Soft sphere decoder for MIMO maximum likelihood demodulation

摘要

Methods and apparatus are provided for soft-decision maximum likelihood demodulation to decode a data vector transmitted in a multiple-input multiple-output (MIMO) communications channel. Soft-decision demodulators are disclosed that implement sphere decoding to reduce complexity of demodulation while preserving optimal performance. Candidate signal values associated with the transmitted data vector may be obtained and partitioned into signal bit groups. A sphere search may be performed over the candidate signal values within a search radius value to determine a smallest distance metric for each signal bit group. The search radius value may be updated based on a current smallest distance metric for each signal bit group. A log-likelihood ratio (LLR) may be computed from the determined smallest distance metrics for each signal bit group using a soft-decision demodulator.

主权项

1. A method for decoding a data vector by a processor, the method comprising:
partitioning candidate signal values of the data vector into at least a first partition and a second partition, wherein candidate signal values in the first partition have a same, first symbol value at a particular symbol position, and candidate signal values in the second partition have a same, second symbol value at the particular symbol position; determining a maximum radius value of a first radius associated with the first partition and a second radius associated with the second partition; generating a representation of the plurality of candidate signal values, wherein the representation comprises a first portion representing the first partition and a second portion representing the second partition; and performing a search based on the generated representation of the candidate signal values and the maximum radius value to compute decoding information for the data vector.