Abstract: A Multi-Input Multi-Output (MIMO) downlink transmission control method that is related to communications technologies is disclosed in embodiments of the present invention. The method includes: obtaining a channel fading change rate and a feedback delay of a user; calculating out a closed-loop MIMO throughput gain according to the channel fading change rate and the feedback delay; and determining a downlink transmission mode according to the closed-loop MIMO throughput gain, wherein the downlink transmission mode includes a closed-loop mode or an open-loop mode. A MIMO downlink transmission control apparatus is also disclosed.

Abstract: The present invention provides methods and devices for transporting data from a station (hereinafter source station) to another station (hereinafter target station) by using a transporter. According to the present invention, route information of the transporter is provided to the source station, and the source station determines whether to use the transporter for transporting the data from the source station to the target station.

Abstract: A method for communicating between first multiple nodes and second multiple nodes in a wireless communication system is disclosed. The method includes the steps of performing a first local sharing procedure for a virtual MIMO (Multiple Input Multiple Output) feedback among the second multiple nodes during a first predetermined time; performing feedback of channel status information from the second multiple nodes to the first multiple nodes during a integer multiple of a second predetermined time; and performing a second local sharing procedure for the virtual MIMO feedback among the first multiple nodes during the first predetermined time.

Abstract: In a closed-loop wireless communication system, a codebook-based feedback mechanism is provided to enable non-unitary precoding for multi-stream transmission, where in each stream is optimized with suitable transmission power allocation and AMC. The codebook-based feedback mechanism uses a precoding codebook having a power allocation matrix which is constrained to specify that beamforming always applies full power to a predetermined beam. With this constraint, a one-bit power allocation feedback index may be used to switch between beamforming and spatial multiplexing.

Abstract: A feedback method for interference alignment in wireless network having K transmitters and K receivers is provides. The method comprising: transmitting, performed by transmitter n?1, a precoding vector of transmitter n?1 (n is a integer between 2 and K?1) to receiver n+1; calculating, performed by the receiver n+1, a precoding vector of transmitter n using the precoding vector of transmitter n?1; and transmitting, performed by the receiver n+1, the precoding vector of transmitter n to transmitter n.

Abstract: A power control method for interference alignment in wireless network having K transmitters and K receivers is provided. The method comprising: receiving, performed by receiver n (n is an integer, 1?n?K?1), a power indication signal of transmitter n+1 from the transmitter n+1; determining, performed by the receiver n, power of transmitter n; and transmitting, performed by the receiver n, a power indication signal of transmitter n to the transmitter n, wherein the power of transmitter n is determined based on a residual interference of the receiver n, and the power indication signal of transmitter n indicates a minimum transmission power or a maximum transmission power of transmitter n.

Abstract: A channel information feedback method, an information processing method, a mobile station, a base station, and a MIMO system are disclosed by embodiments of the present invention. Through the foregoing technical solutions, different numbers of channel information feedback bits are allocated for different channels dynamically, and the feedback gain is made better use of.

Abstract: A method for interference alignment in wireless network having 3 transmitters and 3 receivers which are equipped with M antennas is provided. The method comprising: transmitting, performed by each of the 3 transmitters, a pilot signal known to the 3 receivers; estimating, performed by each of the 3 receivers, each channel from transmitter; transmitting, performed by each of the 3 receivers, feedback information to target transmitter; and determining, performed by transmitter 2 and transmitter 3, a precoding vector; wherein a degree of freedom(DoF) of a transmitter 1 is (M/2??), a DoF of the transmitter 2 or the transmitter 3 is M/2.

Abstract: In a closed-loop wireless communication system, a codebook-based feedback mechanism is provided to enable non-unitary precoding for multi-stream transmission, where in each stream is optimized with suitable transmission power allocation and AMC. The codebook-based feedback mechanism uses a precoding codebook having a power allocation matrix which is constrained to specify that beamforming always applies full power to a predetermined beam. With this constraint, a one-bit power allocation feedback index may be used to switch between beamforming and spatial multiplexing.

Abstract: A Multi-Input Multi-Output (MIMO) downlink transmission control method that is related to communications technologies is disclosed in embodiments of the present invention. The method includes: obtaining a channel fading change rate and a feedback delay of a user; calculating out a closed-loop MIMO throughput gain according to the channel fading change rate and the feedback delay; and determining a downlink transmission mode according to the closed-loop MIMO throughput gain, wherein the downlink transmission mode includes a closed-loop mode or an open-loop mode. A MIMO downlink transmission control apparatus is also disclosed.

