In the CDR circuit of the PON system which does bursting data playback from pulse duration distortion self method of detection and the pulse duration distortion

摘要

PROBLEM TO BE SOLVED: To provide a PON system CDR circuit incorporating the functions to self-detect and self-correct the pulse width distortion of input data by a simple method.;SOLUTION: The method includes: means 8 in which an edge phase histogram for the result of input data edge phase detection in CDR function means is created; means 11-13 in which a frequency-divided clock edge phase is detected from the result obtained by sampling, with an m-phase clock generated from a system clock, the clock which is derived from N-phase clock generation in the CDR function means by frequency-dividing it down to a system clock speed level, and a clock histogram is thereby created; and detection means 9 in which an N-phase clock jitter amount is detected from the clock histogram, and only a jitter component superposed in the input data is extracted by subtracting the clock histogram from the edge phase histogram and, from the superposed jitter component, a peak differing from an ideal 1-bit pulse width of the input data is determined to be and detected as a pulse width distortion amount.;COPYRIGHT: (C)2013,JPO&INPIT