多通道交會問題（Multichannel Rendezvous Problem, MRP）是物聯網（IoT）應用中鄰居發現的一項重要挑戰，要求兩個用戶透過在可用通道之間隨時間跳頻來找到彼此。本文針對缺乏全域通道列舉系統的情境下的MRP進行研究。受到廣泛應用於數據中心和點對點網絡的一致性哈希（Consistent Hashing）的啟發，我們提出了低複雜度的區域性敏感哈希（LC-LSH）跳頻演算法。此外，我們不僅採用了增強多重集的模塊化時鐘演算法並提出了ASYM-LC-LSH4演算法，還將LC-LSH演算法與準隨機（Quasi-Random, QR）演算法結合，開發了QR-LC-LSH4演算法。該演算法保證最大交會時間（MTTR）有上限，同時實現低期望交會時間（ETTR）。大量模擬結果顯示，所提出的演算法即使在沒有全域通道列舉系統的情況下，在同步和非同步設定下，其性能仍可與最先進的LSH演算法相媲美。我們的研究為多樣化的物聯網環境提供了一種可靠的高效交會解決方案，並為未來在大規模、動態無線網絡中的研究與應用奠定了堅實的基礎。

The multichannel rendezvous problem (MRP) is a critical challenge for neighbor discovery in IoT applications, requiring two users to find each other by hopping among available channels over time. This paper addresses the MRP in scenarios where a global channel enumeration system is unavailable. Inspired by consistent hashing, which is widely used in data centers and peer-to-peer networks, we propose low-complexity, locality-sensitive hashing (LC-LSH) channel hopping algorithms. Furthermore, we not only employ the multiset-enhanced modular clock algorithm and propose the ASYM-LC-LSH4 algorithm but also integrate our LC-LSH algorithm with the quasi-random (QR) algorithm and develop the QR-LC-LSH4 algorithm to guarantee a bounded maximum time-to-rendezvous (MTTR) while achieving a low expected time-to-rendezvous (ETTR). Extensive simulations demonstrate that the proposed algorithms achieve performance comparable to state-of-the-art LSH algorithms in both synchronous and asynchronous settings, even in the absence of a global channel enumeration system. Our work provides a robust solution for efficient and effective rendezvous in diverse IoT environments, paving the way for future research and practical implementations in large-scale, dynamic wireless networks.

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