Abstract: An apparatus for testing digital logic circuits without a computer and associated software employs a psuedorandom stream of input data to produce an unstructured output data stream which is analyzed by an efficient data collector and analyzer. Test signal generation is implemented by a pseudorandom number generator and a pseudorandom clock/reset generator while the resulting test data at the output terminals of the device under test is analyzed by a cycle redundancy code checker. Fault localization is realized, with selectable localization and manual probe modes and circuitry is provided for an efficient self-test mode.

Abstract: A surface wave transmission line enclosed in a dielectric shield and supported within the enclosure at a predetermined distance from the base of the enclosure. The enclosure being constructed such that the surface wave transmission line may be in close proximity to reflecting objects positioned along the enclosure and at a predetermined distance from a mounting structure.

Abstract: An antenna and a method for obtaining predetermined far field antenna patterns is disclosed. Empirical adjustments of a focal region feed system provides for the compensation of tolerance or other imperfections of the antenna to achieve the desired far field pattern. An element of the feed system is adjusted when the antenna is angularly positioned, with respect to a receiving element in the far field, which corresponds to the location of the element in the feed array. A desired far field pattern may also be achieved by illuminating the antenna aperture, either simultaneously or sequentially, by several plane waves, the amplitude and incident angles of which are carefully controlled, measuring the phase and amplitude of the focal region distribution caused by this illumination, and designing the feed system to establish a focal region distribution that is the complex conjugate of that measured.

Abstract: A feed system for scanning focal plane antenna systems with which a variable focal spot illumination may be achieved within the focal region of a primary antenna over a limited scanning sector is disclosed. An array of collector elements positioned to receive radiation from a scannable feed antenna is coupled to an array of radiator elements positioned in the focal region of the primary antenna, the positioning of the radiator and collector elements are such that the focal spot illumination is caused to vary with the scan angle of the antenna.

Abstract: An optical system is disclosed which, when utilized in conjunction with an electrographic printer and a laser light source, provides high quality characters at very high print speeds with a minimum of laser power. Horizontal and vertical light beam deflectors are employed to access a hologram in a two dimensional holographic array. The horizontal deflector is controlled by internally generated timing pulses to sequentially step from one column of the array to another, each column corresponding to a printing position on a line of print, while the vertical deflector is controlled by an external electrical signal to position a spatially unmodulated laser beam to illuminate the desired hologram in the column. The illuminated hologram emits a spatially modulated beam that forms an image along a line of print, at a position on a conductive drum corresponding to the column of the illuminated hologram.

Abstract: A collision avoidance system for rapid transit vehicles employing baseband radar principles in which signals with duration in the order of nanoseconds are transmitted down track along a surface wave transmission line. Reflections from a passive target located on the preceding vehicle are processed to establish the distance between the vehicles to within an accuracy previously unachievable.

Abstract: An analog signal multiplier has a pulse former which forms pulses with heights that are proportional to a first input signal and widths that are proportional to a second input signal, integrates the pulses so formed and at the conclusion of the integration, samples the integrated values and resets the integrator and pulse former.

Abstract: An apparatus which permits direct observation of an image produced by one image generator, simultaneously permits remote observation of an image produced by a second image generator, and switchably permits the simultaneous observation of both images directly and remotely.

Abstract: A radar system is disclosed which provides comprehensive radar elevation surveillance with a multiplicity of antennas, each of which supplies a fraction of the total elevation coverage. Each antenna provides a relatively narrow elevation radiation pattern which illuminates adjacent elevation sectors. The video derived from received radar echoes by all the antennas are sector identified and displayed on a single radar presentation.

Abstract: A connector assembly for efficiently coupling optical data from a fiber optic transmission line terminal to an electro-optic conversion device which may be associated with, for example, a hybrid electronics circuit substrate contained within a hermetically sealed enclosure or hybrid circuit package is disclosed. The connector is characterized by a unitary assembly of a generally tubular connector body adapted to removably receive and align a fiber optic terminal with an aperture therein, a transparent faceplate aligned with the aperture and hermetically sealed in the body, and an electro-optic conversion device mounted on the body in alignment with the aperture. The connector assembly may be tested prior to being hermetically sealed to the hybrid circuit package whereafter the conversion device may be connected to the hybrid circuit substrate and the entire hybrid circuit package hermetically sealed.

Abstract: An apparatus for testing digital logic circuits without a computer and associated software employs a pseudorandom stream of input data to produce an unstructured output data stream which is analyzed by an efficient data collector and analyzer. Test signal generation is implemented by a pseudorandom number generator and a pseudorandom clock/reset generator while the resulting test data at the output terminals of the device under test is analyzed by a cycle redundancy code checker. Fault localization is realized, with selectable localization and manual probe modes and circuitry is provided for an efficient self-test mode.

