High-performance servo channel for nanometer head positioning in tape systems

In a tape system, the core of the reel-to-reel and track-following servomechanisms is the servo channel, which processes the servo signal read back by a servo reader reading a timing-based servo pattern. The servo channel estimates essential servo parameters, such as tape velocity, head lateral position and longitudinal tape position. The achievable precision of the various estimates determines how densely data can be placed on tape. In this paper, the architecture and the design of the building blocks of a novel high-performance synchronous servo channel are presented. Simulation and experimental results indicate that the proposed servo channel allows nanometer head positioning in tape systems.