Cooperative Non-Orthogonal Multiple Access-Based Visible Light Communication Strategy for Power-Constrained Inter-Satellite Links

The role of inter-satellite communication (ISC) is of great significance in the contemporary era of satellite technology. In this context, visible light communication (VLC) has emerged as a highly promising alternative to conventional radio frequency (RF) communication. This is especially true for small satellites like CubeSats, where constraints related to size, weight, and power (SWaP) are of utmost importance. However, VLC systems' limited bandwidth makes it challenging to achieve large data rates and capacity. This can be evaded with the utilization of non-orthogonal multiple access (NOMA) as a fundamental technology to augment ISC based on VLC. Such schemes have already been evaluated and published in the public domain literature. There is, nevertheless, lack of information on the efficacy of utilizing cooperative NOMA (Co-NOMA) scheme in conjunction with VLC for a constellation of satellites, with limited power resources. This research study investigates the utilization of NOMA as the access technique for inter-satellite connections when communication is done through VLC under power restrictions, with a particular emphasis on reducing the bit error rate (BER) while enhancing the average sum rate (ASR) for distant satellites through Co-NOMA. The efficacy of the proposed methodology is verified through simulation results.