Abstract: An underwater maneuverable vehicle is presented which carries an explosive charge and can be used for immediate removal or destruction of various menaces to navigation and other underwater hazards. The battery powered vehicle is air dropped from a platform which carries an imaging lidar system for detection and is operated and navigationally controlled in conjunction with an imaging lidar system.

Abstract: An underwater maneuverable vehicle is presented which carries an explosive charge and can be used for immediate removal or destruction of various menaces to navigation and other underwater hazards. The battery powered vehicle is air dropped from a platform which carries an imaging lidar system for detection and is operated and navigationally controlled in conjunction with an imaging lidar system. In accordance with an important feature of this invention, an optical lidar downlink is used to control the submerged underwater maneuverable vehicle from an airborne platform. The downlink is pulse spaced modulated. Command signals are secure, and are decoded aboard the vehicle. Control in speed, heading and depth, as well as command detonation are available using this technique.

Abstract: A device automatically measures a distance relative to the longitudinal axis of a runway to be destroyed. This device comprises: a radar transmitter-receiver, at least one depointed antenna, distance-measuring gates, a threshold circuit and a computer circuit.

Abstract: A method and device for bandpass filter demodulation for FM-CW systems which includes providing a FM-CW signal to an input of a bandpass demodulator, amplifying the FM-CW signal, timing the bandpass demodulator at an integer multiple of the FM-CW signal frequency, and simultaneously demodulating/filtering the FM-CW signal to produce a signal in baseband containing suppressed carrier-Doppler sideband information from the FM-CW signal. The demodulating/filtering functions are performed in an appropriately biased and clocked switched capacitive filter.

Abstract: A spark gap transmitter mounted in the base plug of a projectile and powdd by the piezoelectric effect of ferroelectric crystals deformed upon projectile impact. The transmitter emits an RF pulse train in the S-band which may be detected by appropriate equipment which compares the impact point with the target location for aim point correction purposes.

Abstract: The invention relates to a radioaltimeter type detector comprising an oscillator-transmitter (10), a modulator (20) suitable for frequency modulating the oscillator-transmitter according to a given characteristic, a mixer receiving the signal from the oscillator-transmitter and a corresponding echo signal reflected by a target, and a discriminator circuit (50, 60) connected to the output from the mixer. According to the invention, the modulator (20) includes a digital memory (21) containing a series of values defining the frequency modulation characteristic of the oscillator-transmitter (10).

Abstract: An electronic proximity fuse of the FM radar type having a detonating circuit with two inputs. One input is derived from a signal representing the amount by which the frequency of the received signal differs from the frequency of the transmitted signal at the instant of reception averaged over the frequency-modulation period. The second input is derived from a signal proportional to the amount of the frequency fluctuations of the frequency deviation about the averaged amount.

Abstract: A radar apparatus transmits a pulse and receives a corresponding return within the duration of the transmitted pulse. The returned pulse and a proportion of the energy of the transmitted pulse are mixed in a mixer to produce a demodulated pulse of duration equal to the overlap in time of the transmitted and received pulses. In order to render the apparatus insensitive to close targets a video gate prevents the portion of the demodulated pulse corresponding to e.g. 0 to 1/4 full range passing to a processing circuit. The processing circuit forms the ratio of the amplitudes of two frequency components of the spectrum of the demodulated pulse as a measure of range (FIG. 3) or forms the mean amplitude of the demodulated pulse weighted according to a weighting function (FIG. 4).

Abstract: A proximity fuze system includes an optical ranging apparatus, a detonation circuit controlled by the optical ranging apparatus, and an explosive charge detonated by the detonation cirtcuit. The optical ranging apparatus includes a pulsed laser light source for generating target ranging light pulses and optical reference light pulses. A single lens directs ranging pulses to a target and collects reflected light from the target. An optical fiber bundle is used for delaying the optical reference pulses to correspond to a predetermined distance from the target. The optical ranging apparatus includes circuitry for providing a first signal depending upon the light pulses reflected from the target, a second signal depending upon the light pulses from the optical delay fiber bundle, and an output signal when the first and second signals coincide with each other. The output signal occurs when the distance from the target is equal to the predetermined distance form the target.

Abstract: Disclosed is a Doppler tracking processor and time of closest approach detector for use in active or semi-active radar-guided missiles. A known processor uses a fractional Doppler gate (FDG) to process the Doppler signal to activate the warhead detonation properly at time of closest approach (TCA); it indicates when the Doppler energy has rolled off to, for example, one-half the pre-intercept Doppler frequency. The present invention uses a Doppler tracking processor and TCA detector. The tracking filter can extract the instantaneous value of the Doppler frequency even during roll-off. The system processes the Doppler from the pre-intercept frequency up to an appropriate fractional frequency occurring at TCA, at which time it provides a signal for use in warhead detonation.

Abstract: A carrier frequency is frequency modulated with a triangular wave and transmitted from a sensor to a target having relative motion to the sensor. The reflection from the target is received and mixed with a portion of the transmitted signal. At least two harmonics of the modulating frequency are filtered from the output of the mixer. Each harmonic is synchronously detected with an harmonic of the same frequency to obtain a doppler signal that is detected and fed to a comparator. Each harmonic, and its corresponding doppler envelope, amplitude peaks at a respective range to the target. When the doppler of one harmonic exceeds the doppler of another harmonic in amplitude, a predetermined range to the target is signaled by the comparator.

Abstract: A guided missile having a radar system which is utilized as a target seeker and tracking radar as long as it is capable of tracking the target through the encounter, after which, or at some set distance from the target, the radar and associated circuitry provides the optimum burst time.

Abstract: Disclosed is a Doppler tracking processor and time of closest approach detector for use in active or semiactive radar-guided missiles. A known processor uses a fractional Doppler gate (FDG) to process the Doppler signal to activate the warhead detonation properly at time of closest approach (TCA); it indicates when the Doppler energy has rolled off to, for example, one-half the pre-intercept Doppler frequency. The present invention uses a Doppler tracking processor and TCA detector. The tracking filter can extract the instantaneous value of the Doppler frequency even during rolloff. The system processes the Doppler from the preintercept frequency up to an appropriate fractional frequency occurring at TCA, at which time it provides a signal for use in warhead detonation.