Abstract: A crossed-field microwave power tube. Electrons are emitted from a tubular lectrode at ground potential. The electrons are accelerated by an electric field toward a high voltage anode located within the tubular electrode. A magnetic field is oriented along the axis of the tube; the magnetic field is perpendicular to the electric field. The electrons follow curved paths in the space between the tubular electrode and the anode, while producing electromagnetic radiation in a TEM mode. The TEM radiation is easily coupled from the tube.

Abstract: An electronic oscillator being operable to detect millimeter wave and infrared frequency output signals over the range of 1-1000 GHz consists of a semiconductor device having a structure comprised of a first planar doped barrier region separated from a second planar doped barrier region by a superlattice region. Upon the application of a uniform electric field, the first planar doped barrier region operates as a means for injecting electrons into the superlattice region which then traverse to the second planar doped barrier region which operates as means for receiving the electrons. During transit through the superlattice region, the electrons undergo an oscillatory motion thereby making possible the detection of signals whose frequency is a function of the applied voltage and the periodic spacing of the superlattice.

Abstract: A shaft position, direction and timing assembly for a stepper motor in an ectrically controlled printing system operating in an environment subjected to relatively strong vibrational and shock levels is disclosed. A cylindrical coding member having one or more photo-optical coding tracks located adjacent one edge is mounted on the stepper motor shaft by being held in position by an inner support cylinder and an outer retaining collar. These three elements are commonly fastened to the stepper motor shaft by a pair of mutually opposing set screws. Photo emitter and receptor elements contained in a bifurcated subassembly are located at the edge of the cylindrical coding so as to oppose a coding pattern formed on the coding tracks for generating an electrical signal in response to the coding pattern acting to pass or interrupt light energy transmitted from the emitter to the receptor elements.

Abstract: A magnetic device of permanent magnet materials for the control of linearly xtending annular cross-sectioned magnetic fields formed of two concentrically nesting magnetic tubular elements defining an annular space therebetween, and inner and outer cladding magnets radially disposed around the outer of said tubular elements and interiorly of the inner of said tubular elements, the cladding magnets being thicker at the end extremities and diminishing in thickness towards and to the plane of zero magnetic potential at or near the center line of the device measured along its longitudinal axis.

Abstract: The digital frequency divider (or synthesizer) produces non-integral submultiples of an input frequency by alternately dividing its input by two integers by means of two integral digital frequency dividers, one of which produces an output higher than the desired non-integral submultiple and the other of which produces an output lower than the desired non-integral submultiple. The desired non-integral submultiple is obtained by alternately switching the circuit output to two integral digital dividers, the duty cycle of the switch determines the precise output frequency obtained. The concept can be implemented with programmable digital counters and logic circuitry. The circuitry can be used to implement a novel method of duplicating an accurate signal with improved stability. A circuit useful in practicing the method measures the ratio of two frequencies.

Abstract: An audiographic telephone conferencing system between a plurality of parties or users either directly connected or through a piece of apparatus known as a "meet me bridge" over voice grade telephone lines. Each user has a programmed personal computer which controls a programmable or "smart" modem, cassette recorder/player, and speakerphone. A protocol is implemented by the software, i.e. the computer program, in each of the computers which puts its respective modem in a listening mode to monitor the phone line at all times. The computer is further programmed and includes a memory for storing and transmitting graphics presently on hand to other user(s) via the modem during a teleconference or alternatively receive graphics from another user, or it can switch to an external graphics program to make new or modify existing graphic images.

Abstract: A heterodyne CO.sub.2 optical Doppler radar comprising a ring type of traitter laser and twin local oscillator lasers which are automatically controlled to operate at a difference frequency equal to the intermediate frequency of the radar, which may be in the VHF band. The output of one of the twin lasers is injected into the transmitter laser for stabilization purposes and the output of the other of the twin lasers is heterodyned with the received target return signals to form the radar's intermediate frequency signal.

Abstract: A passive millimeter wave image guide power limiter comprising a length of ielectric transmission line or waveguide for millimeter wave frequencies located on a relatively thin conductive ground plane forming thereby an image guide and including a planar doped barrier diode structure formed in the dielectric transmission line with the planar doped barrier structure being integrally grown in a slot milled in the constituent material, i.e. gallium arsenide, of the waveguide transversely across the width dimension thereof so as to be oriented perpendicular to the flow of RF power being propagated along its length dimension. The planar doped barrier structure becomes conductive at a predetermined power level to reflect any further incident RF power back toward the power source.

Abstract: Selective etching of microelectronic devices comprising crystal substrates s achieved by electrically masking conductive areas thereon which are not to be etched by ionic bombardment. The electrical masking is accomplished by biasing the selected areas with a bias voltage which will repel the ions, which are attracted to all of the unbiased portions of the microelectronic device.

Abstract: A rare earth permanent magnetic apparatus for the containment and control thout any substantial loss of field flux comprising electro-deposited layers of rare earth magnetic material disposed and laid up around a ferrite center core element, the first or inner layer comprising a uniformly thick supply magnet to produce the magnetic field to be controlled, and the second or cladding magnet constituting a layer of diminishing thickness from the outboard ends of the device towards and to the plane of zero magnetic potential at or near the middle of the device.

