Patent ID: 7590201

Claim:
A receiver of a multiple input multiple output system for receiving signals by a plurality of receive antennas through a channel when transmission signals are transmitted by a plurality of transmit antennas, the receiver comprising: a first detector for estimating the transmission signal from the received signal with reference to channel information; a first candidate determining unit for determining P constellations close to an output signal of the first detector as first candidates for each transmit antenna, wherein the first candidates including P M combinations in total, P being a number smaller than the number of constellations of a modulation method used by the transmission signals and M being the total number of transmit antennas in the multiple input multiple output system; a second detector for determining a first solution of the received signal among a combination of the first candidates; a second candidate determining unit for determining Q constellations in a direction of the first solution from the output signal of the first detector as second candidates for each transmit antenna, wherein the second candidates including (Q M −1) combinations in total, Q being a number smaller than the number of constellations of a modulation method used by the transmission signals; and a third detector for determining a second solution of the received signal among a combination of the second candidates and detecting the received signal from the second solution.