Analysis of spectrum sensing in cognitive Internet-of-Vehicles with Mobile PUs and Mobile SUs

Abstract

Existing spectrum sensing algorithms in cognitive radio enabled Internet of Vehicles (IoV) consider primary and/or secondary vehicular user to be stationary. This assumption is unrealistic given that in many situations vehicular users are not stationary. This study developed an analytical model that incorporates the joint effect of the mobility of both Secondary User (SU) and Primary User (PU) where each vehicle is assumed to be mobile and equipped with a wireless device capable of communication and spectrum sensing. The study formally investigates the performance of the proposed approach for cognitive IoV using mathematical analysis. The effect of the SU sensing range, the relative velocity of the mobile SU and PU, the initial separation of the SU and PU on the probability of successfully sensing the PU and on the expected overlap time are investigated. The numerical results obtained from the derived models show that the probability of successfully sensing the PU increases with increase in the SU sensing range. It is further observed that the probability that the SU successfully senses the PU is lower when both SU and PU are mobile compared to the cases where the PU is fixed and the SU is mobile, and where both SU and PU are fixed. It is also noted that the probability that the SU successfully senses the PU decreases with increase in the relative velocity of the mobile SU and PU. The expected overlap time is observed to be higher when both SU and PU are mobile. The expected overlap time is further observed to increase with increase in the relative velocity of considers both mobile SU and mobile PU, it is limited to a situation where there is only one PU and one SU.