Control Loop Aware LTE-V2X Semi-Persistent Scheduling for String Stable CACC

Abstract

An analytical method for computing the channel access delay budget between consecutive kinematic updates among a vehicle pair in a cooperative adaptive cruise control (CACC) enabled platoon under string stability conditions is presented. It is shown that even first-order approximations of the complex exponential delay term yield good numerical results. The method also indicates when communication in CACC is not required. The calculated channel access delay budget is used to obtain the semipersistent scheduling period for string stable CACC under LTE-V2X Mode 3 communication. Furthermore, an efficient semi-persistent scheduling algorithm capable of allocating heterogeneous periods and supporting multiple platoons is presented and validated with two examples.