QRD-QLD searching based sphere detector for MIMO receiver

An apparatus comprising:

• a receiver configurable to receive signals from y pairs of antennas, where y is greater than one, and where the received signals convey coded bits of information;
• and
• a detection block comprised of a plurality of search modules configurable to process signals received from pairs of the antennas in parallel to find partial Euclidian distances and determine valid partial candidates for individual antennas;
• a plurality of sort modules configurable to sort the valid partial candidates to find M best partial candidates to be combined into M2 final candidates;
• and further comprising a plurality of a posteriori probability function units arranged to process the M2 final candidates in parallel, with corresponding final Euclidian distances, to determine a posteriori reliability information for coded bits.

A computer-readable memory medium that stores program instructions the execution of which result in operations that comprise:

• simultaneously processing signals received from y pairs of antennas, where y is greater than one and where the received signals convey coded bits of information, to find partial Euclidian distances and determine valid partial candidates for individual antennas;
• sorting valid partial candidates to find M best partial candidates;
• combining the M best partial candidates into M2 final candidates;
• and
• using the M2 final candidates in parallel in a plurality of a posteriori probability function units, with corresponding final Euclidian distances, to determine a posteriori reliability information for coded bits.

An apparatus, comprising:

• means for simultaneously processing signals received from y pairs of antennas, where y is greater than one and where the received signals convey coded bits of information, for finding partial Euclidian distances and determining valid partial candidates for individual antennas;
• means for sorting valid partial candidates to find M best partial candidates;
• means for combining the M best partial candidates into M2 final candidates;
• and
• means for using the M2 final candidates in parallel in a plurality of a posteriori probability function units, with corresponding final Euclidian distances, for determining a posteriori reliability information for coded bits and outputting soft decoded bits to an outer channel decoder.