Feedback of channel state information for mimo and subband scheduling in a wireless communication system

The present invention relates to techniques for sending channel state information efficiently by using the differential encoding. Encoding the difference (differential encoding) across the space, across frequency, across space and frequency, across time, it may be performed across frequency and time, or across other combined dimension. In one design, the spatial state information may be determined for multiple spatial channels on the multiple subbands. Spatial channels of different antennas, etc. may correspond to a different precoding vector. Channel quality indicator (CQI) values ​​can be obtained for multiple spatial channels on the multiple subbands. CQI values ​​may be differential encoding across the multiple spatial channels and the multiple subbands to obtain differential CQI information. In another design, CQI values ​​may be obtained for multiple spatial channels on multiple subbands in multiple time intervals, the space may be differential encoding across frequency and time. The differential CQI information and the spatial state information may be sent as feedback.