Patent ID: 7809073

Claim:
A multiple input/multiple output (MIMO) communication method based on distributed transmission sources in a centralized base station system for transmitting a downlink data stream in a MIMO mode between M transmitting antennas and a mobile terminal within their coverage area, wherein said mobile terminal has P receiving antennas, M>1 and P>1, a first and second channels from at least two transmitting antennas of the M transmitting antennas to one of said P receiving antennas have different multipath distributions, said method comprising: transmitting a different sub-data stream of M sub-data streams obtained by dividing said downlink data stream from said M transmitting antennas respectively to said mobile terminal by using a same spreading code; estimating a multipath channel matrix, corresponding to said P receiving antennas of the mobile terminal, of channels from said M transmitting antennas to the receiving antenna, which use the same spreading code; and processing transmitted signals corresponding to said M sub-data streams received by the receiving antenna based on said multipath channel matrix of each receiving antenna, to restore said downlink data stream, wherein said step of estimating the multipath channel matrix of each receiving antenna corresponding to the same spreading code comprising: measuring the total number of all the multipath received components, each having a different delay, of actually received transmitted signals corresponding to the same spreading code; and constructing the multipath channel matrix by taking the number of delays as the multipath number of the MIMO system, so that if the signal transmitted by one of the transmitting antennas to the receiving antenna has no multipath component corresponding to one of the delays, a channel parameter corresponding to the transmitting antenna, the receiving antenna and the delay is set as 0, and said transmitting step comprising: adjusting a gain of said M sub-data streams based on an average signal quality measurement of uplink signals from the mobile terminal to said M transmitting antennas, so that average path losses of respective downlink channels are equal.