Subcarrier-Chunk Assignment With Power Allocation and Multiple-Rate Constraints for Downlink OFDMA

TL;DR

This paper proposes a novel subcarrier assignment and power allocation method for downlink OFDMA systems that maximizes user rates while satisfying proportional-rate constraints, demonstrating improved performance over existing schemes.

Contribution

It introduces a chunk-based subcarrier assignment and a low-complexity power allocation algorithm tailored for multi-rate constraints in downlink OFDMA.

Findings

Higher average minimum achievable rate than existing schemes

Maintains small deviation from rate constraints

Effective in both single-cell and multi-cell systems

Abstract

We consider downlink OFDMA in which users are imposed with different proportional-rate constraints, and a base station would like to maximise user rate over subcarrier assignment (SA) and power allocation (PA). To attain the objective, we propose a chunk-based SA and low-complexity PA algorithms. Numerical results show that the proposed SA and PA can provide higher average minimum achievable rate than the existing schemes while keeping the deviation from the rate constraint small for both single-cell and multi-cell systems with fractional frequency reuse.