PURPOSE: To obtain a code converter with less redundancy by assigning a generation code of an even number bit having less code word disparity sum to an information source code having high frequency in use.
CONSTITUTION: A channel coder 4 is formed with an 8-8 code converting circuit converting an output of an A/D converter, a sample inverting/non-inverting device 6 to which an output of the converting circuit 5 is applied and a control circuit 7. A code with good DC balance and less code word disparity sum is assigned to an information source code generated with comparatively high probability, in the bit pattern conversion where the generation code in 8-bit is assigned by 1:1 correspondence to the information source code in 8-bit in the 8-8 code converting circuit 5. Further, the sample inverting circuit 6 conducts sample inversion such as +-+--+-+ (where + is non-inversion and - is inversion) by taking 8-sample as one period.
SUMA TETSUROU
ABE TAKAO
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