Abstract: The invention relates to a method and device for monitoring data flow, specially to provide radar data for air traffic control systems. In order to detect data supply failures and to provide an automatic replacement supply, the data which is transmitted is computed at the output of the data transmission device at parameterable time intervals, whereupon the data flow is reproduced, the measuring values are stored during several intervals and compressed into an average value. When a new value is inputted, the oldest value is erased. The average value is used as a starting value for a sensitivity curve which generates a time window for periodic comparison of added measuring values for an error detector which signalizes a total failure of measuring values in a predetermined time unit and initiates a selection mode to access a predefined data source in an appropriate data network and the data is inputted into the respective data supply system via interfaces.

Abstract: An automated simulator for radar and sonar applications. The inventive simulator is implemented in hardware and generates current parameters with respect to a simulated target in response to a plurality of initial values with respect thereto. In the illustrative embodiment, the initial values include range, velocity, and acceleration and are stored in first, second and third register respectively. In the best mode, the invention is implemented in a field-programmable gate array. The inventive target simulator also includes a range delay circuit for generating a simulated return from the simulated target. The range delay circuit includes logic for determining whether a simulated pulse train to be received is ambiguous or unambiguous and adjusting the pulse repetition rate of the pulse train accordingly. The range delay circuit calculates die initial time that a packet needs to make the trip to and from the target.

Abstract: AN FM pulse Doppler radar apparatus performs pulse modulation of modulating waves having repeatedly increasing and decreasing frequency, transmits thus modulated waves, receives at each range gate having an interval equivalent to a pulse width, reflected waves reflected from an object, determines a distance according to the range gate, and calculates the distance to the object and the relative velocity of the object based on the difference between frequencies of the transmission waves and the received waves. The apparatus includes a velocity determining unit for determining velocity of the radar-mounted vehicle and a comparison-and-detection unit for comparing the detected distance according to the range gate and the distance calculated based on the difference between the frequencies of the transmission waves and the received waves.

Abstract: A linear phase detector circuit enables locking of two frequency sources which can operate in the range of 10 GHz with a minimal frequency offset, such as from 0 Hz to 50 KHz. With the frequency sources operating at frequencies F1 and F2 with an offset F2−F1 or F1−F2, the phase detector generates a DC signal indicating a phase offset between a signal F2−F1 or F1−F2 derived from the frequency sources and a reference operating at the desired offset F2−F1 or F1−F2, while eliminating any 2(F2−F1) or 2(F1−F2) component. In this way, the phase detector allows a substantially higher loop bandwidth than the offset F2−F1 or F1−F2, and allows phase tracking independent of the offset. The phase locking circuitry is useful in applications such as providing a variable Doppler shift in a radar signal.

Abstract: A method and apparatus are provided to allow altimeter data sets from multiple altimeter satellites to be used together. The measurable portion of geographically correlated orbit error (GCOE) is removed from the altimeter data sets, thereby allowing the data sets to be combined consistently. The GCOE structure for a reference data set is estimated through crossover difference analysis. The unmeasurable portion of the GCOE is not removed, although the spatial structure of this portion is determined. A reference mean sea level (SL) is corrected for the measurable GCOE and is then used as a reference surface for estimating the GCOE structure for an independent altimeter data set. This is performed by examining crossover differences between the altimeter mean SL and the reference mean SL at the multimission crossover points. The change in sea surface height (SSH) between the input data set and the reference data set is determined.

Abstract: A radar apparatus which can detect an abnormality such as a drop in sensitivity, or a fault in the radar apparatus comprises; a transmission device and a reception device of a beam, and a processing unit for detecting the position of a target object from the transmission signal and the reception signal, and the processing unit comprises a signal separation device, a roadbed reflection analysis device and an abnormality judging device, and the radar apparatus is judged to be abnormal when a reflection signal from a roadbed is not detected by the roadbed reflection analysis device with respect to a low-intensity spectrum signal separated by the signal separation device.

