Patent application number | Description | Published |
20080304446 | Frequency division communication system - An orthogonal frequency division communication system which enables flexible modification of the ratio of allocation between uplink and downlink transmissions, while maintaining advantages similar to those of TDD (Time Division Duplex) systems, has a base station and a plurality of mobile stations connected by uplinks and downlinks, and a plurality of mutually orthogonal frequencies are allocated, on the frequency axis and on the time axis, to the uplinks and downlinks and to the plurality of mobile stations. | 12-11-2008 |
20090175228 | Base Station And Method Of Assigning Frequencies To Pilot Sequences - A base station that assigns frequencies to UP link pilot signals in a radio communication system, where the base station stores the correlation between each of a plurality of pilot sequences having different Peak to Average Power characteristics and a plurality of frequencies that are used for transmitting the pilot sequence by frequency multiplexing, and makes the correlation between each of said pilot sequences and said assigned frequencies in adjacent cells or sectors different. Moreover, the base station measures the reception quality of signals received from a user terminal, makes reference to the stored correlation and finds a pilot sequence having Peak to Average Power characteristic that correspond to said reception quality, then sends an instruction to the user terminal so that the user terminal transmits the pilot sequence using the frequencies assigned to this pilot sequence. | 07-09-2009 |
20090190685 | MIMO COMMUNICATION SYSTEM AND TRANSMISSION STATION - An imbalanced amplitude is produced to a pair of weighing factors (U | 07-30-2009 |
20090219876 | RADIO RESOURCE ALLOCATION CONTROL APPARATUS AND METHOD AND BASE STATION - A radio resource allocation control apparatus for controlling allocation of radio resources used in communication by a plurality of user equipment in a wireless communication system, the apparatus including a selecting unit for selecting a user equipment to which the allocation is performed by using a priority evaluation formula in which a plurality of user equipment having wireless communication characteristics that have a higher tendency of being selected as a target of the allocation vary when different coefficients are imparted. The apparatus includes a control unit for controlling the coefficients individually for the radio resources. | 09-03-2009 |
20090252112 | RADIO COMMUNICATION METHOD AND A BASE STATION AND USER TERMINAL THEREOF - In a radio communication system, each of user terminals together with transmitting a data signal to a base station using different data transmission band frequencies that are assigned by a base station, performs time-division multiplexing of a pilot signal with the data signal and transmit the resulting signal to the base station. A resource management unit of the base station decides pilot transmission bands for each user terminal so that the pilot transmission band covers the data transmission band for each user terminal by frequency offset, and instructs the user terminal to transmit pilot signals using the decided pilot transmission band frequencies. Thereby the base station can estimate channel for each frequency of the data transmission band using the pilot signal. | 10-08-2009 |
20090287981 | Construction of Parity-Check Matrices for Non-Binarys LDPC Codes - A parity check matrix construction method for constructing a non-binary parity check matrix defining a non-binary LDPC code. In particular, a parity check matrix construction method for setting codewords able to stably give a superior decoding performance is provided. For this reason, the non-binary non-zero elements are selected so that the determinants of the partial matrices corresponding to the cycles in the parity check matrix do not become 0. Due to this, a non-binary parity check matrix able to give large weight codewords is constructed. | 11-19-2009 |
20090303868 | Control Channel Transmission Method And Radio Communication Apparatus - A control channel transmission method in a radio communication apparatus which has a plurality of antennas, including, generating signal which are orthogonal to each other on a frequency axis between each of the antennas; modulating the signal using a control signal corresponding to a control channel respectively; and transmitting the modulated signal from each of the antennas using a single carrier transmission. | 12-10-2009 |
20100040086 | RADIO COMMUNICATION APPARATUS AND COMMUNICATION METHOD - In a radio communication apparatus for forming a frame with a plurality of slots, and inserting a guard interval into each slot along with data for a mobile station to perform communication, a receive state acquisition section acquires a receive state of each mobile station, a frame format decision section decides a frame format of which guard interval length is different for each slot based on the receive state of each mobile station, a slot assignment section assigns each slot of the frame format to data for each mobile station, and a frame format reporting section reports the decided frame format to the mobile stations via a reporting channel. The mobile station identifies the GI length based on the reported frame format and the slot number, removes the guard interval, and performs processing. | 02-18-2010 |
