Abstract: A multibeam antenna, which has a high switching capability with high RF power levels, consisting of three subarrays (5,6,7) which suitably spaced, assure angular coverage in the azimuth hemispace from 0.degree. to 180.degree.. A single beam forming network (2, 3) provides each subarray with the correct field amplitude and phase distribution. Switching is performed electronically.

Abstract: A horizon sensor for spaced-based satellites consisting of a high critical temperature superconductor which changes temperature based upon its exposure to space-based radiation. The horizon sensor may be flexibly positioned along the outer surface of the space- based satellite. As the orientation in space of the satellite varies, certain portions of the satellite body will be alternately exposed to radiation while other portions of the satellite body will be shadowed from it. As the sensor is exposed to radiation due to the change in orientation of the satellite body, the temperature of the superconductor changes due to radiation absorption. This change in temperature causes the conductivity of the superconductor within the sensor to vary, and this causes a change in voltage within the sensor. This voltage may be appropriately processed via land based or satellite based control systems to accurately measure and/or change the orientation of the satellite in space.

Abstract: A lightweight mechanical structure is provided for supporting an RF partitioning network for a large dimension array antenna. The network consists of two horizontally disposed stripline RF dividing circuits positioned in two enclosed portions of the network. The network is formed within an enclosure which is made up of rigid side frames and electrically conductive ground planes between which the microwave stripline dividing circuit is formed. The ground plates of the stripline circuit are bonded to rigid honeycomb materials so as to provide structural support. The network is assembled by means of suitable structural adhesives. The structure of the partitioning network of the present invention provides for the RF feeding and mechanical support of large dimension array antennae in one assembly.

Abstract: A device for processing radar signals has the capability of obtaining single or multiple target information as well as target length by utilizing relative radar-target movement. The device includes a radar receiver; an Inverse Synthetic Aperture Radar processor; a list sensor for supplying listing data to the Inverse Synthetic Aperture Radar (ISAR); an element for determining the presence of one or more targets as well as target length; a radar tracking loop for estimating parameters of target motion; and a display unit for displaying the processed information.

Abstract: A circuit for the regeneration of the clock signal within a message containing a preamble and random data. No assumption as to the message structure is required for the operation of such a circuit. The circuit operates on an autocorrelation principle which allows a voltage controlled oscillator (VCO) which is used to reconstruct the clock signal to operate free of the data format. The device is essentially formed as a phase correlator connected to a feedback loop which contains in series a filter, an amplifier and a voltage controlled oscillator. The correlator is formed by a delay line feeding a delayed data signal to two multipliers. The data is also fed to a shift register, the output of which is also fed to the multipliers. The multiplier outputs are fed to a differentiating element which outputs an error signal which acts as a clock correction signal feeding the VCO which, when necessary, adjusts the VCO output so as to match the clocking within the circuit with the clock timing of the message received.

Abstract: A device for automatic correction of differential and deterministic errors in a radar receiver, preferably a monopulse radar receiver, which comprises a closed loop feedback system in which raw Off-Boresight Angle (OBA) data as well as current azimuth data are accumulated, averaged and linearized through linear aggression techniques. This linearized data is combined with data relating to pre-calibrated known antenna parameters. This combined data is fed back and combined with the raw OBA signal to produce a correction OBA signal. The corrected OBA signal is algebraically summed with the current known azimuth data produced by the radar receiver to produce a highly reliable error corrected instantaneous OBA value.

Abstract: A process for the manufacture of ceramic materials by production of the citrates and pyrolysis thereof. Specifically, the process yields ultra-fine powders by preparing solutions of respective oxides and/or carbonates in nitric acid, either separately or together; adding citric acid to the solution to obtain metal-organic precipitates and neutralizing the solution with ammonium hydroxide. The neutralized solution is then heated to a temperature so that self-ignition occurs resulting in the production of the ceramic magnetic material as a homogeneous ultra-fine powder.

Abstract: An element with periodic structure for guiding electromagnetic waves propagating along a longitudinal axis of the structure at a speed below the velocity of light is disclosed. The structure includes a series of metal polar expansions aligned with the mentioned axis and forming a plurality of resonant metal cavities. The polar expansions have respective apertures aligned with each other so as to form a freeway for electron flow. First and second conductors are provided for cooperating with the polar expansions. The polar expansions each further respectively have first and second apertures for receiving first and second conductors that are preferably positioned diametrically opposed to each other with respect to the mentioned longitudinal axis.

