Patent ID: 8179992
Filing Date: 2012-05-15
Classification: H04J,H04L

Abstract:
1. A communication apparatus comprising: a plurality of antennas; a plurality of receiving units which are each coupled to one of said plurality of antennas, and which respectively acquire received signals by receiving, via said coupled antennas, a plurality of signals transmitted from a transmitting apparatus having a plurality of antennas; a candidate group setting unit which, based on a first channel matrix describing a communication channel between said plurality of transmitted signals and said plurality of received signals, calculates a first residual component by canceling a component corresponding to a candidate or candidates for a first other transmitted signal or signals other than a first transmitted signal among said plurality of transmitted signals from a first signal corresponding to at least one of said plurality of received signals and having components corresponding to all of said plurality of transmitted signals, determines a candidate for said first transmitted signal by selecting a value closest to said first residual component from among values that said first transmitted signal can take, and constructs a first candidate group as a collection of candidate sets each comprising a candidate for said first transmitted signal and a candidate or candidates for said first other transmitted signal or signals, and which, based on a second channel matrix describing a communication channel between said plurality of transmitted signals and said plurality of received signals, calculates a second residual component by canceling a component corresponding to a candidate or candidates for a second other transmitted signal or signals other than a second transmitted signal among said plurality of transmitted signals from a second signal corresponding to at least one of said plurality of received signals and having components corresponding to all of said plurality of transmitted signals, determines a candidate for said second transmitted signal by selecting a value closest to said second residual component from among values that said second transmitted signal can take, and constructs a second candidate group as a collection of candidate sets each comprising a candidate for said second transmitted signal and a candidate or candidates for said second other transmitted signal or signals; a common group searching unit which constructs a common group by selecting any transmitted signal candidate set that is common between said first candidate group and said second candidate group; a metric calculating unit which, for each transmitted signal candidate set contained in said common group, computes an estimated received signal set corresponding to said each transmitted signal candidate set, and calculates a distance between said estimated received signal set and said plurality of received signals; and a signal estimating unit which estimates that the transmitted signal candidate set that minimizes said distance represents the set of said plurality of transmitted signals.