Patent ID: 8891648

Claim:
A system for transmitting and receiving channel state information (CSI), the system comprising: a receiver for receiving a pilot signal transmitted from a transmitter, for estimating CSI of part of downlink channels based on the received pilot signal, for superposing the CSI of part of downlink channels onto an uplink sounding signal orthogonally, and for transmitting the uplink sounding signal superposed with orthogonal sequences carrying the CSI of part of the downlink channels; and the transmitter for obtaining the CSI of a rest part of downlink channels by estimating the uplink sounding signal superposed with orthogonal sequences carrying the CSI of part of downlink channels, for performing orthogonal de-multiplexing on the received signal to obtain the CSI of the part of downlink channels, for, by using the CSI of the two parts of downlink channels, pre-coding downlink data, and for transmitting it to the receiver.