Abstract: A radar system has a transceiver and a ferroelectric phased array antenna. The antenna includes a plurality of radiating elements each connected to a ferroelectric phase shifter. The transceiver and the phase shifters are coupled for conveyance of radio frequency signals therebetween. A beam control computer calculates phase shifter control voltages which are applied to a beam correction computer. A temperature sensor is coupled to each phase shifter to provide feedback temperature values to the beam correction computer. A data table in the beam correction computer provides phase shifter correction voltages as a function of control voltage amplitudes and temperature values. The beam correction computer uses the data table in determining temperature corrected phase shifter control voltages which are applied to the associated phase shifters.

Abstract: A Doppler radar speed measuring module, that is self-contained and handheld, is fabricated on a multilayer PCB (printed circuit board) containing at least one antenna array and electronic circuitry. In one embodiment the antenna array is located on a top side and electronic circuitry is located on a bottom side opposite the antenna, with a ground plane layer sandwiched between the antenna array and the circuitry. The electronic circuitry includes a dielectric resonator stabilized oscillator, a microwave amplifier, a microwave mixer, a microwave coupler, voltage regulators, mechanical switches, and a display to indicate the measured speed of a moving target. The oscillator generates a very stable microwave signal which is split with part of the signal fed to a mixer and part fed to a transmit antenna. In one embodiment plated through vias electrically connect the two sides together. A transmitted signal reflects off of a moving target and is received by a receive antenna.

Abstract: An antenna system is described having a plurality of elements, one of which is an active element for transmitting or receiving signal, the remaining lements acting as reflectors, and wherein the elements may be comprised of a series of diodes connected in series with conductors having a length that is a fraction of the wavelength of the design frequency. When its diodes are biased for conduction, an element can radiate or receive r.f. signals or act as a reflector, and when its diodes are not conducting, the element is transparent to r.f. of the design frequency.

Abstract: An antenna array is described in which a feed line that is formed by metal atterns on opposite sides of a circuit board has a plurality of pairs of adjoining quarter wave resonant sections formed by different widths of the patterns and dipoles respectively coupled to the junctions of the pairs of quarter wave sections. The proximity between dipole elements and the feed line is sufficiently close to enable a nearly symmetric azimuthal antenna beam pattern. Each dipole further uses capacitive compensation at its center to balance the capacitive loading with the closely spaced feed line.

Abstract: Telecommunication systems and methods for driving a phased-array antenna ing a plurality of spaced antenna elements that radiate and receive a beam of radio frequency signals. Each of a plurality of ferroelectric phase shifters connect to a different one of the antenna elements. A signal processor system, having a receiver and a frequency synthesizer communicates with the phase shifters under the control of a data processor system. A joystick connects to the data processor system for permitting manual input of beam steering information thereto. The data processor system responds to the joystick inputs by controlling the relative phase shifts of the signals propagating in the ferroelectric phase shifters. The system further includes a temperature sensor circuit for sensing the temperature of each of the ferroelectric phase shifters.

Abstract: A voltage-variable ceramic capacitance device which has a plurality of las in a matching lattice structure and which possesses a symmetric voltage characteristic and a determinable voltage breakdown and has a high resistance to overbiasing or reverse biasing from an applied voltage. The device consists of a carrier substrate layer, a high temperature superconducting metallic layer deposited on the substrate, a thin film ferroelectric deposited on the metallic layer, and a plurality of metallic conductive means disposed on the thin film ferroelectric which are placed in electrical contact with RF transmission lines in tuning devices.

Abstract: A ferroelectric phase shifting antenna array consists of a plurality of lrally spaced antenna patches which have respective ferroelectric components abutting an edge of each patch at a near central location on the edge to provide impedance matching. DC control power lines are connected to the center voltage null position of the resonant mode of the antenna patch. An Rf source is connected to the other ends of the ferroelectric components through quarter wave coupled lines which provides simultaneous impedance matching and DC isolation.

