# Capacity Enhancement of Cooperative NOMA over Rician Fading Channels with Orbital Angular Momentum

## TL;DR

This paper introduces a novel cooperative NOMA scheme utilizing orbital angular momentum to significantly improve sum capacity in Rician fading channels, supported by analytical and simulation results.

## Contribution

It presents a new CNOMA-OAM scheme that enhances sum capacity over traditional schemes in Rician fading channels.

## Key findings

- CNOMA-OAM outperforms conventional CNOMA and OMA with OAM in sum capacity
- Power allocation for OAM beams significantly affects system performance
- Analytical results are validated by simulations showing capacity improvements

## Abstract

This letter proposes the usage of orbital angular momentum (OAM) for cooperative non-orthogonal multiple access (CNOMA) to enhance sum capacity (SC) for the future cellular communication system. The proposed CNOMA-OAM scheme is analyzed and compared with other schemes, i.e., conventional CNOMA, conventional orthogonal multiple access (OMA) with OAM. The impact of the power allocation factor for OAM beam over SC is also analyzed. The analytical result is justified by simulation results which demonstrate that the proposed CNOMA-OAM provides higher SC compared to other schemes.