Channel modeling and detector design for dynamic mode high density probe storage

Probe based data storage is a promising solution for satisfying the demand for ultra-high capacity storage devices. One of the main problems with probe storage devices is the wear of tip and media over the lifetime of the device. In this paper we present the dynamic mode operation of the cantilever probe that partially addresses the problems of media/tip wear. A communication system model which incorporates modeling of the cantilever interaction with media is proposed for the system. We demonstrate that by using a controllable canonical state space representation, the entire system can be visualized as a channel with a single input which is the tip-media interaction force. A hypothesis testing formulation for bit-by-bit detection is developed. We present three different classes of detectors for this hypothesis test. In particular, we consider two different cases where statistics on the tip-medium interaction are available and not available. Simulation results are presented for all these detectors and their relative merits are explored.