Abstract: Faraday Rotation causes rotation of the plane of polarization of plane polarised radiation emitted by a radar e.g. a synthetic aperture radar and, if returns polarized in orthogonal planes are measured at the synthetic aperture radar in order to determine polarimetric characteristics of the ground, which could show up features of the ground such as crop patterns, the measurements made at the SAR are contaminated by the Faraday Rotation. In the invention, the transmitted plane polarized beam is pre-rotated in transmitter 9, the radar returns in receiver 13 are mathematically adjusted in signal formatting 14, 15 to compensate for just the pre-rotated angle, to produce data streams on downlink 16 uncontaminated by the Faraday Rotation.

Abstract: A reply is received from aircrafts for calibration in response to an interrogation of SSR stations to detect transmission timing of the interrogation of the SSR stations and directly-facing timing of antennas of the SSR stations and thus detect a position of an arbitrary aircraft based on the transmission timing and directly-facing timing and the reply from the aircraft.

Abstract: An apparatus and method for generating an electromagnetic environment in which the free field, plane wave response of electronic systems of an electrically large (greater than several wavelengths in its longest dimension) object, or objects, under test can be measured in the electromagnetic radiating near field of the transmitter array apparatus. The apparatus comprises: (1) one or more transmitting station(s), each station home to an array of radiating elements; (2) a software operating system and computer that controls the electronic circuits of the apparatus and executes an optimizing algorithm based on a Genetic Algorithm to control the radiation of each transmitting station; and (3) mechanical and electrical circuits that enable the apparatus to conduct self calibration and adjustment as required. In operation, the apparatus is placed and distributed about an object under test.

Abstract: An electronic counter-measure receiver can be colocated with a threat simulator radar, which transmits a radar signal. As a pulsed-Doppler signal, this transmitted radar signal is sampled as a reference signal by the receiver to determine quadrature, coherent matched filter coefficients. A return signal is received and processed with the reference signal as quadrature signal components with the quadrature, coherent matched filter coefficients within a matched filter. The return signal is processed as a first intermediate frequency via a mixer and local oscillator and a second quadrature intermediate frequency via a digital local oscillator and mixer. A fast Fourier transform is performed to determine Doppler information. In a continuous wave transmission for sampling arbitrary but unevenly spaced in time pulses are generated from a pulse generator source internal to the receiver.

Abstract: A TCAS receiver/transmitter which uses an improved calibration scheme for improving the ability of the device to transmit in a narrow directional field where the device uses the transmitter frequency source to generate signals for calibration purposes. The calibration uses a technique of simultaneously transmitting from two antennas and manipulating the phase of the signal through successive settings. The signals are monitored by the remaining two antennas and calibration adjustments are made in response thereto.

Abstract: An antenna test range uses direct spread-spectrum based test signals to test the performance of an antenna. Since a spread spectrum waveform has high autocorrelation properties with itself and high cross-correlation properties with signals other than itself, in the receiver coupled to the antenna it is possible to effectively electronically reject all unwanted signals that may be present in the test range, and thereby allow both main beam and off-axis performance of the antenna to be completely and accurately measured.

Abstract: Methods and apparatus for calibrating a Wireless Location System to enable the system to make highly accurate TDOA and FDOA measurements are disclosed. An external calibration method in accordance with the present invention comprises the steps of transmitting a first reference signal from a reference transmitter; receiving the first reference signal at first and second receiver systems; determining a first error value by comparing a measured TDOA (or FDOA) value with a theoretical TDOA (or FDOA) value associated with the known locations of the receiver systems and the known location of the reference transmitter; and utilizing the first error value to correct subsequent TDOA measurements associated with a mobile transmitter to be located.

Abstract: The radar apparatus of the present invention comprises a beam transmitter for radiating a radar beam, a beam receiver for receiving a reflected signal, a processor for calculating the position of the object, and a malfunction detecting device for detecting a malfunction of the radar apparatus. At least one of the area irradiated by the beam transmitter and a receiving area of the beam receiver overlaps with a movable area of a wiper blade of the wiper device, and the malfunction detecting device estimates that the radar apparatus is malfunctioning if a wiper passing signal to be detected does not appear in an output signal of the processor while a wiper movement detecting device detects that the wiper device is activated.

