Title:
Downlink Multiple Access with Simple Receiver Processing for Next Generation Wireless Systems
Abstract:
Downlink multiple access remains an active research area to meet the demanding requirements of high throughput, heterogeneity of quality of service, and massive connectivity for future wireless networks. After reviewing the current schemes used in the first generation (1G) to fifth generation (5G) cellular systems, this talk presents two recent advances.
First, we will review rate-splitting-multiple-access (RSMA), which is a general and powerful multiple access scheme that contains spatial-division-multiple-access (SDMA) and non-orthogonal-multiple-access (NOMA) as special cases. Relying on linearly precoded rate-splitting with successive-interference-cancellation (SIC), RSMA achieves outstanding performance close to the theoretical boundaries.
Second, we will present our recent work of hierarchical-QAM based multiple access (QAMA), where the base station assigns the bit streams to different users from an adjustable hierarchical quadrature-amplitude-modulation (H-QAM) constellation and all users deploy a simple non-iterative receiver with very low complexity. Through joint symbol mapping of H-QAM constellations and phase-aligned precoding at the multi-antenna transmitter, each receiver observes a different H-QAM constellation with Gray mapping, a unique parallax feature not shared by existing schemes. Thanks to the receiver simplicity and the near-optimal rate region, QAMA is an appealing candidate for 6G cellular and other advanced wireless systems.
Speaker:
Shengli Zhou
Professor, ECE Department, University of Connecticut
Bio:
Shengli Zhou (Fellow, IEEE) received the B.S. and M.Sc. degrees in electrical engineering and information science from the University of Science and Technology of China (USTC), Hefei, China, in 1995 and 1998, respectively, and the Ph.D. degree in electrical engineering from the University of Minnesota (UMN), Minneapolis, MN, USA, in 2002.
He is currently a professor with the Department of Electrical and Computer Engineering, University of Connecticut (UCONN), Storrs, CT, USA. His general research interests include wireless communications and signal processing. He received the 2007 ONR Young Investigator Award and the 2007 Presidential Early Career Award for Scientists and Engineers.
He had served as an Associate Editor of IEEE Transactions on Wireless Communications, IEEE Transactions on Signal Processing, and IEEE Journal of Oceanic Engineering. He recently served as the technical co-chair for the 24th IEEE International Workshop on Signal Processing Advances in Wireless Communications (SPAWC), Shanghai, Sept. 2023.
Host: Professor Alex Wyglinski