公开(公告)号：DE2557090A1

公开(公告)日：1976-08-19

申请号：DE2557090

申请日：1975-12-18

Applicant: IBM

Inventor： DENT III ROY FOGEL ,  SCHNEIDER RICHARD CRANE

IPC: H03M7/00 ,  G11B20/10 ,  G11B20/14 ,  H04L25/497 ,  G11B5/09 ,  G11B5/47

Abstract: Data signals are linearly recorded on a record medium as a sequence of discrete amplitude levels, each level occurring in a bit period. For each received data bit signal, a separate sequence of such levels is generated in accordance with a predetermined rule such that each separate sequence of levels extends over a predetermined number of data bit periods. All of the amplitude levels from a plurality of data bit signals occurring in each data bit period are summed together to provide a resultant amplitude to be recorded. Such resultant amplitude in each data bit period is linearly recorded on the record medium. Readback and detection of such recorded signals is accomplished by first recovering data bit signals by supplying the readback signals through a filter matched to the sequence (preferably a tapped delay line) for reconstituting the data bit signals. The reconstituted data bit signals are then detected using known data bit detection techniques. The techniques are also applicable to other types of digital channels.