20100107031 | MULTIPLE-INPUT-MULTIPLE-OUTPUT TRANSMISSION USING NON-BINARY LDPC CODING - A wireless communication system constructed by a MIMO antenna system and transmitting information from a transmitter having Nt number of transmitting antennas to a receiver | 04-29-2010 |
20100172373 | CONTROL DATA COMMUNICATION METHOD AND APPARATUS THEREOF - A control data communication method for multiplexing and transmitting a plurality of mutually independent types of control data by using a control channel and for separating the control data received from the control channel includes changing and transmitting patterns of reference signals included in the control channel according to a format for multiplexing the control data, detecting the format for multiplexing the transmitted control data according to the pattern of the reference signals included in the control channel, and separating the control data in correspondence with the detected format. | 07-08-2010 |
20100309865 | TERMINAL DEVICE AND BASE STATION DEVICE - A base station measures a signal to interference power ratio using a control signal received from a terminal device through wireless communication, and decides an MCS value indicating a combination of a modulation scheme and a channel code rate. The base station includes the decided MCS value in uplink-channel transmission information and transmits the MCS value to the terminal device by using a control channel including downlink scheduling information. The terminal device decides a transmission format of an uplink data channel based on the MCS in the uplink-channel transmission information. The terminal device, when having received a downlink data channel from the base station, decides a response content (ACK/NACK/DTX) to the base station, based on the result of decoding the downlink data channel. Thereafter, the terminal device transmits the decided response content to the base station through the uplink data channel using the decided transmission format. | 12-09-2010 |
20110053589 | BASE STATION, COMMUNICATION SYSTEM, AND COMMUNICATION METHOD - A base station used in a communication system wherein user terminals are classified into cell center terminals and cell edge terminals, based on reception quality and includes a receiving unit that receives cell edge band information transmitted from another base station and indicative of a cell edge band allocated to a cell edge terminal in a nearby cell; a determining unit that determines a cell edge band for a cell of the base station, based on the cell edge band information for a plurality of nearby cells and received by the receiving unit; and a communicating unit that, via the cell edge band determined by the determining unit, communicates with the cell edge terminals in the cell of the base station. | 03-03-2011 |
20110135041 | RECEIVER AND METHOD FOR RECEIVING - A procedure of receiving includes estimating a phase offset of a received signal and calculating one or more phase offsets which result in the estimated phase offset of the received signal and which have different phase rotation directions and/or different phase rotation amounts from one another; compensating for the phase offset of the received signal, using each of a plurality of phase offsets that are the estimated phase offset and the calculated phase offsets, and demodulating and decoding the plurality of compensated received signals; and selecting a decoding result that is the most likely to be the received signal among a plurality of results of the decoding corresponding one for each of the plurality of phase offsets. | 06-09-2011 |
20110218007 | BASE STATION DEVICE AND METHOD FOR ALLOCATING COMMUNICATION BAND - A base station device is provided with a receiver, an interference comparator, an allocation unit, and a transmitter. The receiver receives an interference parameter indicating a level of interference of the first mobile station with the second mobile station. The interference comparator compares the interference parameter with a predetermined interference threshold value. The allocation unit allocates a communication band to the first mobile station such that the probability that the first band will be allocated to the first mobile station becomes larger than the probability that the second band will be allocated to the first mobile station when a level of interference represented by the interference parameter is larger than a level of interference represented by the interference threshold value. The transmitter transmits information of an allocated band to the first mobile station. | 09-08-2011 |
20110249704 | SPREAD CODE ALLOCATING METHOD, DESPREADING METHOD, TRANSMITTING DEVICE, RECEIVING DEVICE, COMMUNICATING DEVICE, WIRELESS BASE STATION DEVICE, AND MOBILE TERMINAL DEVICE - A communication system, including a transmitter that transmits a signal by using a two-dimensional spread code used for making a spread in time and frequency directions and a receiver that receives the signal transmitted from the transmitter, where the transmitter includes a selecting unit that selects spread codes in which at least one of the time and the frequency directions are mutually orthogonal, and a transmitting unit that spreads a signal by using the selected spread codes and transmits the signal, where each of the selected spread codes are able to be split in two or more parts, which are mutually orthogonal with the same parts of other selected spread codes in at least one of the time and the frequency directions. | 10-13-2011 |
