Secondary Resource Allocation for Opportunistic Spectrum Sharing with IR-HARQ based Primary Users

TL;DR

This paper develops a resource allocation strategy for secondary users in spectrum sharing, leveraging knowledge of primary IR-HARQ protocols to optimize throughput while respecting primary user constraints.

Contribution

It introduces a CMDP framework based on ACMI for secondary resource allocation in IR-HARQ primary systems, solved via a novel RVI algorithm.

Findings

Effective secondary resource allocation policy derived

Maximized secondary throughput with minimal impact on primary users

Validated approach through simulation results

Abstract

We propose to address the problem of a secondary resource allocation when a primary Incremental Redundancy Hybrid Automatic Repeat reQuest (IR-HARQ) protocol. The Secondary Users (SUs) intend to use their knowledge of the IR-HARQ protocol to maximize their long-term throughput under a constraint of minimal Primary Users (PUs) throughput. The ACcumulated Mutual Information (ACMI), required to model the primary IR-HARQ protocol, is used to define a Constrained Markov Decision Process (CMDP). The SUs resource allocation is then shown to be a solution of this CMDP. The allocation problem is then considered as an infinite dimensional space linear programming. Solving the dual of this linear programming is similar to solving an unconstrained MDP. A solution is finally given using the Relative Value Iteration (RVI) algorithm.