Abstract: The invention comprises an automated system 10 for the accurate positioning of movable parts bins 16 in relation to a preferred fixed location 26. The automated system consists of a number of movable parts bins 16 arranged on a conveyor 14 which is driven by a drive mechanism 18. The drive mechanism 18 controllably moves the conveyor 14 and therefore the bins 16 to desired locations in association with a coarse position sensor 24 and a final approach sensor 26. Both the sensors and the conveyor drive mechanism are interconnected with an electronic controller 28. This electronic controller monitors the position sensors in order to control the drive mechanism in a manner which positions the preselected parts bin at the desired location.

Abstract: The extinction coefficient of atmospheric aerosol is measured by an instrument in which a single light beam from a graybody source is alternately directed through two similar optical paths to a detector. Each optical path traverses an equal length region of ambient air. Aerosols are filtered from the ambient air region of one optical path .The detector measures the modulation of the incident radiation and its output is a function of the extinction coefficient of the ambient air under test. A second detector is used to monitor the beam power. Processing electronics compute the extinction coefficient of the ambient air under test from the detector outputs. The ambient air regions of the two beam paths are alternately filtered for improved performance.

Abstract: Discrimination between sidelobe and main beam reception of interference signals in a lobe on receive only radar is accomplished by a method of operation in which interference signals are stored and averaged for the radar receive beam positions of boresight, up, down, left and right. Interference signals received at boresight are compared with interference signals received at each off-boresight beam position. Interference signals received at boresight are also differenced with interference signals received at the off-boresight beam positions and the results are compared with beam width defining threshold factors. The determined values are applied to logic functions that indicate reception of interference signals outside of the main beam pattern.

Abstract: The simulation of a two-wire rheostat is accomplished by an analog output circuit whose value is digitally controlled. It comprises a four-quadrant multiplying digital to analog converter (MDAC) and a current booster including active elements in the feedback loop of an amplifier. The digital rheostat acts as a variable resistance whose value is controlled by a digital controller and can accommodate either AC or DC excitations. The unit forms a negative feedback loop containing only solid-state devices and relies on fixed resistors for accuracy.

Abstract: The reading of the presence or absence of a pencil or similar mark at various locations on a sheet of paper is accomplished by an optical Mark-Reader comprised of a completely solid state sensing mechanism with no moving parts. The Optical Mark Reader (OMR) contains a matrix of light sensitive transistors with their geometry and logic circuits capable of being tailored for a plurality of answer sheets. The internal logic circuits enable certain sections of the page to be read, generate a delay time while the data is being gathered, tell the host computer when the data is complete, and resets the OMR operator control system for successive page readings. Finally, the internal logic circuits and output bus of the OMR takes the "raw" data from the answer sheets and presents information on an output bus in a format allowing any computer (even a micro-computer) to be the host computer.

Abstract: Improved gain control in a multiplexed adaptive array processor having main and a reference channel receiver is achieved by means of an AGC circuit controlling the gain of the reference channel receiver over its dynamic range, an AGC circuit slaved to the reference channel receiver AGC circuit controlling the main channel receiver, and a separate AGC circuit controlling the output of the main channel receiver.

Abstract: A microstrip L-band bipolar dielectric resonator stabilized oscillator (DRO) devised in a moderate size (2'.times.5".times.3.6"), low-cost, reproducible circuit. Embedment of back to back varactors in the DRO provide voltage tuning for phase lock application without compromise of noise performance. Extremely low phase noise with a low l/f noise corner is achieved and the DRO is essentially constant in frequency and output power over temperature, all due to unique circuit configuration. An internal buffer amplifier and dc regulatory circuits provide a DRO that is insensitive to frequency pulling due to load changes and power supply voltage leads. New standards of performance are accomplished that permit simplified stalo configuration with lower phase noise.

Abstract: The detection of low-flying aircraft is accomplished using both a microphone and geophone as sensors and a signal processing system for measuring the correlation between the seismic and acoustic signals. The signal processing system contains two amplification and band-limiting circuits, a delay circuit, an adaptive noise cancelling circuit, two signal smoothing circuits and a comparison circuit. The two amplification and bandlimiting circuits enhance a selected portion of the seismic and acoustic signals received by the sensors. The optional delay circuit is applied to the input acoustic signal, allowing the user the option of sensing or rejecting the detection of jet aircraft. The adaptive noise cancelling circuit generates an error signal by subtracting the signal components which are correlated between the seismic and acoustic signals from the input seismic signal. The first signal smoothing circuit improves the quality of the input seismic signal for comparison.

Abstract: The testing of radar systems is enhanced with the use of clutter generator that simulates realistic terrain echo returns which are provided in real-time. A fast array processor is used in combination with a Fourier Transform processor to produce a complex digital output having time, frequency and magnitude information corresponding to the composite echos from thousands of points. A digital-to-analog converter filters the output and a single-sideband mixer converts the digital output to a radio frequency signal.

Abstract: The rapid and precise control of an aircraft flight path is obtained by a continuous blending of direct lift and conventional longitudinal control system commands by a unit that consists of a combination of a linear gradient and breakout element, a blending integrator, a nonlinear element, a Direct Lift Limit element, an interconnect gain element, and three summing junctions. Direct lift is blended with conventional control as the pilot manual command is conditioned by the linear gradient and breakout element to provide the command signal to the first summing junction. The difference between this command and the output of the blending integrator is applied to the recentering nonlinear element. The direct lift command is obtained by passing the output of the recentering nonlinear element through the direct lift limit element. The second summing junction is used to reform the total system command which is applied to the third summing junction.

