Electrical circuits for timing signals
First Claim
1. A missing pulse detector for determining the true termination time of a sequence of pulses in a signal of an assumed predetermined length having a rising edge and a trailing edge, which sequence may include pulses which do not reach a predetermined threshold, the detector including a counter connected to count pulses exceeding said threshold, up to a predetermined number, an oscillator for producing pulses at twice the frequency of the pulses in the signal and an enabling circuit for allowing pulses from the oscillator to pass to the counter only after the termination of a sequence of threshold exceeding pulses from the signal.
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Accused Products
Abstract
From a first aspect this invention provides a missing pulse detector for determining the true termination time of a sequence of pulses in a signal of an assumed predetermined length having a rising edge and a trailing edge which may include pulses which do not reach a predetermined threshold, the detector including a counter connected to count pulses exceeding said threshold, up to a predetermined number, an oscillator for producing pulses at twice the frequency of the pulses in the signal and an enabling circuit for allowing pulses from the oscillator to pass to the counter only after the termination of a sequence of threshold-exceeding pulses from the signal.
11 Citations
10 Claims
- 1. A missing pulse detector for determining the true termination time of a sequence of pulses in a signal of an assumed predetermined length having a rising edge and a trailing edge, which sequence may include pulses which do not reach a predetermined threshold, the detector including a counter connected to count pulses exceeding said threshold, up to a predetermined number, an oscillator for producing pulses at twice the frequency of the pulses in the signal and an enabling circuit for allowing pulses from the oscillator to pass to the counter only after the termination of a sequence of threshold exceeding pulses from the signal.
- 5. A reflected signal measuring circuit including a missing pulse detector for determining the true termination time of a sequence of pulses in a signal of an assumed predetermined length having a rising edge and a trailing edge, which sequence may include pulses which do not reach a predetermined threshold, the detector including a counter connected to count pulses exceeding said threshold, up to a predetermined number, an oscillator for producing pulses at twice the frequency of the pulses in the signal and an enabling circuit for allowing pulses from the oscillator to pass to the counter only after the termination of a sequence of threshold exceeding pulses from the signal, the measuring circuit also incorporating a circuit for transmitting a sequence of pulses and receiving any reflection of that sequence for supply to the missing pulse detector.
Specification