IEEE 1588 style synchronization over wireless link

We present a technique for synchronizing clocks over a wireless link between a pair of resource constrained nodes. A Kalman filter is used as a pre-processor to a PI controller to mitigate the effects of packet-losses and attenuate noise spikes. This Kalman filter directly tracks the skew, which is the rate of change of offset, between a pair of nodes. The PI controller accepts this skew as input and disciplines the clock on the follower node. Experimental results demonstrate the performance of this technique over a single hop. In the future, this technique can be extended to multihop systems and improve determinism in networked embedded systems.

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