Abstract: A system for transmitting and receiving very wide instantaneous bandwidth signals. Synchronized short pulse generators are positioned at the feed location of each element of a linear array of short capped monopole antennas to sequentially excite the antenna elements which are spaced in accordance with the sequential interval to provide a beam in the desired direction and space. Reflections of the radiated short pulses are received by a feed monopole backed by a reflecting monopole and coupled to a short pulse receiver through a duplexing switch.

Abstract: There is disclosed an acousto-optic filtering apparatus which includes Bragg cells in the signal path and in the local oscillator reference path of the apparatus in order to permit relatively high frequency signals to be detected by a relatively low frequency detector mechanism.

Abstract: A baseband receiver with a range gate interval in the order of nanoseconds. A tunnel diode, set to the low level state, is coupled across the output terminals of a bridge that is balanced in the absence of a received signal, during the range gate interval. Signals received by an antenna are coupled to a tunnel diode in an arm of the bridge causing it to change from its low level state to its high level state thereby unbalancing the bridge and establishing a voltage at the output terminals of the bridge that fires the tunnel diode coupled thereacross.

Abstract: Stabilization of the propagation of storage bits around the storage loops of a Vertical Bloch Line (VBL) memory is obtained by the vapor-deposition of a nickel-iron film over the VBL structure. The film has a composition range of 65-90% nickel and a thickness of 1,000 to 10,000 Angstroms, and is deposited in a vacuum of 10.sup.-4 to 10.sup.-6 Torr to provide parallel, periodic, magnetic stripe domains, and thus potential well domains, that have a periodicity in the range of 0.1 to 1 micron. The stripe domains are oriented perpendicular to the direction of data propagation and form potential wells along the elongated direction of the storage loops.

Abstract: A superconducting pin and socket conductor is formed with a cylindrical pin of superconducting material, such as niobium, which fits into a mating superconducting cylinder, such as niobium or titanium, which is open at the top. A superconducting wire is laser welded to the bottom of the cylinder and a second niobium wire is laser welded to the top of the pin. A sleeve of a material, such as copper, aluminum, or magnesium, which at liquid helium temperatures has a much higher coefficient thermal expansion than the superconducting material, surrounds the cylinder. As a result, upon cooling the outer sleeve crimps the cylinder into a firm and uniform contact along the length of the pin.

Abstract: An adaptive autopilot for Marine Vessles which seeks to obtain minimum combined hull and rudder drag while maintaining heading control by providing optimum rudder activity through a series of iterative steps.

Abstract: A synchronous clock circuit is provided on each module of an electronic digital system formed of a plurality of modules. Each clock circuit has two control pins which are used by control logic to determine whether or not the clock on a particular module is disabled, is operating as the master clock for the system, or is providing a backup function for the master clock. The common clock line is supplied through a buffer to the components on the module which require clocking. Logic circuitry on the backup clock mode insures the backup clock is in a ready condition in case there should be either failure of the master clock oscillator or if the master clock module is removed from the unit. All of the clock circuits of the different modules may be constructed in an identical manner, with the control of the function of the circuitry being provided simply by control of the logic level on the two terminals.

Abstract: Refresh signals for a multiple semiconductor MOS bank memory are implemented with a refresh counter that supplies 15.6 microseconds refresh pulses so that one row of 128 row of memory bank, or of each of a group of memory banks, may be refreshed on a sequential, stepped-through basis. The occurrence of each refresh pulse is effective to refresh one row or a group of rows, providing that refresh lock-out logic does not prevent the refresh pulses signals from being applied to the memory banks. An up/down counter is initially filled to a count of eight, and counts toward zero once each time a refresh pulse occurs and the memory is busy. As long as the count has not reached zero the lock-out logic is effective, but when a count of zero occurs refresh of each new row in the sequence occurs at the 15.6 microsecond rate until the memory is no longer busy; at which time a burst of eight count up pulses is supplied to the up/down counter, and eight new rows are rapidly refreshed at 450 nanosecond intervals.

Abstract: A SQUID, nominally of the "hybrid" type, wherein the normally superconducting modulation coil is modified to instead be a non-superconducting material, nominally manginin, exhibits reduced long-term, or d.c., thermal response. When an alternating current waveform--rising to a nominal 130 ma. r.m.s. amplitude within a nominal 0.5 seconds and, after a nominal 100 msec. to 20 sec. duration, returning to 0 within a nominal 0.1 sec--is applied to the non-superconducting modulation coil of such a SQUID at superconducting temperature then the entire SQUID thermal response, particularly including the short-term, or a.c., SQUID thermal response, is thereafter reducible to essentially 0. The process is hypothesized to "deflux" the SQUIDs of fluxons trapped during the cool-down of superconductor within the SQUID and associated circuitry. The optimal "de-fluxing" alternating current waveform for any individual SQUID is empirically derivable.

