OPTICAL DEVICE FOR TIMING RECOVERY OF CODE SIGNAL

摘要

PURPOSE: To recover the clock or timing of signals encoded along various digital codes by measuring part of the signals propagated in a feedback loop and making the measured part to correspond to a timing signal. CONSTITUTION: In order to permit the timing recovery of signals which can be encoded along a diversified digital codes, an encoded signal shaping circuit 1 is provided on the upstream of a timing recovering circuit 19 for shaping received encoded signals Si. The circuit 1 converts the signals Si into a pulse train Sf in which pulses have duration of half clock cycles T/2 in accordance with variable generation equal to N×T (where N represents an integer which changes as a function of digital codes used for encoding the signals). The first input 11a and first output 11c of the circuit 19 are respectively connected to the output Sf of the circuit 1 and the second input 11b of a feedback loop. Then part of the signals which are propagated in the feedback loop for being supplied to the second output 11d of the loop is measured with respect to the timing cycle and the part is made to correspond to a timing signal.