Abstract: A method and apparatus for generating microwave signal frequencies. An incident reference signal is provided. A first stimulus signal is also provided, the first stimulus signal having a first polarization and having a first predetermined relationship with the incident reference signal. A second stimulus signal is also provided, the second stimulus signal having a second polarization and having a second predetermined relationship with the incident reference signal. The incident reference signal is split into a first polarization reference signal and into a second polarization reference signal. The first stimulus signal is coupled with the first polarization reference signal to provide first polarization mixed signals. The second stimulus signal is coupled with the second polarization reference signal to provide second polarization mixed signals.

Abstract: To calibrate a transmitter and/or sender for controlling a beam forming network, each of the control signals is divided into a plurality of frequency segments. The control signal of each frequency segment is multiplied by complex coefficients so that the transmitter output signals, after passing through a reference receiver, are identical to the respective control signals. A similar adjustment is performed for the receive direction. The method and the device allow the same beam characteristic.

Abstract: A method and apparatus for optimizing radar system performance is provided that is independent of any specific radar application. In one embodiment, an optimization system (110) includes an optimization engine (112) and various input modules including constraint module (114), a variable module (116) and an objectives module (118). The input modules provide information sufficient to define an optimization application under analysis. Based on these inputs, the optimization engine (112) identifies an appropriate optimization model and determines optimal radar system parameter values. In this manner, the optimization engine (112) need not be preprogrammed with knowledge of the application under consideration, and is applicable in a variety of context involving different radar system types.

Abstract: Novel test mounts are defined for a radar cross section testing apparatus that allows a supported object to be tested without interference from the test mount. This includes prescribing a diameter of about 0.61 wavelegths for a cylindrical test mount; maintaining a ratio for the test mount's characteristic dielectric constant and magnetic permeability of about one; and/or installing a frequency transposing apparatus to convert the frequency of radar pulses directed toward the test mount to off-frequency echoes.

Abstract: An antenna test range uses direct spread-spectrum based test signals to test the performance of an antenna. Since a spread spectrum waveform has high autocorrelation properties with itself and high cross-correlation properties with signals other than itself, in the receiver coupled to the antenna it is possible to effectively electronically reject all unwanted signals that may be present in the test range, and thereby allow both main beam and off-axis performance of the antenna to be completely and accurately measured.

Abstract: This invention identifies a process for determining the performance of radio frequency (RF) links in the Army's Enhanced Position Reporting System (EPLRS) with a high level of statistical confidence. The method includes determining a statistical difference between a mean propagation loss for an EPLRS RF link based on measured RF propagation loss and TIREM calculated RF propagation loss, establishing a margin of error based on said statistical difference to arrive at a confidence level of the RF propagation loss, determining a computed S/N based on the confidence level, for the benign and jamming case, and determining a PCOM value based on the computed S/N value.

Abstract: A time-domain baseband measurement method measures modulated microwave signals typically used in communication systems by converting microwave signals to baseband before measurement for improved accuracy compared to direct measurement at the microwave frequency. A downconverting receiver is first characterized using a prior characterization method and then the modulated microwave signal is applied to the downconverting receiver and the response of the downconverting receiver is removed to provide an accurate characterization of the modulated microwave signal. Such an accurate measurement of the modulated microwave signal can be used for communications system performance verification as well as for characterizing communications devices and systems. One particular application is the measurement of input/output characteristics of nonlinear power amplifiers using such modulated microwave signals.

Abstract: The present invention is an apparatus and method for calibrating a downward viewing image acquisition system. The apparatus comprises a calibration panel with calibrative material of known reflectivity. The calibrative material coats the panel surface or is pulled across its surface or pulled across its frame so as to maintain a consistent reflectivity and/or emissivity. A housing is provided which protects the calibration panel from the deteriorative effects of natural elements. The housing alternately exposes the calibration panel to the downward viewing image acquisition system as a calibration exposure and covers the calibration panel after the calibration exposure.

