Patent ID: 6084535
Filing Date: 2000-07-04
Classification: G11B,H03M

Abstract:
An encoder for coding an input signal in a communications system having a precoder, a partial response channel, a detector, and a decoder, the coded input signal having a Hamming distance of at least two at the output of the precoder for enhanced channel performance and a predetermined minimum number of ones at the output of the partial response channel for providing clock information, the encoder comprising:a serial-to-parallel converter having an input and a plurality of outputs for converting a serial string into parallel bits, the input of the serial-to-parallel converter coupled to receive the input signal;a code generator having a plurality of inputs and outputs for producing a first code bit using the equation v.sub.6 =cs.sym.v.sub.1 .sym.v.sub.2 .sym.v.sub.5 .sym.v.sub.9 .sym.v.sub.10 .sym.v.sub.13 .sym.v.sub.14 .sym.v.sub.17 .sym.v.sub.18, and a second code bit having a value based on the number of binary ones present in the input signal, the inputs of the code generator coupled to at least one of the plurality of outputs of the serial-to-parallel converter; anda parallel-to-serial converter having a plurality of inputs and an output for generating a serial string from parallel bits, the plurality of inputs of the parallel-to-serial converter coupled to at least one of the plurality of outputs of the code generator.