State Key Laboratory of Integrated Service Network, Xidian University, Xi'an 710071, China.
School of Telecommunications Engineering, Xidian University, Xi'an 710071, China.
Sensors (Basel). 2022 Jan 4;22(1):377. doi: 10.3390/s22010377.
Neighbor discovery is a fundamental function for sensor networking. Sensor nodes discover each other by sending and receiving beacons. Although many time-slotted neighbor discovery protocols (NDPs) have been proposed, the theoretical discovery latency is measured by the number of time slots rather than the unit of time. Generally, the actual discovery latency of a NDP is proportional to its theoretical discovery latency and slot length, and inversely proportional to the discovery probability. Therefore, it is desired to increase discovery probability while reducing slot length. This task, however, is challenging because the slot length and the discovery probability are two conflicting factors, and they mainly depend on the beaconing strategy used. In this paper, we propose a new beaconing strategy, called talk-listen-ack beaconing (TLA). We analyze the discovery probability of TLA by using a fine-grained slot model. Further, we also analyze the discovery probability of TLA that uses random backoff mechanism to avoid persistent collisions. Simulation and experimental results show that, compared with the 2-Beacon approach that has been widely used in time-slotted NDPs, TLA can achieve a high discovery probability even in a short time slot. TLA is a generic beaconing strategy that can be applied to different slotted NDPs to reduce their discovery latency.
邻居发现是传感器网络的基本功能。传感器节点通过发送和接收信标来发现彼此。虽然已经提出了许多时分邻居发现协议（NDP），但理论发现延迟是通过时隙数量而不是时间单位来衡量的。通常，NDP 的实际发现延迟与其理论发现延迟和时隙长度成正比，与发现概率成反比。因此，期望在减少时隙长度的同时提高发现概率。然而，这是一项具有挑战性的任务，因为时隙长度和发现概率是两个相互冲突的因素，并且它们主要取决于所使用的信标策略。在本文中，我们提出了一种新的信标策略，称为“听-说-应答”信标（TLA）。我们使用细粒度时隙模型来分析 TLA 的发现概率。此外，我们还分析了使用随机退避机制避免持续碰撞的 TLA 的发现概率。仿真和实验结果表明，与广泛应用于时分 NDP 的 2-信标方法相比，TLA 即使在短时隙内也能实现高发现概率。TLA 是一种通用的信标策略，可应用于不同的时隙 NDP 以减少其发现延迟。
