Patent ID: 7729458

Claim:
A signal decoding apparatus comprising: signal input means for inputting M mixed signals of which L transmission signals which have been obtained from a predetermined information signal and which are independent from each other have been mixed; signal decoding means for decoding the M mixed signals into L separated signals corresponding to the L transmission signals; and channel response estimation means for estimating in parallel a channel response matrix made of M rows times L columns used in the signal decoding means for at least part of the L transmission signals, wherein the channel response estimation means includes: (a) initial channel estimation means for initially estimating an element of the channel response matrix based on a known symbol in the M mixed signals, wherein said signal decoding means detects a transmission signal based on said initially estimated element; (b) replica generation means for performing a transmission process for the L separated signals such that transmission signal replicas of the L transmission signals are generated; (c) co-channel interference component cancellation means for cancelling a co-channel interference component with the transmission signal replicas and the mixed signals; (d) calculation means for obtaining an instantaneous channel response estimation value from a signal of which the co-channel interference component has been cancelled and the transmission signal replicas; and (e) means for: (i) obtaining an instantaneous estimation value which satisfies a predetermined update condition against the instantaneous channel response estimation value; and (ii) supplying a time-average value of the obtained instantaneous evaluation values as an element of the channel response matrix to the signal decoding means.