Optimal Multi-Level Amplitude-Shift Keying for Partially-coherent SIMO Wireless Communication System in Rician Fading Environment

This paper considers a receive diversity wireless communication system in which the transmitter uses a one-sided multi-level amplitude shift keying (ASK) modulation scheme to transmit data symbols over Rician fading channels. A channel magnitude-based receiver structure having partial knowledge of the instantaneous channel gains is employed to detect the received data symbols. The system’s error performance is analyzed by deriving a series-form expression for the symbol error probability (SEP). Further, an optimization framework is proposed to minimize the SEP under the average system energy constraint for obtaining the optimal ASK constellation. Numerical results are presented to corroborate the analytical framework where the superior performance of the optimal ASK constellation over the traditional equally-spaced ASK scheme is studied.

I. Introduction

The 5th generation (5G) and beyond wireless communication system has been continually evolving and incorporating advanced techniques to ensure that it becomes a reliable and efficient wireless network in supporting the emergence of new applications such as ultra-reliable low-latency communications, massive machine-type communications, and enhanced mobile broadband [1]. These applications require a significant amount of energy for data transmission. Hence, over the recent years, there has been a growing need to design low-complex and energy-efficient transceivers capable of achieving green communications [2], [3].