Performance analysis of cognitive radio‐assisted clustering car‐following V2X communication system

Abstract

Summary In this paper, we study high spectrum efficiency transmission in vehicle to everything (V2X) system to allow the roadside unit (RSU) broadcasts its safety information to vehicles which belong to a dedicated group. However, low latency and high reliability are tightly required in related applications of V2X; we explore advantages of cognitive radio (CR) and non‐orthogonal multiple access (NOMA) to form system, namely, CR NOMA‐V2X. Such considered system provides transmissions from the RSU to vehicles with respect to lower access latency and to enhance the packet reception probability. In the proposed scheme, the vehicles need channel state information (CSI) for signal decoding order, but we face with imperfect CSI occurs in practical scenarios. To evaluate such degraded system performance of the involved CR NOMA‐V2X, we introduce the approximate closed‐form expressions of outage probability. Numerical results indicate the validness of our derivations.