Eliminating Premature Termination in Multihop Rendezvous for Cognitive Radio-based Emergency Response Network

2026-05-21

AI Summary

This work addresses the premature termination problem in multihop rendezvous protocols caused by the N−1 termination condition, which compromises reliability in post-disaster emergency communications. To resolve this issue, the authors propose a robust rendezvous mechanism incorporating coordinate-assisted neighbor verification and an autonomous termination strategy, ensuring complete neighbor discovery and accurate topology construction prior to protocol termination. As the first study to identify and mitigate this specific limitation, the proposed approach is generic and readily adaptable to various multihop rendezvous protocols. Experimental results demonstrate that, under a challenging scenario with 20 nodes, 20 channels, and high primary user activity, the method achieves 100% accurate topology discovery and reduces rendezvous time by up to 76% compared to baseline protocols.

Abstract

In post-disaster environments, damaged communication infrastructure severely limits coordination among emergency response teams. Cognitive radio networks (CRNs) enable rapidly deployable communication by allowing nodes to opportunistically access available spectrum. However, existing multihop rendezvous protocols typically rely on N-1 termination conditions, which can lead to premature termination, resulting in incomplete neighbour discovery and invalid network topology formation. This work identifies this limitation as a previously overlooked issue in multihop rendezvous protocols. This paper proposes a Multihop Reliable Dual-Modular Clock Algorithm (MR-DMCA) that eliminates premature termination and ensures reliable network formation. The proposed protocol introduces a coordinate-assisted neighbour validation mechanism and an autonomous termination strategy that guarantees complete neighbour and topology discovery before protocol termination. Although implemented within MR-DMCA, the proposed validation and termination approach is applicable to a wider class of multihop rendezvous protocols. Extensive simulations demonstrate that, in a worst-case scalable scenario with 20 nodes and 20 channels under high primary radio activity (m=2), MR-DMCA achieves 100% accurate neighbour and topology discovery while reducing rendezvous time by up to 76%, 37%, and 17% compared with baseline protocols. The results highlight that addressing premature termination is critical for reliable multihop rendezvous in cognitive radiobased emergency communication networks.

Problem

• premature termination
• multihop rendezvous
• cognitive radio networks
• neighbor discovery
• network topology formation

Innovation

• premature termination
• multihop rendezvous
• cognitive radio networks
• neighbour validation
• autonomous termination