Abstract: A detector for detecting radiant energy includes at least detecting element and a detector readout element. The at least one detecting element substantially absorbs the radiant energy and exhibits a structural change in response thereto. The detector readout element, positioned in non-contacting proximity to the at least one detecting element, is responsive to the structural change of the at least one detecting element. The non-contacting detector readout element provides an indication signal corresponding to the structural change, whereby the corresponding indication signal is representative of the radiant energy detected by the at least one detecting element.

Abstract: A virtual beam system operating in an environment, including a non-compatible receiver, includes a transmitting subsystem and a receiving subsystem. The transmitting subsystem includes an array of transmitting elements and an element position encoded composite signal generator for generating an element position encoded composite signal. The array of transmitting elements is operatively coupled to the signal generator. The transmitting subsystem radiates the element position encoded composite signal via the array of transmitting elements. The receiving subsystem is responsive to the element position encoded composite signal and includes a receiving element and an element position encoded composite signal decoder for decoding the element position encoded composite signal. The receiving element is operatively coupled to the signal decoder.

Abstract: An improved open-path fast Fourier infrared spectrometer includes a circuit or algorithm which performs real-time, spectral alignment on measured interferograms to reduce measuremental errors. The improved spectrometer measures selected water vapor lines in a measurement path and compares the centerline of these measured water vapor lines to a reference library. From two or more such comparisons within the spectrometer bandwidth, the spectrometer calculates correction factors for the entire bandwidth. The improved spectrometer performs an overlap and add algorithm which applies the correction factors to perform bandwidth segment-specific shifts on subsequently measured interferograms.

Abstract: A digitally beam formed phased array antenna capable of both transmitting and receiving signals is constructed from a series of digitally controlled antenna elements. To transmit signals, a series of direct digital synthesizers is used to drive the antenna elements forming the phased array. Each direct digital synthesizer is programmed from a common digital processor with specific time and phase delay information such that the signals from the array combine to form a desired antenna pattern. To receive signals, signals from each antenna element in the phased array are processed by analog to digital converter. The digitized signals are then preprocessed in a time and phase delay preprocessor which receives time and phase delay information from a corresponding direct digital synthesizer prior to signal combining in a common digital processor.

Abstract: An ultra-linear chirp generator includes a voltage controlled oscillator (VCO) having a tuning characteristic which is naturally nonlinear, a linear ramp generator which generates a linearly ramping output signal having a linear slope characteristic with respect to time, a polynomial correction waveform generator which generates a polynomial correction signal, and a summer which is responsive to and sums the linearly ramping output signal and the polynomial correction signal. The summer generates a VCO tuning signal for tuning the VCO. The tuning signal corresponds to the linearly ramping output signal predistorted with a nonlinearity opposite to the natural nonlinearity of the VCO tuning characteristic. The linear chirp generator also includes a phase locked loop which is responsive to the output signal of the VCO and which has a reference frequency which is related to the repetition rate of the output signal of the VCO.

Abstract: A device for target prediction and collision warning for tracking objects in a region proximate to a vehicle includes a signal transmitter which provides first and second detection signals for at least partial reflection by an object located in a spatial region. The device further includes a signal receiver for receiving the deflected first and second detection signals corresponding to first and second parameter signals. A Fourier transform circuit is provided for receiving the first and second object parameter signals and generating first and second Fourier transform object parameter signals corresponding to relative range and velocity data of a target being tracked. The device includes a probabilistic neural network which preferably sorts the first and second Fourier transform object parameter signals corresponding to the relative range and velocity of a target being tracked.

Abstract: A system for increasing the power efficiency of a balanced amplifier driven antenna arrangement includes a push-pull class B power amplifier circuit which is responsive to a periodic, time varying input signal and generates at least two output signals in response thereto. The arrangement also includes a balanced antenna exhibiting a relatively high impedance at the second harmonic of the input signal. The arrangement further includes at least one transmission line operatively coupled between the power amplifier circuit and the balanced antenna to provide the at least two output signals to the balanced antenna. The at least one transmission line has a length which is one-eighth of the wavelength of the input signal or odd multiples thereof, and thereby reflects back to the power amplifier circuit a substantially short circuit at the second harmonic of the input signal.

