Abstract 1. An improved noise-modulated distance-measuring fuze comprising in combtion: an oscillator; a transmitting antenna coupled to said oscillator for radiating a signal towards a target; a modulator coupled to said oscillator to cause frequency modulation thereof, said modulator comprising a random noise generator, a band-pass shaper connected to the output of said noise generator for frequency shaping the random noise output thereof, a limiter coupled to said band-pass shaper for amplitude shaping the frequency-shaped noise output thereof, an integrator coupled to said limiter for integrating the frequency-shaped and amplitude-shaped output thereof, and means connecting the output of said integrator to said oscillator in such a manner as to frequency modulate said oscillator; a receiving antenna adapted to receive a portion of the signal radiated from said transmitting antenna after reflection from a target; mixer means for mixing the received signal from said receiving antenna with a local signal taken from said oscillator to produce a difference-frequency mixer output signal, said mixer output signal having a frequency spectrum peaked at a frequency greater than zero that decreases with decrease of fuze-to-target distance, the frequency at which the mixer output signal is peaked and the broadness of the spectrum in the vicinity thereof for a given fuze-to-target distance being dependent upon the characteristics of said band-pass shaper and said limiter; and means coupled to said mixer and responsive to the frequency at which said mixer output signal is peaked for functioning the fuze at a predetermined fuze-to-target distance.
An improved noise-modulated distance-measuring fuze comprising in combination: an oscillator; a transmitting antenna coupled to said oscillator for radiating a signal towards a target; a modulator coupled to said oscillator to cause frequency modulation thereof, said modulator comprising a random noise generator, a band-pass shaper connected to the output of said noise generator for frequency shaping the random noise output thereof, a limiter coupled to said band-pass shaper for amplitude shaping the frequency-shaped noise output thereof, an integrator coupled to said limiter for integrating the frequency-shaped and amplitude-shaped output thereof, and means connecting the output of said integrator to said oscillator in such a manner as to frequency modulate said oscillator; a receiving antenna adapted to receive a portion of the signal radiated from said transmitting antenna after reflection from a target; mixer means for mixing the received signal from said receiving antenna with a local signal taken from said oscillator to produce a difference-frequency mixer output signal, said mixer output signal having a frequency spectrum peaked at a frequency greater than zero that decreases with decrease of fuze-to-target distance, the frequency at which the mixer output signal is peaked and the broadness of the spectrum in the vicinity thereof for a given fuze-to-target distance being dependent upon the characteristics of said band-pass shaper and said limiter; and means coupled to said mixer and responsive to the frequency at which said mixer output signal is peaked for functioning the fuze at a predetermined fuze-to-target distance.
Claim 2
Dependent Claim
245 words
An improved noise-modulated distance-measuring fuze comprising in combination: an oscillator; a transmitting antenna coupled to said oscillator for radiating a signal towards a target; a modulator coupled to said oscillator to cause frequency modulation thereof, said modulator comprising a random noise generator, a band-pass shaper connected to the output of said noise generator for frequency shaping the random noise output thereof, a limiter coupled to said band-pass shaper for amplitude shaping the frequency-shaped noise output thereof, an integrator coupled to said limiter for integrating the frequency-shaped and amplitude-shaped output thereof, and means connecting the output of said integrator to said oscillator in such a manner as to frequency modulate said oscillator; a receiving antenna adapted to receive a portion of the signal radiated from said transmitting antenna after reflection from a target; mixer means for mixing the received signal from said receiving antenna with a local signal taken from said oscillator to produce a difference-frequency mixer output signal, said mixer output signal having a frequency spectrum peaked at a frequency greater than zero that decreases with decrease of fuze-to-target distance, the frequency at which the mixer output signal is peaked and the broadness of the spectrum in the vicinity thereof for a given fuze-to-target distance being dependent upon the characteristics of said band-pass shaper and said limiter; and means coupled to said mixer and responsive to the frequency at which said mixer output signal is peaked for functioning the fuze at a predetermined fuze-to-target distance.
Claim 3
Dependent Claim
121 words
The invention in accordance with claim 1 wherein said last mentioned means comprises: an amplifier coupled to said mixer for amplifying the difference-frequency signal output thereof, a discriminator responsive to the output of said amplifier for providing an output of one polarity when the mixer output signal spectrum is peaked above a predetermined frequency and of the opposite polarity when the mixer output signal spectrum is peaked below said predetermined frequency, means coupled to the output of said discriminator for producing a firing signal when the output of said discriminator passes through zero after first having attained a predetermined level other than zero, and a detonator adapted to be fixed to function said fuze when said discriminator produces said firing pulse.
Claim 4
Dependent Claim
32 words
The invention in accordance with claim 1 wherein said limiter is so constructed and arranged that its output voltage approaches a square wave shifting between equal and opposite values at irregular intervals.