Randomized Power Transmission with Optimized Level Selection Probabilities in Uncoordinated Uplink NOMA

TL;DR

This paper proposes an optimization method for power level selection probabilities in uncoordinated uplink NOMA systems to improve error performance, applicable to various detection algorithms and power level sets.

Contribution

It introduces a novel probabilistic power level selection optimization framework for uncoordinated uplink NOMA, adaptable to different detection algorithms and power configurations.

Findings

Optimized power level probabilities reduce block and bit error rates.

The quadratic programming approach effectively handles two-user collisions.

Iterative solutions extend optimization to multiple-user collisions.

Abstract

We consider uncoordinated random uplink non-orthogonal multiple access (NOMA) systems using a set of predetermined power levels. We propose to optimize the probabilities of selection of power levels in order to minimize performance metrics as block error probability (BLEP) or bit error probability (BEP). When the multiuser detection algorithm at the BS treats at most two colliding users' packets, our optimization problem is a quadratic programming problem. For more colliding users' packets, we solve the problem iteratively. Our solution is original because it applies to any multiuser detection algorithm and any set of power levels.