Abstract: A doppler radar system comprises a solid state microwave source which is pulsed on and off with a duty cycle typically around 10.sup.-3. The microwaves are transmitted towards a nearby target with a small amount supplied to a mixer also supplied with signals received from the target. The mixer output is passed through a gate opened in coincidence with the mixer pulsed output, and supplied to an integrator whose output forms a doppler signal representing target velocity. Target directionality is found by providing two channels fed in quadrature phase.

Abstract: In a digital scan converter for displaying video data provided by a radar sensor on a raster scan display, the video data is stored in a radar input buffer at addresses corresponding to the pattern according to which the field of view of the radar sensor is scanned, and taken over in a random-access memory. The random-access memory consists of N .times. N submemories, all containing a .times. a memory elements and all being simultaneously accessible. For the range scan in any azimuth value (.phi.) the range considered is divided into n (n.ltoreq.N) segments of each i k range increments .DELTA.r, where the length k.DELTA.r of each of said segments equals at least the range represented by "a" memory elements, multiplied by a factor .sqroot.2. An address generating circuit generates the addresses x = x.sub.c + (lk+m).DELTA.r cos .phi. and y = y.sub.c + (lk+m).DELTA.r sin .phi. where x.sub.c and y.sub. c represent the coordinates of the radar sensor position, l = 0, 1, 2, . . .

Abstract: A pulse radar distance measuring system in which the transmitter oscillator s injection-locked to a reference oscillator through a directional coupler. The pulses from the reference oscillator are of a duration which is approximately equal to the time required for the transmitted signal to travel to a target and return. The output of the transmitter oscillator is coupled to the transmitting antenna through the above mentioned directional coupler. The received target return signal is compared with the signal from the reference oscillator in a balanced mixer. The output of the mixer is coupled to a range-gated receiver and then to decision circuits for utilization.

Abstract: The invention includes an electron tube such as an image intensifier which utilizes a channel-type electron multiplier. The multipler is made of a perforated glass plate made in a manner such that secondary emission may be produced at the interior surfaces of the holes through the plate. Primary electrons are introduced to the holes at one end and a much larger emission emanates from the other end. Conductive layers on each side of the plate have holes in registration with the plate holes. The conductive layers are maintained at potentials to accelerate electron flow through the holes. In accordance with the present invention, a third conductive layer is provided at the output side. When the third conductive layer is maintained negative, resolution is improved.

Abstract: A system for jamming continuous wave radar type proximity fuzes used on surface-to-air missiles where the fuze requires an increase in return signal power level and a rapid frequency change for detonation. The system basically includes a receiver, amplifier, and transmitter. A received fuze signal is filtered and square wave modulated then sent to a first traveling wave tube for amplification. The signal is then amplified again by a second traveling wave tube which is modulated by a transit time modulator which continuously varies the phase shift through the tube in a linear fashion. The linear variation in phase shift is the equivalent of a displacement in the frequency signal being amplified. The signal is then reradiated to the missile giving the fuze a target sensing causing it to predetonate.

Abstract: A two dimensional velocity sensor mountable on an aircraft employs a CW radar which illuminates the ground with radar energy. Two transmitters which are alternately activated cause the speckle pattern to move as a whole in the opposite direction at the same speed. Two receivers mounted parallel to the heading axis of the aircraft sense the same power of the backscattered pattern except for a delay. By means of a time-shared processor and computer, this sensed delay provides heading velocity as well as cross-heading velocity.

Abstract: Two or more hydrogen thyratrons sequentially triggered with precision timing. The first tube is triggered and provides a long, low power, slowly rising pulse to a load. Approximately midway in said pulse the second tube is made to conduct, providing a short, high power pulse to the load. The second tube is triggered at a predetermined time delay after the first tube in response to the positive swing of the LC resonant circuit output.

Abstract: In a pulse radar apparatus the receiver is provided with a coherent side-lobe suppressing unit comprising:A. a first and a second transmission channel respectively for directional and omnidirectional reception of r.f. signals, each of said channels having a compression amplifier with the amplitude transfer characteristic y(t)={x(t)}.sup..alpha., where 0<.alpha.<1.B. a subtraction circuit and a phase and amplitude compensating network fed by the subtraction circuit and the second transmission channel to produce signals for the subtraction circuit, the latter signals being equal in phase and amplitude to the signals derived from the first transmission channel and applied to the subtraction circuit.

Abstract: A line sawtooth deflection current generator with modulating means for the purpose of correcting the amplitude variations of the current produced, the said modulating means including a stage operating in the switching mode, a switch of which is connected via a smoothing inductance. A winding coupled to an inductance in the deflection circuit is provided in the branch of the smoothing inductance between the scan capacitor and the switch.

