Cooperation and Underlay Mode Selection in Cognitive Radio Network

TL;DR

This paper introduces a hybrid spectrum sharing method in cognitive radio networks that allows secondary users to switch between underlay and cooperative modes based on primary link conditions, improving throughput.

Contribution

It proposes a novel hybrid spectrum sharing approach with adaptive mode selection based on primary link quality, enhancing secondary user throughput.

Findings

Significant throughput improvement over traditional schemes

Effective mode switching based on primary link state

Enhanced spectrum utilization and secondary user performance

Abstract

In this research, we proposes a new method for cooperation and underlay mode selection in cognitive radio networks. We characterize the maximum achievable throughput of our proposed method of hybrid spectrum sharing. Hybrid spectrum sharing is assumed where the Secondary User (SU) can access the Primary User (PU) channel in two modes, underlay mode or cooperative mode with admission control. In addition to access the channel in the overlay mode, secondary user is allowed to occupy the channel currently occupied by the primary user but with small transmission power. Adding the underlay access modes attains more opportunities to the secondary user to transmit data. It is proposed that the secondary user can only exploits the underlay access when the channel of the primary user direct link is good or predicted to be in non-outage state. Therefore, the secondary user could switch between underlay spectrum sharing and cooperation with the primary user. Hybrid access is regulated through monitoring the state of the primary link. By observing the simulation results, the proposed model attains noticeable improvement in the system performance in terms of maximum secondary user throughput than the conventional cooperation and non-cooperation schemes.