Data modulation and transmission

摘要

In a data transmission or modulation system, a clock is reproduced stably. If data (limiting code) containing a plurality of consecutive minimum inversion interval Tmin is contained in the data inputted from a shift register, a Tmin consecution limiting code detection unit detects it. A constraint length judgement unit judges the constraint length i to be the constraint length corresponding to the code for limiting the constraint length i when a detection signal is inputted from the Tmin consecution limiting code detection unit, and outputs it to a multiplexer. The multiplexer selects the output of a converter corresponding to the constraint length supplied from the constraint length judgement unit out of converters 14-1 to 14-r, and outputs it to a run detection processing unit through a buffer. <IMAGE>