Graceful degradation of magnetic recording channels

Coding techniques are shown to provide an effective means of controlling the effects of bandwidth and gain variation associated with space losses. The combination of a specific channel code and a suitable partial-response detection technique is proposed and studies for the purpose of obtaining enhanced robustness. The technique presented for encoding and decoding digital audio signals offers the advantage of a graceful degradation of the performance when the signal is recorded on a digital recorder with a wide range of bandwidths. This situation may arise, for example, when contact between head and medium is insufficient. The technique can also be used for digital video signals or any other information that might carry significance information