Abstract: A Log-Likelihood Ratio (LLR) combining method and apparatus for Hybrid Automatic Repeat Request (HARQ) in a wireless communication system for reducing a number of the LLR bits of previous packet stored for LLR combining are provided. The LLR combining apparatus includes an LLR combiner for combining a first LLR of a currently received packet and a second LLR of a previously received packet, an LLR buffer for storing the second LLR and a first packet exponent for recovering the second LLR in the same size as the first LLR, and an HARQ controller for determining whether the currently received packet is a retransmission packet or an initial transmission packet, and for controlling the LLR combiner to generate a third LLR by combining the first and second LLRs for the retransmission packet and to bypass the initial transmission packet.

Abstract: A method of detecting interference in a received sample vector using hidden Markov modelling by first estimating noise variance, where estimating noise variance comprises the steps of receiving a sample vector of noise and interference, sorting the sample vector in the frequency domain by order of increasing magnitude to produce an ordered vector, finding a sub-vector of the ordered vector that minimizes the distance from a noise measure, and estimating the noise variance.

Abstract: A method for communication includes receiving a spatially-multiplexed signal using multiple receivers to produce multiple respective received signals. The spatially-multiplexed signal includes multiple simultaneously-transmitted symbols, which are selected from respective sets of constellation symbols, each constellation symbol representing a respective set of values of a group of data bits. Combinations of the constellation symbols are traversed iteratively. Each combination includes one constellation symbol from each of the sets of the constellation symbols and represents N data bits. The traversed combinations are searched for a combination that matches the received signals. During traversal of the combinations, at least 2N measures of likelihood regarding the values of the data bits represented by each traversed combination are accumulated. The accumulated measures of likelihood are processed to produce soft bit metrics.