Decentralized Channel Access for Wireless Control Systems∗

We consider a decentralized channel access mechanism for multiple sensors communicating over a shared wireless medium with corresponding actuators. Each sensor independently and iteratively adjusts the rate at which it accesses the channel, in response to packet collisions arising from simultaneous transmissions. We provide theoretical conditions under which the decentralized mechanism converges to an operating point where desired closed loop performance of all control loops is met. Control performance is abstracted as desired decrease rates of given Lyapunov functions for each loop, which translates to necessary packet success rates on each link. Numerical simulations of the proposed mechanism are presented.