On adaptive speed design in optical disc servo systems

For CD-ROM or DVD-ROM servo system design, it is desired to maximize the average bit rate subject to the constraints imposed by the servo motor, control circuits, decoding electronics, and other limitation factors. The bit transfer, which is governed by the scanning of the disc and the design of the speed profile of the spindle motor, is thus of paramount importance. In this paper, the speed profile design is formulated as an optimization problem and four different speed profiles are designed to maximize the bit transfer rate while accounting for different control constraints. All the designs are verified using a CD-ROM experimental setup. The design/analysis results are closely matched with the experimental data.