Offset and Skew Estimation for Clock Synchronization in Molecular Communication Systems

Nanonetwork is a promising research field. It is composed of a number of nanoscale devices and is envisioned to apply to many potential applications. Clock synchronization is essential to establish a distributed cooperation among the nano-devices. This paper investigates the clock synchronization issue for the molecular communication system in the presence of Gaussian distributed propagation delay. A two-way message exchange mechanism is proposed. The closed-form expressions of maximum likelihood estimators for the clock offset and the clock skew are derived. Simulation results further demonstrate the effectiveness of the proposed estimators. This work lays a foundation for the complex cooperation of nanomachines in the nanonetworks.