Abstract: An FM/CW radar system with improved noise discrimination in which the received signal is multiplied by a sample of the transmitted signal, and the product signal is employed to deflect a laser beam as a function of frequency. The position of the beam is thus indicative of a discrete frequency, and it is detected by the frequency encoded positions of an array of photodiodes. The outputs of the photodiodes are scanned, then threshold detected, and used to obtain the range and velocity of a target.

Abstract: 1. A system for measuring the distance to a target comprising: means for nsmitting a signal to said target and for receiving a return signal from said target, means for mixing said transmitted signal and said return signal to produce a doppler signal, means connected to said mixing means and responsive to said doppler signal for initiating a first voltage timing function, means having a signal input connected to said mixing means and responsive to said doppler signal and a gating input responsive to said first timing function for initiating a second voltage timing function when said doppler signal reaches a predetermined value, and means connected to said means for initiating a second voltage timing function and responsive to said second timing function for producing a signal when said target is at a predetermined distance from said transmitting and receiving means.

Abstract: A radar which can be used in a system for identifying coded objects. A passive encoding array (label) for an object and having dipoles at selected dipole locations in the array, and a radar for scanning the array as it crosses the radar beam. The radar utilizes a doppler receiver and a matched filter processor to detect one of doppler, FM, and AM modulated FM signals from crossing targets. The radar output is a pulse code with pulses corresponding to the dipoles of arrays illuminated by the radar.

Abstract: Radar target back scattering is controlled by an impedance loading technique. The target is loaded with a variable impedance that is adjusted in response to the frequency of any incident radar signal to achieve optimum reflectivity for that particular frequency. Either radar target cross section reduction or enhancement is achieved over a broad band of frequencies by appropriate control of a voltage variable capacitance diode.

Abstract: A standard amplitude pulse is transmitted as a cyclically recurring pulse in a radar ranging system. At a receiver, identified by the pulse repetition rate of the recurring pulses, each pulse is analyzed for its deterioration from the standard in order to detect fading. An amplifier, having a controlled gain, is adjusted responsive to the analysis, and the uniformity is restored to the pulse despite variations in fading. In some cases, a threshold detection is used to prevent response to minor variations. A pulse repetition rate detector insures that the pulses are so controlled at only the identified station, and that the identified station responds only to pulses with the proper repetition rate.

Abstract: A pseudo-noise radar system in which a maximal length binary pulse code of amplitude zero or A amplitude modulates a carrier wave and reverses the phase thereof 180 degrees in synchronism. Either one of the amplitude modulated or phase reversed waves is transmitted. The received wave is then passed through a multiplicative mixer that receives the other wave as an input. The mixer output is then effectively (L + 1)/2 when correlated and effectively zero when phase shifted one bit to one bit less than a word, where L is the word length. Signals not correlated are thus attenuated to an extreme degree. The above-described pseudo-noise radar system may be used with any other conventional equipment for fire control, missile range and/or velocity tracking or otherwise.

Abstract: A beamformer for wideband signals wherein the elemental signals available the sensors of a receiving array are subjected to Fast Fourier Transformations which decompose them into a plurality of narrowband signals. The narrowband signals, which consist of signals having the same Fourier coefficients, are subjected to appropriate phase shifts to form a plurality of narrowband beams having the directional characteristics desired. Reconstruction of the wideband signal is accomplished by subjecting the narrowband beams to an inverse Fast Fourier Transform. The beamforming is thus performed with narrowband signals, and only phase shift circuits are required.

Abstract: A device for processing radar signals which enable precise Doppler information to be obtained. The signals, demodulated in cartesian coordinate X and Y and then coded are converted into polar coordinate .rho. and .theta.. Then .theta. is replaced by the difference .theta.' between two successive values of .theta. received during two consecutive repetitions. The couple .rho., .theta.' is converted into cartesian coordinate X' and Y', filtered and then reconverted into polar coordinate .rho." and .theta." where .rho." represents the amplitude relative to the echo and .theta." its Doppler speed.

Abstract: This invention relates to a method of separating pulses of a particular signal source from the total signal environment. A tracking gate technique is used in which guard bands are provided on ether side of the tracking gate. The guard bands detect interfering pulses before they coincide with the pulses being tracked. Upon detection of an interfering pulse the tracking system is switched from a leading edge tracking mode to a lagging edge tracking mode or vice-versa to prevent tracking gate "capture".

Abstract: An anti-missile missile employing an accelerator of the Van de Graaff or linear type which is carried by the missile to propel particles, such as gamma aluminum oxide, at hypervelocities, the particles being as small as about 10.sup.-7 cm in diameter.

Abstract: A clutter immune radar where the interrogating unit transmits a modulated interrogation signal to a remote unit, which radiates an information-bearing reply signal, in order to enable the interrogating unit to obtain remote unit information and range by the use of three bandpass filter channels where one bandpass filter bandwidth is equal to the sum of the other two bandwidths.