The use of advanced signal processing techniques is becoming increasingly important as a cost-effective means to achieve high storage density in data storage systems. The Principal Investigator's research on pragmatic sequence detection algorithms for magnetic data storage channels has resulted in the successful development of a computationally efficient detection algorithm, which achieves a near-optimum performance under modulation code constraints that are important in magnetic recording. In this project, the Principal Investigator addresses several important issues related to the application of the proposed detection algorithm to practical recording systems. These are the issues related to: 1) the inherent error propagation problem associated with the proposed detection scheme, 2) code and detector sensitivity against the types of disturbances often encountered in real magnetic recording channels, 3) different options available for hardware implementation, and 4) adaptive formulation of the algorithm and the development of an advanced timing recovery scheme necessary for time-varying channel environments. The goal of this project is to carefully examine these issues, determine favorable hardware design options under real time-varying channel environments and provide solutions whenever potential problems exist. Potential benefits and limitations of the proposed method in comparison with conventional approaches will be thoroughly understood. In addition to providing information that is directly related to hardware implementation, the results of the proposed research help us understand code and detector behaviors under different types of channel disturbances. This will provide a basis for pursuing the challenging problem of designing codes and detectors which are immune to a selected type of channel disturbance.
