This paper proposes a new method to estimate time delay of a random impulse sequence in a short time with high accuracy.
In the proposed method, a Reset-Set Flip-Flop is used to obtain the rectangular pulse sequences which are set by the impulses of original signal and reset by the ones of delayed signal. Then the time delay which is sufficiently smal than the mean interval between impulses of the signal is directly estimated by measuring the total width of rectangular pulses in the given short time.
However, if the time delay is not so small then the output rectangular pulses of the Flip-Flop are incorrectly reset by the impulses coming before the real delayed ones, hence the estimated time delay becomes smaller than the real one. In order to overcome this disadvantage we propose the employment of adaptive gate which prohibits the inpouring of the impulses coming before the real delayed ones into the Flip-Flop. By this means, the output rectangular pulses can be reset correctly and we can estimate the delay accurately up to any desired large range.
The validity of the presented processes are verified by computer simulations using the Poisson random impulse sequences.
This method is also applicable for continuous random signals if we transform them into the corresponding pulse sequences by using proper pre-processing. The results applied to the continuous signals which have been obtained from the actual instruments showed the usefulness of the proposed method. The result was as good as that of the second-order cross-correlation method.
抄録全体を表示