Abstract:
PURPOSE: A codebook design method for an MIMO(Multi-Input Multi-Output) system and a method for using the codebook are provided to use an optimized codebook, thereby accomplishing a high total data transfer rate. CONSTITUTION: A previously designed codebook is stored(S310). The state of a channel formed between a BS(Base Station) and a user is recognized(S320). A transmission rank is adaptively decided(S330). According to an achievable total data transfer rate, the channel state of users, and desired data, the transmission rank is adaptively decided. Based on a plurality of matrixes included into the codebook, a precoding matrix is decided in consideration of channel information and the transmission rank(S340).
Abstract:
다중입출력통신시스템의송신기및 수신기는채널정보를공유하기위해두 개의코드북들을사용한다. 특히, 송신기가 8 개의전송안테나들을사용하는경우, 두개의코드북들이정의될수 있다. 뿐만아니라, 수신기가두 개의코드북들로부터두 개의 PMI들을생성하는경우, 두개의 PMI들의조합은하나의프리코딩매트릭스를지시한다. 프리코딩매트릭스의후보들역시도정의될수 있다.
Abstract:
기지국및 단말은이전선호코드워드및 이산푸리에변환코드북에포함된코드워드들중 임의의코드워드를기초로회전매트릭스를계산할수 있다. 이때, 레퍼런스코드북은회전매트릭스를이용하여회전됨으로써, 새로운코드북으로변환된다. 또한, 레퍼런스코드북은폴라캡 코드북의코드워드들과이산푸리에변환코드북의코드워드들을포함하며, 이산푸리에변환코드북의코드워드들은회전됨에도불구하고, 여전히이산푸리에변환코드북의원소들로서새로운코드북에포함된다.
Abstract:
PURPOSE: A codebook generating method for a multi-polarized multiple input multiple output (MIMO) system and an apparatus for the same are provided to generate a precoding matrix about multi-polarized antennas using a single polarized precoding matrix, thereby generating the precoding matrix having excellent performance only with a simple operation. CONSTITUTION: A precoding matrix generating unit (530) generates a precoding matrix by combining a single polarized precoding matrix assigned to a diagonal block and a zero matrix assigned to remaining blocks. A precoding matrix restructuring unit (540) restructures the precoding matrix by selecting at least one column vector included in the precoding matrix according to a transmission rank corresponding to the number of transmitting data streams. A phase control unit (560) controls each phase of elements included in a reordering matrix using a diagonal matrix. [Reference numerals] (510) Single polarization precoding matrix assigning unit; (520) Zero matrix assigning unit; (530) Precoding matrix generating unit; (540) Precoding matrix restructuring unit; (550) Rotating precoding matrix generating unit; (560) Phase control unit
Abstract:
PURPOSE: A method and apparatus for mixed analog and digital beam-forming are provided to execute a digital beam-forming process for compensating for other terminals except for a first terminal using an analog beam-forming pre-coder fixed in the first terminal. CONSTITUTION: A pre-processor(124) executes a digital beam-forming process by multiplying a digital beam-forming pre-coder by a second sub carrier. The digital beam-forming pre-coder determines an analog beam-forming pre-coder for compensating for a second sub carrier transmitted to a second receiver. The analog beam-forming pre-coder is optimized for a first sub carrier transmitted to a first received in a parallel symbol stream. An RF(Radio Frequency) chain executes an analog beam-forming process by multiplying an analog beam-forming pre-coder by an analog signal. The analog beam-forming pre-coder is transmitted to one or more RF paths. The analog beam-forming pre-coder is optimized for the first sub carrier. [Reference numerals] (100,102) Encoder; (110,112) Modulator; (120) Stream(M_t); (122) MIMO encoder; (124) Pre-processor; (170) Control unit; (AA) Chain 1; (BB) Chain 2; (CC) Each group includes D antennas; (DD) Phase shifter; (EE) Connection of a data path from an antenna 2 to an antenna D is identical; (FF) Antenna 1; (GG) Antenna D; (L) Layer
Abstract:
PURPOSE: A network multiple input multiple output communication system using beamforming is provided to reduce complexity required by utilization of first beamforming vectors and to use a beamforming vector design method based on L-SLNR. CONSTITUTION: A system calculates an intrinsic normalization factor of each terminal(210). The system obtains first beamforming vectors(220). The system calculates the sum of first powers having the first beamforming vectors(230). The system simply calculates a direction component of the beamforming vector(240). The system obtains a scaling factor. The system calculates an optimal beamforming vector(250). [Reference numerals] (210) Beta_k calculation; (220) Obtaining {V_l,k ^L-SLNR}; (230) Calcuating P_k ^L-SLNR; (240) Calculating W_k; (250) Calculating V_l,k; (AA) Start; (BB) End
Abstract:
PURPOSE: A communication method of partial sharing of data in layer cell environment and a device thereof are provided to transmit a message generated by network coding in a target transmitter based on a target message and a neighbor transmitter message. CONSTITUTION: A target receiver estimates a channel(431). The target receiver determines a PMI(Precoding Matrix Indicator) and a neighbor PMI(432). A target transmitter generates a message by network coding(424). The target transmitter performs a precoding based on the PMI(425). The target receiver separates signals for each space(433). The target receiver detects a target message(434).
Abstract:
PURPOSE: A method for adaptively scheduling based on a coordinated rank in a multi cell communication system and a device thereof are provided to enable a mater base station to schedule first the master terminal which has an identical preferred rank to the transmission rank. CONSTITUTION: When a master terminal belongs to a first master group(460), the mater terminal of the first mater group is scheduled(450), wherein the first master group is defined as a group of master terminals which have an identical preferred rank to a transmission rank. When no master terminal belongs to the first master group, a master terminal of a second master group is scheduled, wherein the second master group is defined as a group of master terminals which have a different preferred rank from a transmission rank. The group information to which a scheduled master terminal belongs and the transmission rank information are transmitted to at least one of slave base stations.