Abstract: A heterostructure semiconductor device having source and drain electrodes sistively coupled to opposite ends of a channel, a barrier layer on one side of the channel, a delta doped layer in the channel or within a given distance of it, a gate electrode on the barrier so as to form a Schottky diode and at least one collector electrode mounted on said barrier layer. The collector electrode or electrodes can be resistively coupled to the barrier layer, but preferably the coupling is such as to form a Schottky diode. Changes to the gate bias affect the source current through the field effect mechanism. The collector current depends on the transfer of heated, energized carriers out of the channel over the front heterobarrier. At low gate bias, electrons entering the source travel to the drain while none travel to the collector. Energized carriers are localized to the depletion region due its high electric field drop.

Abstract: A phase shifter having a single or monolithic ferroelectric material and a lurality of ferroelectric transmission lines formed thereon, each having a different effective physical length and associated delay or phase shift. The plurality of different lengths of ferroelectric transmission lines has a voltage source associated therewith for applying a predetermined bias voltage, resulting in a change in permitivity in the ferroelectric substrate material. The different lengths of ferroelectric transmission line formed on the single substrate have a predetermined relationship between their effective physical linear lengths. By selectively activating the different lengths of ferroelectric transmission line by applying a bias voltage in different combinations, a desired or predetermined phase shift is obtained. The single or monolithic ferroelectric substrate used greatly reduces the overall length of the ferroelectric phase shifter.

Abstract: A system that provides an automated simultaneous measurement of the electal characteristics of a ferromagnetic material as a function of temperature and electric potential. The system utilizes a personal computer that interfaces with a DUT fixture through an interface measuring circuit that provides a means for remote control of the measurement process and insures a more timely and less manually intensive measuring process. The interface measuring circuit is composed of a temperature measuring circuit for measuring the temperature applied to the DUT, a capacitor measuring circuit for measuring the electric potential applied to the DUT, a high voltage power supply, a temperature plate power supply, a high voltage power supply driver, a digital voltage meter (DVM), and a DVM multiplexer. The system can utilize a humidity-free "dry" chamber (i.e. a desiccation chamber) to insure that the measurements of the DUT are reliable and accurate.

Abstract: A high voltage direct current power supply having feedback control and a tection circuit for maintaining a controlled, stabilized output voltage. An oscillator is coupled to a transformer which in turn is coupled to a voltage multiplier. A feedback control is coupled to the transformer and the voltage multiplier which provides feedback to the transformer for maintaining an accurate, stable output voltage. Coupled to the feedback control is a protection circuit which prevents the output voltage from exceeding a predetermined output voltage. Additionally, the protection circuit shuts down the power supply if a short circuit occurs at the output. In one embodiment, the voltage multiplier is comprised of a plurality of voltage doubler diode and capacitor pairs. The feedback control is comprised of a comparitor and a buffer which drives a transistor coupled to the primary of the transformer, which acts as a feedback loop. The protection circuit includes a J-K flip-flop.

Abstract: A ferroelectric phase shifter for shifting the phase of a radio frequency F) signal. The phase shifter includes a conductor line, a ground plane and a ferroelectric element between the conductor line and the ground plane to form a microstrip circuit through which the RF signal propagates. The ferroelectric element has a dielectric constant that can be varied as a function of a DC voltage applied to the ferroelectric element wherein the speed of the RF signal propagating through the ferroelectric element is a function of the dielectric constant. The phase shifter further includes a DC voltage source connected across the conductor line and the ground plane. The DC voltage source applies a variable DC voltage to the ferroelectric element in response to a control signal thereby to vary the dielectric constant of the ferroelectric element.

Abstract: A device for measuring the electrical characteristics of a ferromagnetic erial as a function of temperature, such as its dielectric constant verses temperature characteristics. The device having a quick mount fixture that utilizes a gravity feed and thermal grease to insure a quick reliable thermal connection between the temperature controller and the device under test (DUT). In addition, the device can be remotely controlled by a computer to automate the measuring procedure, thus reducing measuring time and alleviating the intensive manual procedure of making such measurements. Moreover, the device is easily mountable in a humidity-free or desiccation chamber to insure the measurements are reliable and accurate.