Abstract: Recursive system for the forming of a radar image by means of a SAR sensor, for application preferably related to the radar field, essentially having a monodimensional transformation system (1) of the signal received by the radar; a convolution element (2) of the same signal by means of a monodimensional inverse transformation (3). The result of the convolution is retro-projected by means of element (4). In turn, the result of this operation, envelope-detected (5), provides an estimate of the electromagnetic characteristics of the teledetected scene. The invention belongs to the radar application field, and more precisely to that of synthetic aperture radars for teledetection. It finds its best application in the area of synthetic aperture radar signal processing.

Abstract: Lithium niobate is Li.sup.+ /H.sup.+ proton exchange in two stages. The first masked stage is a treatment with benzoic acid followed by a thermal treatment in oxygen at about 400.degree. C. The thermal treatment is followed by masking a second coincident area and treating that area in a second Li.sup.+ /H.sup.+ proton exchange with benzoic acid and lithium benzoate without altering the refractive index of the region outside the second area.

Abstract: A housing and connection device for electronic modules consisting of two parts, one of which is fixed and the other of which is movable. The movable part is detachably connected to the fixed part via a hook and pivot, and screw. The inside of the movable part contains a series of parallel grooves suitable for holding one or more electronic modules, such as printed circuit boards. The modules make electrical contact with a first motherboard at the rear of the movable part. The first motherboard in turn makes electrical contact with a second motherboard in the movable part, located above the first motherboard. The movable part also has a removable, grilled cover with a lock and it has an expansion system to accommodate additional modules.

Abstract: Device for angle measurement for inclusion within a monopulse amplitude comparison radar receiver for particular application within secondary radars. In essence it consists of a log (.SIGMA.) signal comparator (9) against a detection threshold, which is meant to enable further processing; of two-analog-numerical converters (10, 11), a codes (12), receiving outputs .SIGMA. and .DELTA. from converters above, which provides the calculation of target azimuth.

Abstract: A method of making symmetrical mercury cadmium telluride layers by epitaxial growth on a cadmium telluride substrate, performed inside a reactor with two communicating zones, kept at different and controlled temperatures. Growth solution is directly prepared inside the reactor by submitting to a specific thermal cycle a weighed tellurium quantity, a saturating cadmium telluride substrate and a mercury bath.

Abstract: Device for radar utilized to detect multiple-time-around echoes with the capability of transmitting in frequency agility and, besides the advantages due to this type of technique, further, capable of reading the ambiguity of distance directly by separating in frequency the multiple-time-around echoes. The device described is applicable to any pulses radar, such as for example, search or tracking, in which it is necessary to detect targets and recognize multiple-time-around echoes. Nevertheless its application is especially suited to a multifunctional radar (with phased-array antenna and monopulse capability).

Abstract: A process for making single-crystal mercury cadmium telluride layers by epitaxial growth on a cadmium telluride substrate, performed inside a reactor with two communication zones, kept at different and controlled temperatures. The growth solution is directly prepared inside the reactor by subjecting weighed cadmium and tellurium quantities and a mercury bath to a specific thermal cycle so that the mercury concentration in the solution is established by absorption from the vapor phase and is controlled by the lower temperature level.

Abstract: This invention concerns a synthetic aperture radar system within which focussing processing is achieved through the use of filter banks, based upon undersampling and polyphase networks. The focussing operation consists of the correlation of the datum with system response to a point scatterer.

Abstract: A method of making semiconductive developments, especially MESFETs, which applies a template to a surface of the substrate previously formed with circuit elements in alignment with these elements and so bonds the template to the substrate that the template can be utilized as a holder for the substrate. The rear surface is then coated with a resist and a second template aligned externally with the first utilizing markings exterior to the substrate to form the structure on the rear surface which can include throughholes for a metal deposit extending through the preferably GaAs substrate.

Abstract: Voltage regulator which can compensate for the output voltage variation of a line modulator for use in transmitters for radar applications. The voltage variation in question is due to the modulation induced by the radar repetition frequency. This regulator is essentially made up of a network (1,2,3,4,5,6,7) which varies the value of the input signal to a comparator 8 in relation to a signal which is proportional to the variation of repetition frequency.

Abstract: A digital processor for radar signals which can perform adaptive suppression of the disturbance clutter and enhancement of the useful signal of given Doppler frequency. It can approximate the principle of operation of the optimum processor, which is that processor which maximizes the signal-to-noise ratio. Such processor can also cancel, in a adaptive manner, a clutter component having an approximately Gaussian power spectrum.

Abstract: An electronic device for rapidly tuning a voltage controlled oscillator to the radar carrier frequency of each of the individual radar pulses. A frequency discriminator (1) of the quadricorrelator type is supplied with the incoming pulses and with the output of the VCO (5) to provide the control voltage to the VCO (5) via amplifying stages (2), (4) and a sample-and-hold circuit (3) that maintains the tuned frequency for time durations greater than 100 usec. The operating frequency range of the device is between 6GHz-18GHz.