Selected Transmission of Multiple Antennas Based on Schmidt Orthogonalization
基于Schmidt正交化的多天线选择复用

A new selected transmission scheme of multiple antennas is proposed, named Greedy Search (GS) method. The transmit antennas selected from all antennas can be used as the active transmit antennas. When used with waterfilling power allocation, GS method can decrease the complexity of signal design on antennas, compared with Waterfilling power allocation on all Antennas (WA). The capacity loss over WA in independent fading channels is rather small, moreover, this method can get capacity gain over WA in spatial dependent fading channels. The cost of capacity gain of GS is the necessity of Schmidt orthogonalization on the channel matrix. GS can be used when the channel matrix is not column-full-rank, i.e., the number of transmit antennas is greater than that of receive antennas, and the transmitter can get the full channel matrix information (used with waterfilling power allocation); or; the receiver can get the full channel matrix information (used with equal power allocation).