# Interference Regime Enforcing Rate Maximization for Non-Orthogonal Multiple Access (NOMA)

## TL;DR

This paper introduces an interference regime enforcing power allocation scheme that maximizes the sum-rate in Gaussian interference channels, enabling effective NOMA through successive interference cancellation.

## Contribution

It proposes a novel interference regime enforcement method with a generalized iterative waterfilling algorithm for ergodic rate maximization in NOMA systems.

## Key findings

- Significant sum-rate improvement over traditional schemes.
- Effective creation of very strong interference for NOMA.
- Validation through comparison with existing power allocation methods.

## Abstract

An interference regime enforcing rate maximization scheme is proposed to maximize the achievable ergodic sum-rate of the parallel Gaussian interference channels by enforcing very strong interference at receivers through power allocation whenever strong interference is observed. Applying successive interference cancellation (SIC) at the receivers, very strong interference can be completely eliminated in this case that enables non-orthogonal multiple access (NOMA). An optimization problem is formulated for ergodic rate maximization, where the conditions for creating very strong interference are included as additional constraints. Then, a generalized iterative waterfilling algorithm is derived to solve this optimization problem. The resulting power allocation scheme is compared in terms of the sum-rate with two other schemes when the interference is treated as noise with optimal or sub-optimal power allocation. The results show that the interference regime enforcing scheme provides major improvement to the sum-rate of parallel Gaussian interference channels and enables NOMA.