A Review of Sphere Decoding for MIMO Systems and Its Improvement

The sphere decoding algorithm for signal transmitted on multiple antennas channel is considered. In this paper, the preprocessing stage is analyzed in order to seek a reduced complexity and some improvements are made to enhance the performance. The computer simulation results show that the improved algorithm by applying Pohst Enumeration with selected initial radius is more efficient than that by applying Schnorr-Euchner Enumeration. For example, the average floating-point operations in 6 × 6 MIMO using 64-QAM modulation reduces 71% compared with SE enumeration.