Multi-Objective Optimization of Joint Power and Admission Control in Cognitive Radio Networks Using Enhanced Swarm Intelligence

Ayman A El-Saleh,Tareq M Shami,Mohamad Y Alias,Rosdiadee Nordin,Ibraheem Shayea

doi:10.3390/electronics10020189

Abstract

The problem of joint power and admission control (JPAC) is a critical issue encountered in underlay cognitive radio networks (CRNs). Moving forward towards the realization of Fifth Generation (5G) and beyond, where optimization is envisioned to take place in multiple performance dimensions, it is crucially desirable to achieve high sum throughput with low power consumption. In this work, a multi-objective JPAC optimization problem that jointly maximizes the sum throughput and minimizes power consumption in underlay CRNs is formulated. An enhanced swarm intelligence algorithm has been developed by hybridizing two new enhanced Particle Swarm Optimization (PSO) variants, namely two-phase PSO (TPPSO) and diversity global position binary PSO (DGP-BPSO) variants employed to optimize the multi-objective JPAC problem. The performance of the enhanced swarm intelligence algorithm in terms of convergence speed and stability, while optimizing both the sum throughput and power consumption, is investigated under three different operational scenarios defined by their single objective priorities, which translate to sum throughput and power consumption preferences. Simulation results have proven the effectiveness of the enhanced swarm intelligence algorithm in achieving high sum throughput and low power consumption under the three operational scenarios when the network includes an arbitrary number of primary and secondary users. Comparing the hybrid SPSO approach and the proposed approach, the proposed scheme has shown its effectiveness in increasing the sum throughput to 7%, 16%, and 31% under the multimedia, balanced and power saving operational scenarios, respectively. In addition, the proposed approach is more power efficient as it can provide additional power savings of 3.58 W, 2.48 W, and 1.6741 W under the aforementioned operational scenarios, respectively.

Highlights

There has been a tremendous increase in the number of wireless devices such as smartphones, notepads and laptops
The Federal Communications Commission (FCC) conducted a study to figure out how the spectrum is being utilized and the results showed that the spectrum utilization varies temporally and geographically from 15% to 85% [1]
The performance of enhanced swarm intelligence of two-phase PSO (TPPSO) and DGP-BPSO is compared with hybrid combinations of the continuous Particle Swarm Optimization (PSO) variants listed in Table 3 and the binary PSO variants listed in Table 4 in terms of solution accuracy, convergence speed and stability

Summary

Introduction

There has been a tremendous increase in the number of wireless devices such as smartphones, notepads and laptops This makes spectrum scarcity the essential dilemma when launching new wireless services. Another fundamental issue that contributes negatively to the spectrum scarcity problem is the static spectrum allocation policy regulated by each and every national spectrum regulatory authority, such as the Federal Communications Commission (FCC) in the US, where a licensed user is assigned a fixed block of the spectrum on a long-term basis. This licensed user is typically known as a primary user (PU). The so-called television white space (TVWS) concept is seen as a key enabler for radio regulators to invest in such a secondary spectrum market [3,4,5]

Objectives

Results

Conclusion