Abstract: A digital radar landmass simulator (DRLMS) used for stimulation testing pulse radars, wherein the DRLMS operates by synthesizing time-overlapping chirp waveforms using finite impulse response filters. The DRLMS, thus, effectively generates many overlapping complex pulse signals from many radar reflectors representing a semi-infinite continuum of closely spaced targets. The DRLMS also allows the insertion/injection of the effects of Doppler shift and jamming into the synthesized modulated signal.

Abstract: An automotive obstacle detecting system is provided which includes a radar to measure the distance to a target present within a detectable zone. The system monitors a distance limit measurable by the radar and determines a reduction in ability to measure the distance to the target by comparing the distance limit with a given reference value.

Abstract: Systems and methods are disclosed for providing calibration of the phase relationships of signals simulcast from a transmission system. In a preferred embodiment, a calibration signal is introduced into the transmission system and provided to various antenna elements. Samples of the calibration signal are taken at a point very near the antenna elements so as to sample phase shifts introduced by the transmission system. The signals of sets of the antenna elements are combined after sampling for transmission down the antenna mast to the active circuitry of the present invention. Accordingly, the present invention operates to selectively energize antenna elements of the sets so as to provide a single calibration signal down the combined signal path. Through reference to sampled signals one at a time, the present invention determines a necessary phase adjustment to result in the desired phase relationship of the signals at the antenna elements.

Abstract: The present invention relates to the problem of calibrating an antenna system (23) comprising an electrically controlled antenna (25) using a test antenna (45) arranged near the electrically controlled antenna, with the possibility of calibrating during operation, when disturbing reflections or other unknown signal influences are present when signals are transmitted between the test antenna and the electrically controlled antenna or between the electrically controlled antenna and the test antenna. The electrically controlled antenna comprises a number of modules (27-(1-N)) having means (91-(1-N)) for controlling the complex amplification of the modules. Each module is arranged with a commandable reference mode at reception and/or transmission.

Abstract: A test station for testing the performance of an automotive Forward Looking Sensor (FLS) in detecting one or more targets in a predetermined scene within the field of view of the FLS. The test station includes a chamber having a first end at which the FLS is disposed and a second end at which a Transmit/Receive Test (TRT) system is disposed. The TRT system includes an antenna array responsive to an RF signal transmitted by the FLS and a Transmit/Receive (TR) processor for processing the received signal in order to simulate the predetermined scene and for transmitting the processed signal back to the FLS. The TR processor includes at least one Transmit/Receive Radio Frequency (TR RF) processor module for processing the received RF signal by selectively shifting the frequency and/or adjusting the amplitude of the signal.

Abstract: A method and apparatus for testing an antenna control system. The antenna control system having an antenna control unit electrically coupled to an antenna pedestal. The present invention simulates the operational environment of the antenna control system and records the systems responses to the simulation. The responses are then analyzed and the antenna control system is adjusted to correct errors.

Abstract: A compact RF monopulse receiver circuit having a relatively low noise figure which is particularly useful for operation in the millimeter wave frequency range is described. The compact monopulse receiver finds use in small projectile and small missile applications. Also, a combination of transmit signal protection circuitry and receiver circuit architecture allows the RF monopulse receiver circuit to operate in a missile or other projectile which utilizes high RF power transmit signals. The RF monopulse receiver circuit can directly provide a radiation pattern for target detection and tracking or alternatively, the RF monopulse receiver circuit can function as a monopulse feed circuit which can be used, for example, in a quasi-optically fed reflector antenna.

Abstract: The inventive connection mechanism uses a tongue and groove connection in combination with a RF gasket. Fixture panels are constructed by placing the tongue of one panel into the groove of another panel. The gasket is pre-positioned in the groove, such that the tongue compresses the gasket to the manufacture's specified compression thickness. The panels can then be secured using fasteners. RF fixtures constructed with such connection mechanisms can be rapidly assembled. Moreover, the RF fixtures can be rapidly taken apart to allow for maintenance of the internal elements of the fixture. The use of the tongue and groove connection with the RF gasket provides an RF sealed connection. Thus, the fixture is not subject to interference from undesirable external RF signals.