Abstract: A tetrahedral junction waveguide switch having a first length of hollow rangular waveguide and a second length of hollow rectangular waveguide adjacent each other with a ferrite rod longitudinally disposed therebetween. A magnetic field is created by a superconducting switching coil placed around the junction of the two lengths of waveguide. The normally magnetically biased ferrite rod permits electromagnetic wave energy to be transmitted through the first and second lengths of waveguide. An open circuit control means selectively and controllably interrupts the current flowing around the superconducting switching coil causing the longitudinal magnetic field to be removed from the normally magnetically biased ferrite rod. The waveguide switch is thereby placed in a cut off, nontransmission, or reflective mode preventing transmission of electromagnetic wave energy.

Abstract: A microwave oscillator capable of being switched into or out of the oscillating state within a fraction of the period of oscillation. The instant-on microwave oscillator permits both the generation and modulation of a microwave signal by using a single active microwave semiconductor device which is a resonant tunneling diode. The instant-on microwave oscillator circuit includes a conductive transmission line having an impedance Z.sub.O with a corresponding ground plane; and a pair of output terminals connected one on each of the transmission line and the ground plane. An impedance Z.sub.L, having an impedance value which is less than ZO, is positioned across the output terminals. A pair of input terminals is connected at the opposite end of the transmission line, one on each of the transmission line and the ground plane with a resonant tunneling diode connected across the input terminals. An impedance Z is connected to the input terminal on the biased side of the transmission line.

Abstract: A ferroelectric phase shifter, especially for the X-band, may be made from n elongated slab of ferroelectric material, which has a high dielectric constant that can be varied by applying an electric field. A narrow signal conductor is formed extending across a first surface of the slab, and a ground plane conductor is formed an opposite surface, forming a microstripline. An overall RF phase shifting circuit can be made by forming input and output circuits corresponding to the above-described signal conductor and interposing and connecting the signal conductor between the input and output circuits. The input and output circuits can be formed on respective, discrete substrates, with the ferroelectric slab being interposed between the substrates, or the input and output circuits can be formed on a common substrate, with the ferroelectric material inserted into a slot formed in the common substrate.

Abstract: The present Field Effect Real Space Transistor, or FERST, is a four terminal device with S, G, C, and D representing the source, gate, collector, and drain, respectively. The S, G, and D terminals can be likened to those of the MODFET. The collector name is borrowed from other real space transfer devices. Surrounding the entire device is an oxygen implant isolation. The source and drain ohmic contacts penetrate to the 150 .ANG. GaAs channel while the collector ohmic contact does not penetrate due to its position upon an elevated submesa. AlGaAs layers are used as etch stops during processing of the device and a Schottky barrier gate is placed on an undoped layer. Channel carriers are provided by modulation doping the lower barrier of the channel. An Al.sub.0.35 Ga.sub.0.65 As layer on the upper channel side is used as a real space transfer barrier. In operation and under appropriate bias conditions, real space transfer occurs across this upper barrier and into the collector.

Abstract: A circuit for measuring capacitor properties under high DC bias voltage. A apacitor is subject to a high DC bias by a high voltage supply having low AC impedance. A triangle wave voltage is applied to the capacitor at the terminal opposite the high bias voltage. A current is thereby induced due to the voltage difference across the capacitor generated by the triangle wave. The induced current is measured and properties of the capacitor calculated therefrom. The measuring circuitry is isolated from the high DC bias voltage applied to the capacitor. Therefore, the biasing voltage applied to the capacitor is limited only by the breakdown voltage of the capacitor under test.

Abstract: A planar stripline type of ferroelectric phase shifter which includes a set f series coupled phase shifter sections, each having mutually different and binary weighted lengths of ferroelectric phase shifting material. Fixed amplitude control voltages are respectively applied to one or more lengths of ferroelectric material the permittivity and effective electrical length of which change to provide a desired composite phase shift. The phase shifter, moreover, employs half wavelength spacings between elements or matching networks therebetween so that the microwave signal propagating through the phase shift will be minimally impeded between the input end and an output end.

Abstract: A device for radiating pulses of radio frequency energy in response to pulses of laser light in which a metal layer is ohmically bonded to one side of a substrate of semiconductor material and an antenna is ohmically bonded to the other side of the substrate, there being at least one aperture in the metal layer for permitting laser light to reach the disk.