Circuit and method for deriving the word timing of a pulse position modulated signal

摘要

A method of deriving the word timing or word boundaries of a PPM signal, without requiring a synchronizing marker to be added to the PPM signal, employs a bipolar evaluation signal which begins at any time slot of the PPM signal. The evaluation signal is multiplied repeatedly with successive portions of the PPM signal within a time frame of the PPM signal which extends over a plurality of word lengths, and the product signals are integrated. Such repeated multiplications with subsequent integration are performed a number of times, with the evaluation signal being offset by one time slot each time. The time position of the evaluation signal which, after repeated multiplication and integration, produces the smallest possible signal, is considered to be in phase synchronism with the word timing of the PPM signal.