Abstract: Using an electronically scanned phased array antenna, a technique is developed for aligning a broad elevation beam along an isodop for use in synthetic aperture mapping. A beam steering controller algorithm for practical implementation of the technique is described. Implementation is realized by means of a beam steering controller and the radar computer. The controller first finds the space stabilized row and column for a given phase shifter. A look-up table furnished by the radar controller provides a slope correction as a function of row. The slope is multiplied by the element column to give the correct linear phase function. This term is then subtracted from the term used to point the beam peak.

Abstract: In combination with an envelope detector in a radar system, a bias compensation circuit consisting of a programmable read-only memory and a binary adder produce an unbiased envelope detection signal. The bias compensation circuit adds one to the output of the detector based upon whether the minimum of the I and Q (inphase and quadrature) signals is odd and the maximum even. It is capable of compensating for both normal envelope detection and the multiple divide-by-two case. As a result the dynamic range of the radar can be increased without the necessity for extensive additional hardware.

Abstract: In a radar receiver, a distribution sensitive constant false alarm rate processor derives the clutter threshold level from the average magnitude of echo return signals. The threshold level continuously adjusts to the changing conditions of the radar environment and correctly corresponds to the false alarm rates which may be varied by the user of the host radar system. The clutter threshold is then used to suppress clutter returns following either a Rayleigh distribution or a Weibull distribution.

Abstract: A countermeasures system technique for destroying threat radar frame of reference. Automatic change of false target pattern is accomplished by any one of three different switching schemes or by any combination of them. The switching schemes comprehend (a) changing polarity of digital counts delivered to system range position program matrix inputs; (b) alternately enabling and disabling selected outputs of the range position program matrix, and (c) interchanging selected input gates of the system angle position program matrix.

Abstract: Very wide field of view optical surveillance is realized without scanning or moving parts by means of an integrated multiaperture optical system. The system utilizes light gathering optics in the form of an array of eyelets or lens apertures that direct in-coming light onto a detector layer. The detection layer consists of individual detectors, more than one to a lens. Under the detector layer there is a correlation layer, which contains a memory cell for each detector and circuitry which connects to neighboring memory cells according to a hard wired program. Below the correlation layer is a processing layer which contains microprocessor circuitry allowing further processing of the acquired information. Outlines of objects seen by the system are defined by the microprocessor circuitry using an edge detecting routine. A detected object is identified by correlation with a single number recognition coefficient.

Abstract: The acquisition of phase lock to a reference frequency by a signal acquisition system is accomplished using a voltage controlled oscillator, a wideband frequency discriminator, a prepositioning circuit, and a phase lock loop. The voltage controlled oscillator is prepositioned within a loop bandwidth of the reference frequency by the prepositioning circuit and the wide band frequency discriminator which provide coarse tuning. The voltage controlled oscillator achieves phase lock with the reference frequency when it receives the fine tune signal from the phase lock loop. Using both the discriminator and the phase lock loop allows fast acquisition without the need to calibrate the voltage controlled oscillator. Since the discriminator pull-in range is much larger than the phase-lock loop bandwidth, the number of bits can be much smaller than in an acquisition circuit using a digital prepositioning circuit alone.

Abstract: Enhanced availability and survivability of communications between geographically remote locations with a minimum of redundancy of transmission facilities and media is provided by a survivable bus network capable of providing continued interprocessor or other communications in the event of multiple bus outages. It consists of multiple busses, bus isolation device (BIDs) and two types of network interface processors (NIPs). The BIDs electrically isolate bus segments on either side of a connection so that if a fault occurs only the segment containing the fault will be affected. The first type of NIP connects to one bus and performs the usual function of providing an electrical and software interface between the network and one or more subscriber processors. The second type is a bridge which performs these same functions but connects to two busses and has the capability to transfer traffic as it appears on either bus to the other.

Abstract: A signal processing system, which operates in parallel with the outputs of sensors of an adaptive array, for quickly nulling multiple jammers. The processing system includes a set of parallel combiners and an apparatus for updating a signal weight which is applied to the sensor outputs. The parallel combiners mix a weighing function with each sensor output and provide a resultant output signal which has been cleared of interference from jamming. Part of the resultant signal is fed to the apparatus for updating the signal weighing function for further mixing with sensor outputs. The parallel operation of the combiners with each sensor output provides fast nulling effects.

Abstract: This invention is directed to a narrow band filter for eliminating out-of-band noise in the oscillator signal of a doppler radar system. It provides a very high Q filter derived from a Bulk Acoustic Resonator's (BAR) high Q, L-Band response and uses thermal feedback to lock the BAR's response band onto the input frequency. The BAR is a very narrow band filter with a Q near 40,000 and a comblike frequency response having passbands occurring every 5 MHz, approximately. The comblike response of the BAR shifts down 60 KHz for every 1.degree. C. rise in temperature. In this invention a frequency sensitive heater is used to move the response comb of the BAR up or down in accordance with changes in the frequency of the incoming signal. The input frequency can be allowed to drift and the heat source will produce more heat or less heat, keeping the response right at the input frequency.

Abstract: The applique rate converter permits a digital multiplexer to support any data rate less than half of its input port design rate. The applique rate converter develops a composite data stream consisting of alternate data bits and data boundary bits. The data boundary bits change state at each new data bit (corresponding to a change in the data clock.) The composite bit stream is increased to the output data rate by means of a circuit called the `synchronizer`. At the demultiplex side of the applique, the data is separated from the composite stream by a decoding process and, if necessary, the data stream is rate smoothed. The major sections of the applique rate converter are the `synchronizer` at the multiplex side and the data separator and rate smoothing circuits at the demultiplex side.