A Reliable Self-Adaptive Scheduling Control Protocol for Cellular V2X Mode 4

Abstract

The rapid development and deployment of the Cellular V2X (C-V2X) require a highly reliable support system for many vehicular key applications. However, the current standard sensing-based semi-persistent scheduling (SB-SPS) protocol yields poor performance in terms of reliability, due to the hidden terminal problem and the half-duplex issue. In this paper, we propose a reliable self-adaptive MAC protocol for C-V2X Mode 4 (autonomous sidelink). It utilizes frame information and RSSI to exclusively scheduling resource blocks in two-hop neighbors, and dynamically adjusts scheduling and frame length according to changes of the network environment. Simulation results in show that the proposed protocol achieves significantly higher PDR than SB-SPS and IEEE 802.11p, while it only causes a relatively small number of the packet collisions.