A Universal Receiver for Uplink NOMA Systems

TL;DR

This paper proposes a universal turbo-like iterative receiver with an expectation propagation algorithm for uplink NOMA systems, improving performance across various schemes with efficient complexity and fast convergence.

Contribution

It introduces a universal receiver framework and a novel EPA detector suitable for all uplink NOMA schemes, enhancing performance and implementation simplicity.

Findings

EPA receiver outperforms traditional MMSE-PIC in BLER

Achieves fast convergence and low complexity

Compatible with various NOMA schemes

Abstract

Given its capability in efficient radio resource sharing, non-orthogonal multiple access (NOMA) has been identified as a promising technology in 5G to improve the system capacity, user connectivity, and scheduling latency. A dozen of uplink NOMA schemes have been proposed recently and this paper considers the design of a universal receiver suitable for all potential designs of NOMA schemes. Firstly, a general turbo-like iterative receiver structure is introduced, under which, a universal expectation propagation algorithm (EPA) detector with hybrid parallel interference cancellation (PIC) is proposed (EPA in short). Link-level simulations show that the proposed EPA receiver can achieve superior block error rate (BLER) performance with implementation friendly complexity and fast convergence, and is always better than the traditional codeword level MMSE-PIC receiver for various kinds of NOMA schemes.