An Improved Expectation Propagation Based Detection Scheme for MIMO Systems

• Published in: IEEE transactions on communications Vol. 69; no. 4; pp. 2163 - 2175
• Main Authors: Yao, Guoqiang, Chen, Hang, Hu, Jianhao
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.04.2021; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Algorithms; Approximation algorithms; Bandwidths; Complexity theory; Expectation propagation; high performance; Inference algorithms; initial parameters selection; Message passing; MIMO (control systems); MIMO communication; MIMO detection; moment matching strategy; Optimization; Propagation; Signal to noise ratio; Wireless communication; Wireless communication systems; Wireless communications
• ISSN: 0090-6778; 1558-0857
• DOI: 10.1109/TCOMM.2020.3048942

Multiple-input Multiple-output (MIMO) technologies play an important role in modern and future wireless communication systems as they can improve the capacity without increasing the bandwidth. MIMO detection is one of the key technologies for MIMO system designs. MIMO detection schemes based on Message Passing (MP) algorithms have attracted extensive attention in recent years. The MIMO detection scheme based on Expectation Propagation (EP), which is also a kind of MP algorithms, has been proved to achieve the Bayes-optimal performance under the conditions of large system limit and compression rate threshold. However, there is improvement space for the detection performance of the EP algorithm when the conditions are not satisfied, which are the common cases in the practical applications. In this paper, when the conditions of the large system limit and compression rate threshold are not satisfied, we analyze the influences of two factors, the initial parameters selection and the moment matching strategy, on the performance of EP based detection scheme. As a result, we propose an improved EP detection scheme based on optimizing the two factors. Simulation results show that the proposed scheme outperforms the original EP detection scheme in different MIMO scenarios.