Proportional–Integral Synchronization for Nonidentical Wireless Packet-Coupled Oscillators With Delays

Precise timing among wireless sensor nodes is a key enabling technology for time-sensitive industrial networks (WSNs). However, the accuracy of degraded by manufacturing tolerance, aging crystal oscillators, and communication delays. This article develops framework packet-coupled oscillators (PkCOs) to characterize dynamics time synchronization clocks in WSNs. The nonidentical clock derived describe embedded clock's behavior accurately. A proportional-integral (PI) packet coupling scheme proposed synchronizing networked clocks, while, scheduling Sync packets different slots transmission. It also possesses feature automatically eliminating effects unknown processing delay, which further improves performance. rigorous theoretical analysis PI-based PkCOs presented via studying closed-loop system. performance evaluated on hardware testbed IEEE 802.15.4 WSN. experimental results show that precision protocol as high 60 μs (i.e., 2 ticks) 32.768 kHz oscillator-based clocks.