Variable threshold signal detection system

Claim 1

AN ELECTRICAL CIRCUIT FOR IDENTIFYING THE OCCURRENCE OF LEGITIMATE SIGNALS OCCURRING WITH CONCOMITANT NOISE OF KNOWN CHARACTERISTICS AND FOR AUTOMATICALLY OPERATING TO PROVIDE A HIGH DETECTION PROBABILITY AND A LOW FALSE INDICATION RATE, THE CIRCUIT INCLUDING THE COMBINATON OF FIRST AND SECOND ADJUSTABLE THRESHOLD CIRCUITS COUPLED TO RECEIVE THE DESIRED SIGNALS AND CONCOMITANT NOISE AND TO PROVIDE OUTPUT SIGNAL INDICTIONS, A RESETTABLE COUNTER COUPLED TO THE SECOND ADJUSTABLE THRESHOLD CIRCUIT FOR COUNTING OUTPUT SIGNAL INDICATIONS PROVIDED THEREBY, MEANS COUPLED TO THE RESETTABLE COUNTER FOR RESETTING THE COUNTER AT INTERVALS, A SETTABLE REGISTER FOR PRESENTING A COUNT INDICATIVE OF A SELECTED FALSE INDICATION RATE, A COMPARATOR CIRCUIT COUPLED TO THE RESETTABLE COUTER AND THE SETTABLE REGISTER FOR PROVIDING SIGNALS INDICATIVE OF THE RELATIVE MAGNITUDES OF THE COUNTS PRESENTED BY THE RESETTABLE COUNTER AND SETTABLE REGISTER, AND MEANS COUPLED BETWEEN THE COMPARATOR CIRCUIT AND THE ADJUSTABLE THRESHOLD CIRCUITS FOR SETTING THE THRESHOLD LEVELS PROVIDED BY THE THRESHOLD CIRCUITS IN A PROPORTIONALITY DETERMINED BY THE CHARACTERISTICS OF THE NOISE, SUCH THAT THE SECOND THRESHOLD CIRCUIT PROVIDES OUTPUT SIGNAL INDICATIONS WITH A HIGH FALSE INDICATION RATE AND THE FIRST THRESHOLD CIRCUIT PROVIDES OUTPUT SIGNAL INDICATIONS WITH A HIGH DETECTION PROBABILITY AND LOW FALSE INDICATION RATE.