Performance evaluation of a new coding scheme for the peak detecting magnetic recording channel

A code designed for the magnetic recording channel with peak detection is compared with the industry standard (1,7) code. The coding technique produces two different peaks in the readback waveform which differ in both amplitude and phase. The detector for the code must distinguish between two different types of peaks in addition to determining the existence of these peaks. Using a simple linear model, results indicate that the code outperforms a (1,7) coded system for density ratios above a certain critical value. For a Lorentzian transition response and for the measured transition responses from both helical scan tape recorder and a thin film disk system this critical density ratio is approximately 1.5