Abstract: The present invention provides a broad band, multi-band radar detector which may be configured so as to have two or three down conversion stages. There are three mixers in the circuit, the second of which has a frequency synthesized local oscillator which is governed by a phase lock loop feedback circuit under the control of a microprocessor, so that the output frequency of the second local oscillator may be varied by an amount equal to .+-.f.sub.adj. The first local oscillator is also under the control of the microprocessor, so that a specific intermediate frequency signal from the first mixer may be derived. By varying the frequency of the second frequency synthesized local oscillator, the tuning range of the radar detector may be increased in each frequency band of interest by an amount equal to .+-.f.sub.adj for all frequency values in each respective frequency band of interest.

Abstract: A moving target simulator for testing a radar system has a radio frequency receiver, a digital radio frequency memory in electrical communication with the radio frequency receiver for storing a signal received thereby, a digital delay circuit in electrical communication with the digital radio frequency memory for providing a time delay between reception and transmission of the radio frequency signal, an amplitude modulation circuit in electrical communication with the digital radio frequency memory for modulating an amplitude of the radio frequency signal, a Doppler modulation circuit in electrical communication with the digital radio frequency memory for providing a Doppler-modulated signal, and a radio frequency transmitter for transmitting the radio frequency signal after it has been delayed, amplitude-modulated, and/or Doppler-modulated.

Abstract: A test beacon for a radar system includes: a first antenna for receiving a search signal and transmitting a processed search signal, a second antenna for receiving a tracking signal and transmitting a processed tracking signal, a first signal processor for shifting the phase of the received search signal and adjusting it to a predetermined level, a third signal processor for shifting the phase of the received tracking signal and adjusting it to a predetermined level, a search/tracking signal delaying unit for receiving the search and tracking signals phase-shifted by the first and third signal processors, delaying the signals for a predetermined time period, and distributing and outputting the delayed signals, a second signal processor for receiving the delayed search signal and filtering a frequency band of the search signal and adjusting the signal to a predetermined level, a fourth signal processor for receiving the delayed tracking signal and filtering a frequency band of the tracking signal and adjusting

Abstract: A self-contained, single-unit test and calibration unit for Doppler-effect speed measurement devices (radar guns, etc.) is provided. The inventive unit is capable of performing manual, semi-automatic and automatic measurements on radar guns insuring no "missed" steps in the certification process. The unit is optionally supported by a general-purpose, digital computer such as a "PC" which may, in turn, be linked to a remote facility via modem or similar communication strategy. Either a local or a remote computer may oversee the test, calibration and certification processes. The inventive unit allows for fast and accurate certification of radar guns in the field by operators of only minimal technical skill thereby saving expense and time as radar guns no longer must be shipped to a remote certification facility.

Abstract: A satellite integration and testing system and method in which a satellite (12) is assembled and many tests are performed on it in a single test chamber (10), thereby avoiding multiple setup and tear-down operations required if multiple test chambers are used, and avoiding the need to move the satellite between test chambers.

Abstract: In a method of adjusting the axis of a car on-board radar, especially, a car on-board mono-pulse radar having the function of transmitting radio waves, light or ultrasonic waves, a car axis and an offset axis are set and the mount angle of an antenna offset-mounted on the offset axis can be adjusted with high precision and with ease through a reduced number of process steps.

Abstract: A measurement chamber which surrounds a target of interest intersected by a line defined by focal points associated with the measurement chamber and which separates and extracts scattered signals from the measurement chamber, includes a chamber having an interior defined by rotation of a nonlinear curve about the line, and first and second focusing elements which couple the scattered signals out of the measurement chamber. According to one aspect of the invention, the measurement chamber further includes first and second absorbing material sections which absorb the scattered signals, and which are disposed proximate to the distal ends of the first and second focusing elements, respectively.

