The Performance of Cooperative-NOMA in Cognitive Hybrid Satellite Networks

Integrating cognitive radio (CR) technology into satellite communication represents an effective approach to enhance the throughput of satellite systems. However, the use of orthogonal multiple access (OMA) in traditional satellite-based CR systems has posed limitations on satellite system development. This paper focuses on power-domain non-orthogonal multiple access (NOMA for simplicity), which has the potential to increase the number of access users and improve user communication capacity within the cognitive network. The integration of NOMA into CR networks holds immense potential for improving spectral efficiency and accommodating a larger user base. Notably, NOMA leverages successive interference cancellation (SIC) to decode information from the far user (FU) by the near user (NU), enabling the NU to potentially relay data and assist the FU. To fully harness this characteristic, we propose the utilization of cooperative NOMA (C-NOMA) to enhance system performance while ensuring the quality of service (QoS) for the FU. In evaluating the performance of the proposed system, we conduct an analysis of the outage probability and bit error rate (BER). This analysis provides valuable insights into the effectiveness of integrating CR and C-NOMA to enhance the reliability and quality of satellite communication.