Patent ID: 7787555

Claim:
A receiver of a multi-input multi-output system using multiple antennas, the receiver comprising: a first multiplying unit for multiplying a vector r received via the antenna by a Hermitian matrix Q; a candidate transmitting vector generating unit for detecting a signal on a lowest modulation order transmitting antenna from a received vector y output from the first multiplying unit, creating as many symbol candidates as the modulation order of the detected signal, and generating a candidate transmitting vector using each symbol candidate; a transmitting vector determining unit for obtaining a distance between each candidate transmitting vector generated by the candidate transmitting vector generating unit and the received vector y to determine a final transmitting vector; a demodulating unit for demodulating the transmitting vector determined by the transmitting vector determining unit; and a decision feedback (DF) detecting unit comprising: a second multiplying unit for multiplying the vector y output from the first multiplying unit by Γ − , wherein Γ − indicates multiplying diagonal terms of an R matrix in reverse order; a determining unit for receiving a value output from the second multiplying unit and outputting the candidate transmitting vector according to a certain determination criterion; a third multiplying unit for multiplying the candidate transmitting vector output from the determining unit by an off-diagonal term B, wherein B indicates R−Γ; and a summing unit for summing vector output from the third multiplying unit and the signal output from the first multiplying unit to remove an interference component from a signal detected at a previous stage.