Abstract: A short pulse radar receiver having a detector with a threshold automatically adjustable with the level of noise and interfering signals. Interfering signals at signal levels which exceed the maximum for which a threshold may be achieved to prevent a false alarm are attenuated prior to coupling to the variable threshold detector by an attenuator variable automatically in accordance with the received signal level.

Abstract: A method and apparatus for detecting a short pulse signal in the presence of an interfering jamming signal wherein the jamming signal is utilized as the local oscillator in a diode mixer when it is received at a sufficiently high level for efficiently mixing with a short pulse signal. When the received jamming level is insufficient to act as a local oscillator, an internal local oscillator signal is coupled to the diode to maintain an efficient mixing operation.

Abstract: A method and apparatus for generating a bent sequence code as a transform of an m-sequence code.

Abstract: A high rate multiplexing system which is capable of operating on multiple channels while ensuring synchronization of the system operation. The system includes a basic timing network for synchronizing the system operation. Automatic phase adjusters are used to re-align data signals with a clock signal whenever data transitions occur while the data is being sampled. Synchronizing circuits are used to insert synchronization data bits into the multiplexed data streams where appropriate. A medium rate multiplexer generates two different data streams, certain clock signals and strobe signals. A higher rate multiplexer is capable of operation in different modes, including but not limited to wideband operation or narrow band operation. A Manchester encoder combines data output signals into a single aggregate data stream.

Abstract: A multiplexer system which operates as a standard multiplexer as well as a proportional multiplexer by providing typical multiplexing operation by one circuit portion and proportional multiplexing operation by other portions of the circuit wherein the multiplexer system can interface with a plurality of users or user devices in such a way that data streams between the user devices and the multiplexer system can be reallocated so as to enhance data transfer irrespective of the clock-to-data relationship such that no data is lost during circuit operation. The proportional MUX can be selectively controlled by a microprocessor.

Abstract: A digital power converter input current control circuit is connected between a power converter and a power source. This circuit monitors, and controls if necessary, the current that flows between the power source and the power converter in a manner that protects the power source, the input current control circuit, and the power converter from the catastrophic effects of excessive current flow. The input current control circuit operates similar to an electronic circuit breaker with an automatic reset feature, in that the power delivered to the power converter is maintained low during fault conditions. Thus, if a power transistor in the power converter should fail, a current limit circuit in the input current control circuit will prevent additional damage to the power converter.

Abstract: An electron beam magnetic deflection system capable of raster and stroke deflection and providing minimum power dissipation in raster mode. Automatic switching of the voltage demanded in raster mode is obtained by continuously sampling the yoke current, the power supply voltage being switched in magnitude and polarity corresponding to the direction of change and polarity of the yoke current. By returning energy stored in the yoke to the power supply during portions of the raster cycle, power efficiency is substantially enhanced.

Abstract: The use of a comparator and counter associated, on-chip, with each photo-element of an array. Sensing each photo-element without discharging it and allowing each photo-element to accumulate a charge which is large relative to noise variations. These features result in a photo-detector with large signal-to-noise ratios.

Abstract: An apparatus for applying convergence corrections to correct positional and misconvergence errors in a CRT employing a self-converging deflection yoke for magnetic deflection of an inline color gun assembly. Convergence correction coil windings are coupled to the deflection windings with the inductances and resistances of the convergence windings selected to match the time constants of the associated deflection windings. The applied deflection current signals are thereby apportioned between the deflection and convergence coils to modify the beam deflection and provide a beam deflecting flux proportional to the commanded deflection signals and a beam deflection center that is independent of the pattern written on the screen. The resulting currents in the deflection coils and convergence coils are a substantial replica of the commanded deflection current signal waveforms.

Abstract: An improved method for the automatic acceleration of an aircraft to a preselected speed is described. At any point in the climb portion of flight, a capture of a computed altitude that is increased at a specified rate is performed to provide optimal acceleration.

Abstract: A high frequency target seeking device, using a stabilized reflector antenna, performs range search and tracking functions and target angle search and tracking functions. A technique is provided for target range discrimination using several narrow band i.f. filters, also thereby improving signal-to-clutter ratio and signal-to-receiver noise ratio. Target search is accomplished with simultaneous range and antenna azimuth scanning, with the range bins and the antenna beam swept across the target. A multiplexer selects the range bin having signals indicative of the target. Target range tracking is accomplished by the multiplexer additionally automatically selecting range bins adjacent to the target's range bin and comparing their output signals. Antenna stabilization is accomplished utilizing signals from vehicle pitch, roll, and yaw rate sensors, and antenna elevation and azimuth rate and angle sensors.