METHOD AND DEVICE FOR REDUCING BIT NUMBER OF PRECODING FEEDBACK BASED ON CODEBOOK SEARCH IN MIMO - OFDM SYSTEM

摘要

A method and device for reducing bit number of precoding feedback information based on codebook search in MIMO - OFDM system are used in the space interface communication between user and base station. The user has a channel state information acquiring unit; a channel variation tracing unit which abstracts maximal singular value of corresponding MIMO channel matrix for each OFDM subchannel according to channel state information, regards the maximal singular value as points on a smooth curve according to the order of OFDM subchannels and finds out the pole; a codebook search unit which searches the whole codebook of the subchannel corresponding to the pole, obtains the precoding vector serial number of corresponding whole codebook, divides the subchannels corresponding to the non- pole into several groups according to the order of OFDM subchannels, obtains proper amount sub-codebook serial number of the precoding codebook for those subchannels corresponding to non-pole of each group by means of the method of the sub-codebook construct and search; and a feedback information synthesizing unit which feedbacks the obtained information of a series of codebook vector serial number to the transmitting terminal.