Abstract: The present invention relates to a method for determining a phase correction value in a radar apparatus provided with an array antenna comprised of a plurality of antenna elements as a receiving antenna. The method for determining the phase correction value according to the present invention has a first step of obtaining a first correction value for each channel for correcting a phase shift between channels of the plural antenna elements, a second step of obtaining a second correction value for each channel for correcting a deviation between an electrical center direction and a front direction obtained with phase correction using the first correction values, and a third step of obtaining a final correction value for each channel from the first correction value and the second correction value, and the method determines such a phase correction value as to match the direction of 0.degree. with the electrical center direction for each channel.

Abstract: A method and apparatus for calibrating azimuth boresight in a radar system. Antenna boresight misalignment can cause radar systems to inaccurately determine the position of targets relative to a platform vehicle. These errors can be corrected by detecting and accurately measuring a boresight offset angle defined as the angle between the radar antenna boresight and the direction of travel of the host platform vehicle. Several antenna boresight calibration techniques are described. A first technique calculates the boresight offset angle by obtaining target range and azimuth angle measurements at two instants in time. The boresight offset angle is determined by the geometric relationship of the offset angle, target range and azimuth values obtained at two successive time instants. A refined approach obtains target range and azimuth values at several successive time instants, calculating interim boresight offset angles at each time instant.

Abstract: A leakage calibration and removal system and method estimates the complex in-phase and quadrature phase (I/Q) components of a leakage signal for each beam location in the sampled down-converted radar signal in a radar system (10). In a digital embodiment, the stored leakage calibration signal (264) is subtracted (206) from the sampled radar signal, and the resultant signal is processed (208, 210, 212) to detect targets. A leakage calibration process (250) is activated if a leakage signal test (214) indicates a problem for a sufficient number of consecutive scans (216), wherein for each beam location, M consecutive I/Q waveforms are averaged (252), known targets are removed (254, 256, 258), and the resulting signal is scaled (262) and stored (264) as a new leakage calibration signal if the variance is within acceptable limits (262).

Abstract: An auto-test device for a radar includes at least one transducer located in the field of radiation of the radar microwave transmission, the transducer being configured to intersect a part of the radiated energy and to send it back to a receiver so as to create, in the receiver, a test signal modulated by beats of the transducer. The device further includes a synchronism mechanism configured to excite the transducer in synchronism with a sub-multiple of the frequency of sampling of a reception signal. The transducer is placed such that the receiver receives a test signal with a mean value close to zero.

Abstract: A method and apparatus for calibrating transmission and reception paths of a group antenna with an adaptive radiation pattern is provided, in which one transmission signal after the other is transmitted over each transmission path (DA1, . . . ,DAN; Tx1, . . . ,TxN; DP1, . . . ,DPN), a signal portion is decoupled from each transmission signal and the decoupled portion of at least one transmission signal is divided into as many equal parts of equal strength and equal phase as reception paths present. These equal parts of the decoupled transmission signal portion are coupled into the respective reception paths and the strengths and phases of the equal parts transmitted over the respective reception paths (DP1, . . . ,DPN; Rx1, . . . ,RxN; AD1, . . . ,ADN) are measured. The transmission factors of all other ones transmission paths and reception paths are determined from known transmission factor values for them and the measured strengths and phases of the equal parts of the at least one transmission path.

Abstract: A support member for a measurement chamber, which measurement chamber surrounds a target of interest intersected by a line defined by focal points associated with the measurement chamber, and which chamber separates and extracts unwanted scattered signals from the measurement chamber, the measurement chamber including a chamber section having an interior defined by rotation of a nonlinear curve about the line, and first and second focusing elements which couple the scattered signals out of the chamber section, includes a surface for attaching at least one of the target of interest and a source generating signals scattered by the target of interest and a sting element which is coaxial with the line and which is coincident with one of the focal points. According to one aspect of the present invention, the source is attached to the surface and supported by a sting element which is defined a body of rotation about the line.

Abstract: A radar test system for testing a collision avoidance radar system. The radar test system includes circuitry to downconvert a signal from the collision avoidance radar to an intermediate frequency signal, to delay the intermediate frequency signal to simulate the delay of a return signal from an object located a particular distance from the collision avoidance radar system, and to upconvert and transmit the intermediate frequency signal back to the collision avoidance radar system to determine if the collision avoidance radar system provides accurate distance readings. The radar test system further couples the intermediate frequency signal to a spectrum analyzer. The spectrum analyzer can be used to determine if the collision avoidance radar system is operating within the 76-77 GHz frequency band allocated by the Federal Communications Commission (FCC). The radar test system further couples the intermediate frequency signal to a power meter.

