Experimental Demonstration of Delay-Bounded Wireless Network Based on Precise Time Synchronization

TL;DR

This paper experimentally demonstrates a delay-bounded wireless MAC protocol, CSMA/AP, using precise time synchronization via Wi-Wi, enabling collision-free, low-latency communication suitable for 5G and beyond applications.

Contribution

It provides the first experimental validation of CSMA/AP with real-time adaptation in wireless environments using software-defined radios and Wi-Wi synchronization.

Findings

CSMA/AP successfully operates in dynamic wireless environments.

Precise time synchronization via Wi-Wi is essential for CSMA/AP.

The protocol achieves collision-free, delay-bounded communication.

Abstract

Low latency and reliable information transfer are highly demanded in fifth generation (5G) and beyond 5G wireless communications. A novel delay-bounded wireless media access control (MAC) protocol called Carrier Sense Multiple Access with Arbitration Point (CSMA/AP) was established to strictly ensure the upper boundary of communication delay. CSMA/AP enables collision-free and delay-bounded communications with a simple arbitration mechanism exploiting the precise time synchronization achieved by Wireless Two-Way Interferometry (Wi-Wi). Experimental demonstration and proving the feasibility in wireless environments are among the most critical steps before any further discussion of CSMA/AP and extension to various applications can take in place. In this work described in this paper, we experimentally demonstrated the fundamental principles of CSMA/AP by constructing a star-topology wireless network using software-defined radio terminals combined with precise time synchronization devices. We show that CSMA/AP was successfully operated, even with dynamic changes of the spatial position of the terminal or the capability to accommodate mobility, thanks to the real-time adaption to the dynamically changing environment by Wi-Wi. We also experimentally confirmed that the proposed CSMA/AP principle cannot be executed without Wi-Wi, which validates the importance of precise time synchronization. This study paves the way toward realizing delay-bounded wireless communications for future low-latency and highly reliable critical applications.