Threshold circuit
AssigneeAB Bofors
InventorKjell Arne Hakan Gustafson
Life of this patent
Estimating the term…
Abstract
A threshold circuit for signal receiving equipment, particularly optical signals travelling to or from a rapidly flying object comprises a threshold determining device having an input accepting signal and noise pulses and an output emitting transmitted pulses which correspond to the signal and noise pulses that pass the threshold unit. Control circuits determine the threshold that is employed in response to the received signal and noise pulses. If the received signal and noise pulses have a relatively low amplitude, a relatively low predetermined threshold is employed. If the received noise and/or signal pulses increase in amplitude for a sufficient length of time, the control circuits respond by raising the threshold.
Claims6
A threshold circuit for signal receiving equipment particularly suited for use in signalling to or from a rapidly flying object such as a missile or rocket having means for establishing a threshold with an input for receiving signal pulses and noise pulses and an output for emitting pulses corresponding to those pulses at said input which pass the threshold circuit, wherein the improvement comprises:
- first and second control means, responsive to said input pulses and noise pulses for generating a first or second threshold within first or second predetermined threshold ranges, said first control means producing a first threshold in response to a condition when said input signal pulses and noise pulses exceed a predetermined reference level for a predetermined period of time with a predetermined number of pulses per unit time, for limiting the number of noise pulses per unit time passing to said output, said second control means producing a second threshold in the absence of said condition, wherein said second threshold is lower than said first threshold.
Dependencies are inferred from the claim text.