20120147837 | RADIO COMMUNICATION METHOD AND A BASE STATION AND USER TERMINAL THEREOF - A user terminal in a radio communication system, in which each of user terminals performs multiplexing of a data signal and a pilot signal and transmits the multiplexed signal to a base station using different data transmission band frequencies that are assigned by the base station, the user terminal includes a receiving unit that receives uplink resource information from a base station. A pilot generation unit that generates a pilot signal based on the uplink resource information and a transmitting unit that transmits the pilot signal generated by the pilot generation unit to the base station where the pilot generation unit includes a sequence generation unit that generates a Zadoff-Chu sequence as a pilot signal based on the uplink resource information and a subcarrier mapping unit that performs mapping of a sequence generated by cyclically copying the Zadoff-Chu sequence. | 06-14-2012 |
20120201185 | RADIO COMMUNICATION SYSTEM, SERVER, AND RADIO COMMUNICATION METHOD - A radio communication system includes a first server and a second server. The first server includes a first processor to receive, together with an identifier for identifying a base station, communication information transmitted from a plurality of mobile stations via the base station, extract, for the base station, a keyword frequently used in communications between the first server and the plurality of mobile stations on the basis of the received communication information and the received identifier, and transmit the extracted keyword together with the identifier. The second server includes a second processor to receive, together with the identifier, the keyword transmitted from the first server, and distribute distribution information corresponding to the received keyword to the plurality of mobile stations via the base station. | 08-09-2012 |
20120230281 | BASE STATION APPARATUS AND COMMUNICATION METHOD - A base station apparatus performs radio communications with multiple mobile stations using a multi-input multi-output (MIMO) technique. The base station apparatus includes a scheduler configured to assign a mobile station to a first stream over a first frequency band or a second stream over a second frequency band included in the first frequency band, in accordance with the level of interference of the mobile station with a neighbor cell. | 09-13-2012 |
20120281684 | RADIO COMMUNICATION METHOD AND A BASE STATION AND USER TERMINAL THEREOF - A radio communication method in a radio communication system in which data signals for a first and second user are respectively transmitted using first and second subcarrier groups, and pilot signals for the first and second users are multiplexed using time-division multiplexing with the data signals for those users, including arranging a pilot signal of the first user at frequencies different from frequencies of a pilot signal of the second user and mapping subcarrier components of the pilot signals so that one of subcarrier components of higher frequencies corresponds to one of subcarrier components of lower frequencies, wherein the pilot signals are generated using a Zadoff-Chu sequence. | 11-08-2012 |
20130094465 | RADIO COMMUNICATION METHOD AND A BASE STATION AND USER TERMINAL THEREOF - A radio communication system where a terminal transmits a data signal to a base station using data transmission band frequencies assigned by the base station, and performs time-division multiplexing of a pilot signal with the data signal and transmits the resulting signal to the base station. Including deciding a pilot transmission band for the user terminal covering the data transmission band of the user terminal by frequency offset; and instructing the user terminal to transmit the pilot signal using the decided pilot transmission band. A CAZAC sequence is used as the pilot signal. The instructing includes calculating a frequency offset amount for the user terminal, and a cyclic shift amount of the CAZAC sequence and the frequency offset amount; instructing the user terminal to perform cyclic shift of the CAZAC sequence by the cyclic shift amount, and perform frequency offset of the pilot transmission band by the frequency offset amount. | 04-18-2013 |
20140056262 | RADIO COMMUNICATION METHOD AND A BASE STATION AND USER TERMINAL THEREOF - A wireless communication method for transmitting data signals of first and second users using first and second subcarrier groups, respectively, and transmitting pilot signals of the first and second users by multiplexing the pilot signals to the data signals, including allocating the pilot signals of the first and second users to different frequencies, where each of the pilot signals is generated based on Zadoff-Chu sequence; and mapping subcarrier components of the pilot signals so that one or more subcarrier components of higher frequencies and one or more subcarrier components of lower frequencies in the transmission band become identical, in regard to the pilot signals of each of the first and second users. | 02-27-2014 |