Delay-Optimal Scheduling and Power Control for Instantaneous-Interference-Limited CRs

TL;DR

This paper develops a delay-optimal scheduling and power control policy for uplink cognitive radio systems with heterogeneous channels, ensuring delay guarantees for secondary users while protecting primary users from interference.

Contribution

It introduces a novel closed-form policy that optimally balances delay performance and interference constraints in heterogeneous cognitive radio networks.

Findings

The proposed policy outperforms existing methods in simulations.

Explicit delay expressions enable better system design.

The policy guarantees delay bounds for all secondary users.

Abstract

We study an uplink multi secondary user (SU) cognitive radio system suffering statistical heterogeneity among SUs' channels. This heterogeneity may result in differentiated delay performances to these SUs and result in harmful interference to the PU. We first derive an explicit closed-form expression for the average delay in terms of an arbitrary power-control policy. Then, we propose a delay-optimal closed-form scheduling and power-control policy that can provide the required average delay guarantees to all SUs besides protecting the PU from harmful interference. We support our findings by extensive system simulations and show that it outperforms existing policies substantially.