Bit-level combining for MIMO systems with HARQ and/or repetition coding

摘要

Systems and methods are provided for decoding signal vectors in multiple-input multiple-output (MIMO) systems, where the receiver has received one or more signal vectors from a common digital information sequence. Each received signal vector is decoded using, for example, a maximum-likelihood decoder to produce log-likelihood ratios. The results of the decoders are combined by addition to produce a final decoding estimate. In some embodiments, each of the received signals may be processed prior to decoding. The disclosed decoding scheme may utilize all received information without increasing hardware complexity.

主权项

1. A method for decoding a signal vector in a multiple-input multiple-output transmission scheme, comprising:
receiving multiple signal vectors corresponding to a common digital information sequence, wherein the multiple signal vectors are received within distinct time intervals; decoding the received signal vectors, wherein decoding a given received signal vector comprises computing soft information for each of the bits in the given received signal vector based on channel information, associated with the given received signal vector; combining the soft information from each decoded signal vector to obtain an estimate of the digital information sequence; requesting retransmission of a subset of information associated with signal vectors received in a first time interval, wherein the subset of information is selected based on a per-bit reliability metric of the digital information sequence for signal vectors received in the first time interval; storing an estimate of the digital information sequence corresponding to signal vectors received in the first time interval; and combining an estimate of the digital information sequence corresponding to signal vectors received in a second time interval with the stored estimate corresponding to the signal vectors received in the first time interval.