Low-complexity dominance-based Sphere Decoder for MIMO Systems

TL;DR

This paper introduces the king sphere decoder (KSD), an improved low-complexity sphere decoding method for MIMO systems that reduces computational effort while maintaining detection performance.

Contribution

It proposes the KSD, an enhanced sphere decoder utilizing dominance conditions to significantly lower complexity without sacrificing accuracy.

Findings

KSD reduces computational complexity compared to traditional SD.

Numerical simulations confirm significant complexity savings.

KSD maintains detection performance similar to standard SD.

Abstract

The sphere decoder (SD) is an attractive low-complexity alternative to maximum likelihood (ML) detection in a variety of communication systems. It is also employed in multiple-input multiple-output (MIMO) systems where the computational complexity of the optimum detector grows exponentially with the number of transmit antennas. We propose an enhanced version of the SD based on an additional cost function derived from conditions on worst case interference, that we call dominance conditions. The proposed detector, the king sphere decoder (KSD), has a computational complexity that results to be not larger than the complexity of the sphere decoder and numerical simulations show that the complexity reduction is usually quite significant.