Noise pulse counting in band limited transfer system - using automatically-varied measurement of sampling time to suppress multiple detections

摘要

An arrangement counting noise pulses in band-limited transfer systems employs a variable measurement inactive time to reduce multiple detections caused by noise pulse-induced damped oscillations. The measurement inactive time is automatically adjusted to its optimum value dependent on the channel characteristics, magnitude of the impulse being measured, and the adjusted measurement level. This is achieved without variation to the measured result time distribution. Two threshold switches in the noise impulse counter initiate the measurement inactive time when the damped oscillation voltage first exceeds both threshold voltages. The measurement inactive time is terminated when the lower threshold voltage is again exceeded by the damped oscillation voltage. The higher threshold voltage is variable to enable noise pulse selection sensitivity adjustment.