Optimization of azimuth angle and other geometrical parameters in digital tape recording

In guardband-less tape recorders, azimuth recording is commonly used to reduce intertrack interference. Previous work on the optimization of the azimuth angle for digital recording [1] uses the criterion of minimum on-track bit error rate (BER). In this article, we consider the maximum tracking margin to be a more relevant criterion. Furthermore, the calculation model in [1] is extended to cover a wider range of equalization and detection schemes, including the increasingly popular partial response Class IV equalization with Viterbi detector (VD). The gain of using VD over the conventional threshold detection is also discussed. BER measurements on several recorders with different geometrical configurations serve to verify the validity of the calculation results.<>