Abstract: Apparatus for motion detection and tracking of objects in a region for collision avoidance includes a signal transmitter which provides first and second detection signals for at least partial reflection by an object located in a spatial region. The apparatus further includes a signal receiver for receiving the deflected first and second detection signals corresponding to first and second object parameter data signals. The apparatus further includes a Fourier transform circuit for receiving the first and second object parameter data signals and providing first and second Fourier transform object parameter data signals. The apparatus further includes a probabilistic neural network for receiving and sorting the first and second Fourier transform object parameter data signals without the use of a priori training data.

Abstract: A square anti-symmetric uniformly redundant array coded aperture includes transparent and opaque cells and exhibits a normal mask pattern at a first position and a complementary mask pattern when rotated to a second position rotationally offset by 90.degree. from the first position. The coded aperture is utilized in a coded aperture imaging system for imaging a source of non-focusable radiation such as a gamma ray or x-ray emitting source.

Abstract: A low power, low cost, millimeter wave (MMW) proximity sensor that provides over a 6:1 increase in minimum detection range (55 mm minimum) compared to standard 18 mm inductive proximity sensors preferably includes a low cost MMW Gunn oscillator, MMW detector and analog processing/driver circuitry. The sensor is preferably designed for 3-wire operation and will fit in a standard 18 mm tube.

Abstract: A circuit for generating a digital noise signal characterized by an evenly distributed frequency content for a particular frequency bandwidth of the digital noise signal includes a word signal generator for generating a random sequence of N-bit digital word signals with each cycle of a system clock signal provided to the word signal generator, where N is a non-zero integer. The noise generating circuit further includes a shaping circuit which transforms the random sequence into a shaped sequence of N-bit digital word signals, and a frequency synthesizer which is responsive to the shaped sequence and which generates the digital noise signal.

Abstract: Apparatus for detecting molecular vapors in an atmospheric region includes an interferometer which monitors light parameter data signals received and provides an interferometer light parameter signal corresponding to the light parameter data signals at a plurality of frequencies. The apparatus further includes an interferogram detector/converter which records and digitizes the interferometer light parameter signal to generate a plurality of discrete data points wherein each discrete data point corresponds to the interferometer light parameter signal at a specific frequency. The apparatus also includes a Fourier transform circuit for receiving the discrete interferometer light parameter signal and providing a Fourier transformed molecular parameter data signal. The apparatus further includes a probabilistic neural network for receiving and sorting the Fourier transformed molecular parameter data signals without the use of a priori training data.

Abstract: An ultra-linear chirp generator includes a voltage controlled oscillator (VCO) having a tuning characteristic which is naturally nonlinear, a linear ramp generator which generates a linearly ramping output signal having a linear slope characteristic with respect to time, a polynomial correction waveform generator which generates a polynomial correction signal, and a summer which is responsive to and sums the linearly ramping output signal and the polynomial correction signal. The summer generates a VCO tuning signal for tuning the VCO. The tuning signal corresponds to the linearly ramping output signal predistorted with a nonlinearity opposite to the natural nonlinearity of the VCO tuning characteristic. The linear chirp generator also includes a phase locked loop which is responsive to the output signal of the VCO and which has a reference frequency which is related to the repetition rate of the output signal of the VCO.

Abstract: An antenna mirror scanner for generating and directing an antenna scanner beam displaying constant polarization vectors. The antenna mirror scanner includes a non-rotating fixed-aperture antenna for transmitting and receiving an electromagnetic plane wave in a form of an antenna scanner beam and a planar reflector with a reflective planar surface. A rotational axis of the planar reflector is aligned orthogonally to a direction of propagation of the antenna scanner beam propagating towards or away from the reflective surface. A motor rotates the planar reflector to direct the antenna scanner beam incident on the reflective surface either into the non-rotating fixed-aperture antenna when the antenna mirror scanner is operating in a receive mode or from the non-rotating fixed-aperture antenna when the antenna mirror scanner is operating in the transmit mode.

