Performance improvement methods of sphere decoding in MIMO systems: A technical review.

One of the most effective nonlinear detection techniques utilized in Multi Input Multi Output (MIMO) systems is sphere decoding It consists of a group of very effective algorithms that provide average computational complexity. The realization and deployment of Massive MIMO (M-MIMO) as well as MIMO networks depend greatly on data detection techniques. Different MIMO detectors have been suggested in the literature, based on various principles and approaches. In this paper various sphere decoding algorithms and their performance metrics are illustrated. Also, various sphere decoding methods applied in MIMO systems are compared and pros and cons of each method are presented. Finally, future directions to enhance the effectiveness of sphere decoding algorithms are discussed. We conclude by highlighting a few research challenges and further research directions in this field. [ABSTRACT FROM AUTHOR]