Analytical model for predictable contact in intermittently connected cognitive radio ad hoc networks

Long Zhang,Chunhong Bai,Fan Zhuo,Haitao Xu

doi:10.1177/1550147716659426

Abstract

In this article, an analytical model for predictable contact between two cognitive users in the intermittently connected cognitive radio ad hoc networks is proposed. The salient feature of the model is that it establishes a relationship between contact availability and the intermittently connected cognitive radio ad hoc network design parameters including cognitive user transmission range, velocity of cognitive user, direction of cognitive user, velocity of primary user, direction of primary user, and interference radius of primary user. However, a detailed analytical model is not available in the literature up to now. In particular, the relationship between contact availability and interference radius of primary user has not been derived in previous models. To research the contact availability, the concept of contact degree is first proposed to quantify the probability of contact availability between two cognitive users. In addition, the formulation for the contact degree between two cognitive users from different cases is illustrated in detail in this article. Under the contact degree scenario, the continuous effective contact time is derived to examine the communication duration of cognitive users based on the modified random walk mobility model. Finally, the simulation results demonstrate the effectiveness of the proposed analytical model for predictable contact in the intermittently connected cognitive radio ad hoc networks.

Highlights

Cognitive radio (CR) or dynamic spectrum access[1] has newly emerged as a promising solution to improve the spectrum utilization by allowing unlicensed cognitive users (CUs) to access the idle licensed spectrum
In a cognitive radio ad hoc network (CRANET),[2] CUs can only access the spectrum opportunities (SOPs) in a distributed fashion by seeking to underlay, overlay, or interweave their signals with those of existing primary users (PUs) without significantly impacting their communications
The contact degree is first presented to research contact relationship between two CUs

Summary

Introduction

Cognitive radio (CR) or dynamic spectrum access[1] has newly emerged as a promising solution to improve the spectrum utilization by allowing unlicensed cognitive users (CUs) to access the idle licensed spectrum. Let CDm, n(t) denote the probability that CU m and CU n be in continuous effective contact at time instant t.

Results

Conclusion