Abstract: A coaxial-to-coplanar waveguide connector is used for interconnecting stripline compatible devices utilizing coaxial cable. The connector is formed at the end of a length of coaxial cable embedded within a circuit board. The connector generally has a substantially semi-circular connection section. The connection section includes a conductor partly surrounded by an electrically insulative dielectric which is partly surrounded by a shield. An electrically conductive sheet is used to couple the shield to a ground plane of the circuit board. Electrically conductive ribbon is connect the conductor to a stripline compatible device. The coaxial-to-coplanar waveguide connector may be fabricated by coating a dielectric board with an adhesive material and then routing a length of miniature coaxial cable in the adhesive. Conductive material and dielectric material are consecutively laid upon the dielectric cable board.

Abstract: A digital signature built-in-test (BIT) device for testing a digital circuit includes circuitry for compressing test data received from the digital circuit. The test data compressing circuitry may include one or more linear feedback shift registers (LFSR), which compresses the test data and supplies a signature data word corresponding to the test data compressed. Circuitry for enabling the test data compressing circuitry for a predetermined period of time is also included. The enabling circuitry provides an enabling signal to the test data compressing circuitry. The signature data word from the test data compressing circuitry is stored in a buffer memory circuit. Control data is received by the digital signature BIT device from a remote processor. The control data is received and processed by a control circuit, which circuit supplies control signals to the test data compressing circuitry, signature data word storing circuitry and the enabling circuitry.

Abstract: A phased array antenna system capable of scanning at rates faster than the information rate of signals being received to prevent the loss of information during the scanning process. The sensitivity loss due to sampling usually encountered is avoided. The present invention is an improvement on a prior art system that avoids the sensitivity loss in that the present invention also avoids the frequency selectivity inherent in the prior art system.The array antenna system is comprised of the means to form multiple, time-sequenced outputs, each output corresponding to a different beam of sensitivity. The beams scan the full coverage sector and together with the other outputs form a contiguous set of beams that both fill the coverage sector at any one time and also synchronously scan the full coverage sector.

Abstract: Integrated circuit structure and processing is provided for a high power limiter including at least a first anti-parallel array of monolithically integrated Schottky diodes. In a further embodiment, integrated circuit structure and processing is provided for an MMIC, microwave and millimeter wave monolithic integrated circuit, including an amplifier and a high power limiter monolithically integrated on the same substrate.

Abstract: A microwave crosspoint blocking switch matrix and assembly employing multilayer stripline and pin diode switching elements is employed to selectively electrically couple and decouple input transmission lines to output transmission lines without severance of the transmission lines and insertion of a series switch. The microwave crosspoint blocking switch matrix assembly employs pin diode arrays coupled to input and output transmission lines at respective crosspoints. In order to route a signal from a specific input line to a selected output line, the pin diode array at the input/output transmission line crosspoint is activated and each transmission line is shorted at points one-quarter wavelength distant from the crosspoint to reflect, ideally, an infinite impedance at the interconnection point. Therefore, a desired signal cannot propagate in any direction except from the selected input line to the desired output line.

Abstract: A cylindrical phased array antenna system capable of scanning at rates faster than the information rate of signals being received so that no information is lost by the scanning process. The array is configured to add the capability to provide multidimensional separation of multiple signals and to eliminate the sensitivity loss due to sampling. The cylindrical phased array is comprised of the means to decompose the distribution of current on the radiator elements caused by wave incidence into component signals which are the Fourier spatial harmonics of the distribution, heterodyne means to differentially phase shift these component signals at rates exceeding 4 .pi. radians per cycle of the highest frequency present in the information content of the incident wave, and means to form multiple complex-weighted sums (beams) of the component signals.