Energy-Efficient Backscatter-Assisted Coded Cooperative-NOMA for B5G Wireless Communications

TL;DR

This paper introduces an energy-efficient backscatter-assisted cooperative NOMA system with an optimization framework and joint coding, significantly improving energy efficiency and error rates in B5G wireless communications.

Contribution

It proposes a novel alternating optimization algorithm and a joint channel coding scheme to enhance energy efficiency and decoding performance in backscatter-enabled cooperative NOMA systems.

Findings

Outperforms traditional systems in energy efficiency.

Achieves low BER with few decoding iterations.

Enhances far user performance with joint coding.

Abstract

In this manuscript, we propose an alternating optimization framework to maximize the energy efficiency of a backscatter-enabled cooperative Non-orthogonal multiple access (NOMA) system by optimizing the transmit power of the source, power allocation coefficients (PAC), and power of the relay node under imperfect successive interference cancellation (SIC) decoding. A three-stage low-complexity energy-efficient alternating optimization algorithm is introduced which optimizes the transmit power, PAC, and relay power by considering the quality of service (QoS), power budget, and cooperation constraints. Subsequently, a joint channel coding framework is introduced to enhance the performance of far user which has no direct communication link with the base station (BS) and has bad channel conditions. In the destination node, the far user data is jointly decoded using a Sum-product algorithm (SPA) based joint iterative decoder realized by jointly-designed Quasi-cyclic Low-density parity-check (QC-LDPC) codes. Simulation results evince that the proposed backscatter-enabled cooperative NOMA system outperforms its counterpart by providing an efficient performance in terms of energy efficiency. Also, proposed jointly-designed QC-LDPC codes provide an excellent bit-error-rate (BER) performance by jointly decoding the far user data for considered BSC cooperative NOMA system with only a few decoding iterations.