Work

Power Allocation Optimization for Secure OFDM-NOMA Downlink Systems

Year: 2025

Type: article

Abstract: Non-orthogonal multiple access (NOMA) is considered as an important enabling technique for the sixth generation wireless network. In this paper, we study a secure orthogonal frequency division multiplexing (OFDM)-NOMA downlink system, which combines OFDM modulation and NOMA technique. In the system, the central user (CU) is an entrusted user and the cell-edge user (EU) is a potential eavesdropper. Due to the use of OFDM modulation, the CU may have weak subcarriers and the EU may have strong subcarriers. Our objective is to maximize both the achievable secrecy rate of CU and achievable rate of EU through power allocation optimization. For the non-convex optimization problem, we propose a sequential parametric convex approximation (SPCA)-based algorithm, a Lagrangian dual transformation (LDT)-based algorithm, and a prime decomposition-based algorithm. Simulation results demonstrate that the proposed LDT-based and prime decomposition-based algorithms, while have much lower computation complexity than the SPCA-based algorithm, achieve the same performance as the latter. Furthermore, it is found that our proposed OFDM-NOMA system outperforms the conventional OFDM-orthogonal multiple access system.

Source: IEEE Open Journal of the Communications Society

Authors: Hanxue Yue, Cheng Guo, Quanzhong Li, Hao Chen, Qi Zhang

Institutions: Sun Yat-sen University, Peng Cheng Laboratory

Language: English

Topic: Wireless Communication Security Techniques

Subfield: Electrical and Electronic Engineering

Field: Engineering

Domain: Physical Sciences

Open Access status: gold

Estimated APC paid: $2,075

Funders: National Natural Science Foundation of China, Basic and Applied Basic Research Foundation of Guangdong Province

Awards: G4866556796, G5027595292, G5602722825