Abstract: Steerable phased array antennas of the tapered type in which the antenna ment power is maximum at the center of the array and tapers off on either side thereof. The phase shifters of each antenna element are of the binary digital type with the number of stages and hence the phase accuracy being maximum for the high power center antenna elements and tapering off on either side thereof. Redundant stages for the binary phase shifters can be provided to increase reliability.

Abstract: Circuitry is disclosed for processing Doppler-shifted radar signals or ot noisy signals which fluctuate widely in frequency. The circuitry includes a dual channel discriminator including a voltage controlled oscillator as part of a feedback loop for frequency tracking of said signals. The discriminator further includes a frequency pass circuit in one channel thereof and a frequency stop circuit in the other channel thereof, with the outputs of these circuits applied to a multiplier. The multiplier output controls the frequency of the voltage controlled oscillator. The voltage controlled oscillator output is heterodyned with the input signals to obtain the heterodyned signals for application to the aforementioned two channels of the discriminator.

Abstract: A magnetic cladding device having a constant exterior magnetic potential al to a magnetic potential at a point between either end of an active magnet for enhancing the active magnet's field and reducing magnetic field leakage comprising a magnetic cladding circumscribing an active magnet and having a magnetic axis transverse to that of the active magnet.

Abstract: A phase transition detector for PSK signals which utilizes a dual channel SAW differential delay line to achieve a required delay. Each channel or path of the SAW device comprises an input and an output transducer. The two channels provide a predetermined differential delay (T) inasmuch as they are of different lengths. A PSK input signal is delivered to a power splitter, with the output therefrom coupled to the pair of input transducers of the SAW device. The output transducers are coupled to a multiplier which serves to detect phase transitions in the input PSK signal. The multiplier output is coupled to an output terminal via a low pass filter which provides harmonic repression. In another embodiment a SAW device comprises a bank of dual channel differential delay lines with each dual channel set to a different predetermined delay (T) so that a plurality of PSK signals of different chip rates can be separated out and detected.

Abstract: A millimeter wave dual beam line scanning antenna integral with a tunable solid state oscillator is disclosed. The antenna provides two fan-shaped beams from opposite faces and when the antenna is rotated, a roughly conical shaped scan obtains. Furthermore, variation of the oscillator frequency causes a variation in radiation angle and provides two line scanning beams from opposite faces.

Abstract: Acoustic signal processing apparatus for the frequency-partition processing f a wideband RF spectrum surface acoustic wave (SAW) input signal into a multiplicity of relatively narrowband individual contiguous acoustic wave output signals, utilizing a wideband, linearly-dispersive, slanted array input transducer arranged on a wave-conductive surface with multiple arrayed output transducers, each frequency-responsive to a respective band of frequencies emanated from the input transducer.

Abstract: A resonator having a desired frequency is made from a quartz crystal resonator plate by a method including the steps of:(A) etching the quartz crystal resonator plate to a frequency slightly higher than the desired frequency,(B) vacuum desposting metallic electrodes onto the active area of the resonator plate to lower the frequency to a frequency that very closely approaches the desired frequency, and(C) treating the plate with the deposited electrodes with UV-ozone to oxidize the electrodes in a slow, precisely controlled manner to the desired frequency.

Abstract: A relatively narrow beamwidth (10.degree. or less) receiving antenna patt is formed at the receiver end of a radio frequency transmission link where a plurality of radiating sources are operating in a dense communications environment. The antenna pattern comprises the difference between two antenna receiving patterns where the beamwidth of one pattern is wider by a predetermined angular amount than the other pattern. In the preferred embodiment, a phased linear array of antenna elements is operated as two sets of elements wherein one set of elements comprising a number of elements less than the total number of elements provides a beamwidth that is broadened by a predetermined angular sector greater than the beamwidth formed by the entire array. The antenna elements are progressively phase shifted to provide overlapping beam patterns and the pattern of one set of elements is scanned so that one side of both patterns are substantially coincident.

Abstract: A low level input pulse signal from T.sup.2 L logic is delivered to the it of a ground deck driver which is transformer-coupled to a floating deck driver. The leading edge of the input pulse serves to enable or trigger a first FET driver, which is coupled to the gates of a plurality of series-connected FETs via a first transmission line transformer. The triggering of the FET driver serves to turn-on the series-connected FETs so that the same delivers a high voltage signal to an output load. A second FET driver is coupled to the gates of another plurality of series-connected FETs, which serve as a "tail-biter" to terminate the power to the output load. And, a third FET driver is coupled to the gates of the first-mentioned series-connected FETs to turn the same to the OFF state. The second and third FET drivers are coupled to their respective series-connected FETs via respective transmission line transformers.

Abstract: An interference cancelling transmitter is configured which provides electagnetic compatibility (EMC) among different communications apparatus in the same area as well as providing a low probability of intercept (LPI) in a dense communications environment where secure communications is required between users. This is accomplished by means of a communications transmitter coupled to a transmitting antenna configuration comprised of an omnidirectional antenna and a notch antenna having a single deep null over a small angular beamwidth. RF power is fed equally thereto so that the radiated power from each antenna is the same but the phase is mutually inverted (180.degree.) so that a cancellation of the radiated power occurs in all directions of space except over the angular region where the null of the notch antenna is located. The null can be varied in direction and results in a relatively narrow pencil-like radiation pattern being radiated to a predetermined receiver.