A Geometric Analysis Method for Evaluation of Coexistence between DSRC and Wi-Fi at 5.9 GHz

TL;DR

This paper introduces a geometric analysis method and a new performance metric to evaluate the coexistence of DSRC and Wi-Fi at 5.9 GHz, focusing on broadcast performance for safety-critical vehicular applications.

Contribution

It proposes a novel geometric analysis approach and a new metric for accurately assessing broadcast-based DSRC performance in coexistence scenarios with Wi-Fi.

Findings

The new metric provides a more precise evaluation of DSRC broadcast performance.

Guidelines for selecting MAC parameters like IBI and CW are derived.

The method improves understanding of DSRC-Wi-Fi coexistence at 5.9 GHz.

Abstract

Co-channel coexistence between Dedicated Short-Range Communications (DSRC) and Wi-Fi needs thorough study. The reason is that although the 5.850-5.925 GHz (5.9 GHz) band has been reserved for DSRC so far, the U.S. government is moving swiftly on opening the band to be shared with Wi-Fi. However, most prior work lacks sufficient scientific rigor by relying on performance metrics such as packet delivery rate (PDR) and packet delay that cannot accurately measure performance of a vehicular network that primarily uses broadcast in dissemination of packets. Precise analysis of such broadcast operation is essential for rigorous investigation of DSRC-Wi-Fi coexistence because most safety-critical applications of DSRC operate based on broadcast. This paper proposes a new metric that can more accurately characterize the performance of a broadcast-based DSRC network. The new metric is used to (i) characterize coexistence of DSRC with IEEE 802.11ac-based Wi-Fi and (ii) suggest selection of key medium access control (MAC) parameters for DSRC: inter-broadcast interval (IBI) and contention window (CW).