Abstract: A 360 degree fan beam scanning antenna which includes a transreflector created by a plurality of reflecting elements arranged on a surface of revolution formed about a generating axis and a feed antenna rotatable about the internal focal circle of the transreflector that provides an illumination beam for the transreflector which minimizes spillover and antenna pattern skewing.

Abstract: A continuous, self-supporting microwave transmission line along which ultra short pulses of microwave signals may propagate over distances of several hundred feet with minimum pulse distortion and signal attenuation. Propagation along the line is accomplished by an electromagnetic field thereabout that is sensitive to objects positioned in the proximity of the transmission line, a characteristic that may be utilized in short pulse reflectometer systems for monitoring and control of vehicles on a prescribed course.

Abstract: A four port apparatus is described for multimode electro-optic switching with reduced voltages relative to that required by the prior art. Two optical waveguides formed on an electro-optic substrate are in parallel relationship for a predetermined length to establish a coupling region, throughout which they are separated by a barrier having an index of refraction formed by, that is, lower than the index of refraction of the optical waveguides. Electrodes extending over the length and thickness of the barrier are deposited on both sides of the electro-optic crystal to which voltages may be applied to provide optical coupling or relatively high optical isolation between the two optical waveguides.

Abstract: An apparatus for storing tools and utensils in a vertical position which utilizes flexible magnetic material made into strips with each strip freely hanging from an end coupled to a mounting means. To provide additional mounting strength each strip of flexible magnetic material is reinforced in the coupling region with a plastic tape.

Abstract: An apparatus is described for multimode electro-optic switching with reduced switching voltages. A main optical channel is formed by providing a guiding electrode on an electro-optic substrate which is bounded on either side by barrier electrodes to which voltages are applied that possess polarities opposite to the polarity of the voltage applied to the guiding electrode. Quadratic behavior of Snell's law at glancing incidence is utilized to produce, via voltage excitation, a relatively large change in critical angle over a short section of barrier electrodes, which comprises a coupling region, to allow some portion of the guided light energy to couple from the main channel to a similar branch channel positioned in a coupling relationship thereto. Since the polarity of the barrier electrode is opposite to that of the guiding electrode, the guiding voltage is significantly reduced from that required by the prior art.

Abstract: A system is disclosed for transmitting information during a borehole drilling operation wherein a section of the drill string near the drill bit is utilized as a transmitting element of an electromagnetic wave propagation system. A receiving system at the surface uses a section of the drill string as one electrode and a metallic ring or ring of probes which penetrate the earth's surface at a given radius from the drill string as another electrode between which signal voltages are detected. In another embodiment, the receiving system comprises metallic rods at the surface which extend radially from the drill string. Signal currents induced in these radially extending rods are detected by a receiver coupled between the rods and the drill string.

Abstract: An apparatus and method is disclosed for utilizing a low power light source in conjunction with a continuously scanned light beam deflector to form unblurred images of a vocabulary of characters at a plurality of discrete positions. The light source illuminates a scanning deflector from which an angularly scanned beam is directed towards a lens, from which it emerges as a linearly scanned beam. This linearly scanned beam illuminates a linear fly's eye lens array from which a plurality of substantially stationary beams are emitted, each of which may provide an unblurred image at a preselected position corresponding thereto.

Abstract: A method and apparatus is described for multimode electro-optic multiplexing which provides high interchannel isolation. This isolation is achieved by utilizing voltage induced optical barriers to channelize optical signals and may be increased by positioning spoiler electrodes, which are energized with the channel barrier electrode, in each channel. These spoiler electrodes establish a varying refractive index in the median which deflects optical signals from the output port of the channel, thus providing the increased isolation. The spoiler electrode concept is also employed to provide a non-guided optical multiplexer/demultiplexer.

Abstract: A phase lock loop operable with narrow band filtering characteristics in-lock and wideband acquisition characteristics when an out-of-lock condition is detected. The phase lock loop comprises a phase detector coupled to a differential amplifier to which a step ramp voltage is also coupled when an a.c. signal, which indicates an out-of-lock condition, is coupled from the phase detector to an out-of-lock detector. The a.c. signal from the phase detector also causes a switch means to short out a narrow band filter which is serially coupled with a wideband filter between the differential amplifier and a voltage controlled oscillator. The frequency of the voltage controlled oscillator is caused to vary by the a.c. signal until lock-in is achieved at which time, the out-of-lock detector stops and holds the step ramp voltage at the value required to achieve lock and the switch means reintroduces the narrow band filter to the loop.