Kabushiki Kaisha Toshiba

Yong Sun

Filippo Tosato

Hidehiro Matsuoka

Ngoc-Dung Dao

Fengming Cao

Henning Vetter

According to one embodiment there is provided a method performed in a transmitter side of a multiuser minimum square error linear precoding MIMO system that comprises a transmitter with a plurality of transmit antennae and a plurality of receivers. Each receiver of the plurality of receivers comprises a plurality of receive antennae. The method is a method of scheduling receivers from among the plurality of receivers and comprises obtaining, for some or all of the receivers, receiver channel information that quantifies the properties of transmit channels between receiver antennae of the receiver and transmit antennae of the transmitter and establishing an order for determining the receiver combining vectors of the some or all of the receivers. The order is established by selecting as a next receiver in the order a so far unselected receiver from the some or all of the receivers that minimally increases the mean square data transmission error. The establishing of the order is based on the channel information of any receivers previously selected in the order and of unselected receivers.

Linear multiuser precoding with multiple-receive antenna receivers

Codebook based communication of precoding data between two stations involves determining a 'best fit' precoding at a receiving station, on the basis of channel state measurements taken therein. The best fit precoding is compared with pre-agreed entries in a codebook, and an indicator is sent back to the terminal emitting the analysed signal. The determination is separated into two elements, one being sufficient for use with SU-MIMO, and another being provided, with a second codebook indicator, if MU-MIMO is to be employed. This second codebook indicator points to a codebook of eigenvector representations for the multi-user space in which the channel is persisting.

Dual indicator scheme for channel state information feedback

The present invention provides a method of processing information prior to an emission from a multi-antenna device in a multi-user network having at least one user, said emission comprising transmission of a plurality of subcarriers comprising pilot symbols and data symbols, and said information being a data vector, the method comprising arranging said pilot symbols and said data symbols such that at least one of said plurality of subcarriers comprises at least one of said pilot symbols and at least one of said data symbols, wherein said data vector corresponds to said at least one of said plurality of subcarriers such that said data vector comprises data elements corresponding to said at least one of said pilot symbols and said at least one of said data symbols, precoding said data vector prior to transmission, and the precoding comprising applying a perturbation to said data vector in order to generate a perturbed data vector in which data elements corresponding to the pilot symbol remain unperturbed, and scaling said data vector by means of a precoding matrix.

Wireless communication method and apparatus

The present disclosure concerns the harnessing of the effect of a relay to enhance the ability to avoid the effect of interference at mobile stations. This is achieved either by overlaying beamforming for an indirectly reached mobile station so that a relay passes on this beamforming to the mobile station concerned, and retaining orthogonality therewith, or by harnessing a base station and a relay station together so that their combined effect is to provide spatial multiplexing to two or more mobile stations.

Remotely weighted SDMA transmission

A received signal selector for a received signal, the received signal including a set of carriers, the received signal selector being configured for use with an antenna system including a plurality of antenna elements. The received signal selector includes a plurality of received signal inputs for receiving signals from the plurality of antenna elements, an interference detector for each of the received signals inputs, coupled to the received signal inputs to receive, from each input, a version of the received signal, and configured to provide an interference output for the set of carriers from each input, a selection controller configured to receive the interference output for each input and having a control output, and a selector coupled to the received signal inputs and responsive to the control output to select one or more of the versions of the received signal for output. The invention provides a simplified technique for mitigating the effects of co-channel interference and severe multipath distortion.

Signal selection systems

The invention provides a generic and comprehensive architecture to optimise several space-time adaptive algorithms and their applications for both CCI and ISI interference cancellation for MIMO systems. The basic idea of this invention is to optimise space-only processes and time-only processes and their combination to take account of the varying affects of CCI and ISI in a given environment. This maximises the efficiency of adaptive algorithms. The invention is targeting on unknown CCI or co-antenna interference of other operating system at the same frequency band.

MIMO communication system

Antenna techniques particularly for orthogonal frequency division multiplexed (OFDM) communications systems. A signal processing system determines weights for an adaptive antenna, the antenna including plural antenna elements each receiving a signal including plural subcarriers. The system includes plural inputs for receiving signals from the antenna elements, a time-to-frequency domain transformer for each input for transforming the signal from each input to a plurality of subcarrier signals, a first weight determiner coupled to the inputs, before the time-to-frequency domain transformer in the signal path, and configured to determine a first set of weights, one for each input, and a second weight determiner coupled to the first weight determiner and configured to determine, from the determination of the first set of weights, at least one second set of weights including a frequency-domain weight for a subcarrier signal derived from each of the inputs.

Growing community of inventors

Bristol, United Kingdom

Yong Sun