus of wireless communication are disclosed. The wireless communication performs pilot signal transmissions using a first precoding matrix for user equipment specific pilot signals, the pilot signal transmissions having a first transmission rank. The wireless communication also performs data transmissions using a second precoding matrix for data when the data transmissions have a second transmission rank less than the first transmission rank, in which the second precoding matrix includes a transformed version of the first precoding matrix. Alternatively, the wireless communication can perform data transmissions using at least two precoding matrices for data when the data transmissions have a second transmission rank less than or equal to the first transmission rank. Accordingly, the precoding matrix used for data is a transformed version of the precoding matrix used for user equipment specific pilot signals. | 03-26-2015 |