Exploration of a distributed approach for simulating spectrum sensing in cognitive radio

Abstract

Motivated by the problem of multiple unlicensed cognitive radio users seek to access unused frequency channels licensed to the primary users in a wireless communication scenario, this paper presents a simulation environment that is able to simulate various effects of radio wave propagation and shadow fading in a software model. A cognitive radio designer's intent, knowledge about the critical issues and trade-offs underlying in a particular design are implicit in the simulations set up. However, this knowledge is tightly conjoined with specific features and a thorough simulation analysis is essential. Towards this, an algorithm was developed for performing this distributed sensing method between neighboring terminals in a network. VHF TV Broadcast FM Broadcast and GSM systems were investigated as possible candidates of primary users. It was found that a high degree of detection probability could be obtained for the TV and FM broadcast systems than for GSM systems under the same environmental parameters, largely due to the higher transmit powers involved in broadcast networks. The probability of false detection cannot be completely negated without risking an increase in the probability of non-detection of a present primary system. Hence a trade-off can be shown to exist between these two probabilities. It can be concluded that minimizing the possibility of interference to primary users should take priority in this scenario.