Abstract: A low RCS measurement system includes a measurement chamber which surrounds a target of interest intersected by a line defined by focal points associated with the measurement chamber and which separates and extracts scattered signals from the measurement chamber system, the measurement chamber system including a chamber having an interior defined by rotation of a nonlinear curve about the line, and first and second focusing elements which couple the scattered signals out of the chamber, a signal source which emits signals along the line, wherein the emitted signals interact with the target of interest to thereby produce the undesirable scattered signals and desirable backscattered signals, a source support pylon which supports an output element of the source and which couples the scattered signals out of the chamber, and a target support pylon, which supports the target of interest at one of the focal points, and which is coaxial with the line.

Abstract: A Doppler-based radar system used in monitoring the speed of moving vehicles includes a self test circuit and related method for independently and remotely testing the operability of the entire radar system including the critical microwave components. The self test circuit includes a low frequency modulation diode positioned adjacent the antenna horn. The modulating diode causes a change in the voltage standing wave ratio seen by the radar system(s), thereby modulating the energy of the reflected radar test signal. The modulated test signal is compared to the original test signal and a resultant control signal is generated. The radar system is combined with a retarder system controller and a control system computer to provide an industrial control application, such as for controlling railway cars in a hump yard. Any number of additional radar systems/retarder system controllers can be added to expand the application.

Abstract: A high frequency signal, which is produced in a oscillator, is modulated by a frequency from a modulating signal generated by a modulation signal generator and radiated from a sending antenna. A reflected signal from a target object is received by a receiving antenna, and frequency-converted by a local oscillating signal from a directional coupler in the frequency convertor. Then, distance and speed information is detected by a signal processing unit. A modulator, which is connected to the oscillator, modulates the oscillator output in order to detect a failure. A detection unit, in which a filter unit, a rectification circuit, and a voltage comparison circuit are included, detects modulated elements originated in the above described modulator. The signal processing unit makes a failure determination based on the modulated elements which have already been detected.

Abstract: A self-implementing, self-diagnostic system for an anticipatory collision sensor system includes a transducer device for transmitting a modulated carrier signal and receiving the reflected modulated carrier signal from an object; a detection device for detecting a plurality of Doppler shifted harmonic components from the reflected modulated carrier signal; a range determining device responsive to the amplitude of at least two of the harmonic components for determining the instantaneous range of the object; a velocity measurement device, responsive to the frequency of at least one of the harmonic components, for determining the relative, instantaneous velocity of the object; an indicating device, responsive to at least one of the modulated carrier signal, the reflected modulated carrier signal, the amplitude, and the frequency, to indicate the condition of the system.

Abstract: A simulator for testing the performance accuracy or calibrating a collision avoidance radar system. The simulator includes circuitry for receiving a signal from the collision avoidance radar system and for generating a signal tracking the frequency of the radar system. Circuitry is further included in the simulator utilizing the tracking signal to generate a signal offset in frequency from the collision avoidance radar system output signal and to transmit the offset signal to the collision avoidance radar. The offset is controlled so that the collision avoidance radar should indicate an object is located a distance (D) away. Circuitry is further included in the simulator so that the offset has a first value when the radar system output is increasing in frequency and a second value when the radar system output is decreasing in frequency. The first and second offset values are controlled so that the radar system should indicate an object is moving at a rate (dD/dt) upon receiving the offset signal.

Abstract: A variable radar altimeter test system for providing a test of the altime portion of a flying object guidance system which simulates actual flight conditions includes an antenna connection to receive a signal from the flying object being tested, a synthesizer for generating a signal programmed to simulate data characteristic of a radar return signal, pulse modulation of the programmed signal to create a third signal which is returned to the flying object under test to stimulate the altimeter portion of its guidance system.