Abstract: A channel information feedback method, an information processing method, a mobile station, a base station, and a MIMO system are disclosed by embodiments of the present invention. Through the foregoing technical solutions, different numbers of channel information feedback bits are allocated for different channels dynamically, and the feedback gain is made better use of.

Abstract: In a closed-loop wireless communication system, a codebook-based precoding feedback compression mechanism is provided to remove redundancy from the precoding feedback that is caused by channel correlation in time and frequency. Redundancy due to temporal correlation of the transmission channel is removed by sending precoding feedback only if there is a change in the precoder state for the channel to the receiver. Redundancy due to frequency correlation is removed by run length encoding the precoding feedback, thereby compressing the precoding feedback prior in the frequency domain. By compressing the precoding feedback, the average rate of precoder feedback is reduced.

Abstract: In a closed-loop wireless communication system, a codebook-based feedback mechanism is provided to enable non-unitary precoding for multi-stream transmission, where in each stream is optimized with suitable transmission power allocation and AMC. The codebook-based feedback mechanism uses a precoding codebook having a power allocation matrix which is constrained to specify that beamforming always applies full power to a predetermined beam. With this constraint, a one-bit power allocation feedback index may be used to switch between beamforming and spatial multiplexing.

Abstract: In a closed-loop wireless communication system, a codebook-based feedback mechanism is provided to enable non-unitary precoding for multi-stream transmission, where in each stream is optimized with suitable transmission power allocation and AMC. The codebook-based feedback mechanism uses a precoding codebook having a power allocation matrix which is constrained to specify that beamforming always applies full power to a predetermined beam. With this constraint, a one-bit power allocation feedback index may be used to switch between beamforming and spatial multiplexing.

Abstract: In a closed-loop wireless communication system, a codebook-based feedback control mechanism is provided where feedback from each of a plurality of receivers is scheduled to control the feedback so that the receiving devices do not needlessly feed back precoding information to the transmitting device. The feedback may be controlled by establishing and distributing a schedule to control when each receiver feeds back preceding information, or by establishing and distributing a metric-based feedback threshold that must be satisfied before feedback is permitted.

Abstract: A method and apparatus for performing space division multiple access in wireless communications are disclosed. After the receipt of a set of training data from a base station, an estimated channel state information (CSI) is then generated by a mobile station. The CSI is subsequently quantized. The mobile station then determines whether or not the quantized CSI falls within a set of thresholds. If the quantized CSI falls within the set of thresholds, the mobile then sends feedback information to the base station to allow the base station to consider the mobile station as one of the mobile station candidates available for data communications. Otherwise, if the quantized CSI falls outside the set of thresholds, the mobile station then discards the quantized CSI.

Abstract: In a closed-loop wireless communication system, a codebook-based precoding feedback compression mechanism is provided to remove redundancy from the precoding feedback that is caused by channel correlation in time and frequency. Redundancy due to temporal correlation of the transmission channel is removed by sending precoding feedback only if there is a change in the precoder state for the channel to the receiver. Redundancy due to frequency correlation is removed by run length encoding the precoding feedback, thereby compressing the precoding feedback prior in the frequency domain. By compressing the precoding feedback, the average rate of precoder feedback is reduced.

Abstract: In a closed-loop wireless communication system, a codebook-based feedback mechanism is provided to enable non-unitary precoding for multi-stream transmission, where in each stream is optimized with suitable transmission power allocation and AMC. The codebook-based feedback mechanism uses a precoding codebook having a power allocation matrix which is constrained to specify that beamforming always applies full power to a predetermined beam. With this constraint, a one-bit power allocation feedback index may be used to switch between beamforming and spatial multiplexing.

Abstract: In a closed-loop wireless communication system, a codebook-based feedback mechanism is provided where each codeword indicates a particular profile to be used to provide a target performance measure (e.g., bit error rate or spectral efficiency) for the transmission channel. This may be accomplished by using a multi-stage quantization process to construct the codewords as a plurality of transmission parameters specifying a MIMO transmission scheme, precoding vector or matrix, power allocation in space/time/frequency, modulation and channel code.

Abstract: A code division multiple-access receiver comprises an analog-to-digital converter for digitising a demodulated spread signal. The analog-to-digital converter is a Sigma-Delta modulator. The receiver also comprises a despreader comprising simple logic gates and an integrator, performing the function of despreading the digitised demodulated spread signal into a digitised baseband signal. The despreader doubles as a Sigma-Delta demodulator and hence eliminates a separate stage of Sigma-Delta demodulation.