Abstract: A system and method for passively estimating range and angle of a source are disclosed. The source may be any wave source including radio-frequency (RF), optical, acoustic or seismic sources. In some RF embodiments, the system includes a single aperture antenna to simultaneously receive RF signals from the RF source through a plurality of sub-apertures, and a signal processor to perform a proximity test using samples simultaneously collected from the sub-apertures to determine whether or not to calculate angle and range estimates to the source based on either a curved wavefront assumption or a planar wavefront assumption.

Abstract: Probing incident radar fields in a target test zone of a RCS test facility by exploiting angular radar response of a long and uniform rigid body supported horizontally across or vertically through the test zone. The rigid body is free to rotate about the broadside condition. Thus, the angle of the rigid body is gradually changed with respect to the direction of arrival of the incident wave. Radar echo from the rigid body is measured as a function of the rigid body angle. The data is then processed to yield a profile of the incident wave intensity along the rigid body. By varying the azimuth angle continuously while recording radar data, the data may be processed by the fast Fourier transform (FFT) algorithm to yield a profile of the incident wave intensity along the rigid body.

Abstract: A system for testing radar in accordance with one embodiment comprising a target motion platform; a target motion platform controller for controlling motion of the platform; a radar responsive tag and a delay line located on the target motion platform; the radar which is being tested; and a motion measurement simulator for inputting data to the radar electronics assembly to simulate movement of the radar. In some embodiments the system further comprises a radar motion platform, wherein the radar electronics assembly is positioned on the radar motion platform; a radar motion platform controller for controlling the movement of the radar motion platform; and a master controller coupled to the radar motion platform controller and the target motion platform controller.

Abstract: This equipment is of the TCAS type. In order to improve its integrity and the reliability of its measurements, its computing unit is provided with a cross-checking function carrying out the comparison between two values of a same parameter, for example a relative distance with respect to an intruder, one of them generated by its own estimating means and the other communicated by another TCAS equipment installed on the intruding aircraft and generating a discordance alarm in the case of the observed difference exceeding a tolerance threshold. The computing unit is provided with fault locating means locating the aircraft whose TCAS is faulty when in the presence of several intruding aircraft, by examining the observed differences in pairs of values of a same parameter established for each intruding aircraft.

Abstract: Probing incident radar fields in a target test zone of a RCS test facility by exploiting angular radar response of a long and uniform rigid body supported horizontally across or vertically through the test zone. The rigid body is free to rotate about the broadside condition. Thus, the angle of the rigid body is gradually changed with respect to the direction of arrival of the incident wave. Radar echo from the rigid body is measured as a function of the rigid body angle. The data is then processed to yield a profile of the incident wave intensity along the rigid body. By varying the azimuth angle continuously while recording radar data, the data may be processed by the fast Fourier transform (FFT) algorithm to yield a profile of the incident wave intensity along the rigid body.

Abstract: A method for correcting bias in altimetry data for ascending satellite tracks and descending satellite tracks. For satellites operating in tandem, calculate ascending track bias between the height measurement made by the first and the second satellites for the ascending tracks in a region, calculate an ascending bias correction by least squares fitting a polynomial to the bias as a function of significant wave height for the ascending tracks, and apply a portion of the ascending track bias to the sea surface height measurements. The correction can be calculated based on only one track and its crossover points. Another embodiment uses data from only one satellite, estimates the sea state bias at the crossover points separately for the ascending and descending tracks, and apportions a percentage of the difference at the crossover points to the tracks based on minimizing the rms differences between the ascending and descending tracks.

Abstract: An automotive radar device that can securely detect dirt adhering to the surface of a vehicle-side radome irrespective of the positional relation between the vehicle-side radome and a radar. The automotive radar device has a radio-type radar housed in a vehicle-side radome installed on a vehicle, the radio-type radar including a transmitting unit and a receiving unit. The automotive radar device sends and receives radio waves from the radar through the vehicle-side radome and measures distance and relative velocity with respect to a subject. The automotive radar device includes a guiding unit that is arranged between the vehicle-side radome and the radar and that guides a reflected wave from adhering matter on a surface of the vehicle-side radome to the receiving unit of the radar, and an adhering matter judging unit that judges the existence/non-existence of the adhering matter on the surface of the vehicle-side radome on the basis of signal level of the reflected wave received by the receiving unit.

Abstract: The Ground Moving Target Indicator (GMTI) target detection accuracy test system receives, compares and analyzes GMTI test data that is formatted according to the NATO-EX (v.2.01) Standard. The GMTI target detection accuracy test system also uses Global Positioning System (GPS) data from the objective target and target reports generated by the GMTI sensor to display the simulation test results. At the conclusion of the GMTI sensor test, both the GPS and GMTI data are collected and compared using a computer processor and the results are displayed using the MATLAB® program to better indicate detection accuracy and provide a higher level of target detection accuracy. A method for testing artillery target detection accuracy method is also provided for characterizing the performance of any GMTI adhering to the NATO-EX Standard and testing against an objective target outfitted with GPS instrumentation.

Abstract: Array antenna calibration verification coupling interrogator and responder with mode-related interrogation signal having a previous calibration phase angle, producing in responder a characteristic interrogation response. Conjugate signal is generated by reversing phase of interrogation signal, producing in responder a characteristic conjugate response. Interrogation and conjugate responses sensed and combined to determine difference characteristic for responder array element. Responder difference characteristic iteratively determined for elements in antenna array representative of present calibration verification state. Present and previous calibration verification states compared, with significant variation adapting array to desired calibration verification state. Verification processor controls interrogator, responders, and signals providing built-in missile RADAR calibration verification.

Abstract: A method to control a track gate and a level gate in an altimeter tracking an altitude of an airborne vehicle comprising emitting signals, directed toward a terrain, from the airborne vehicle, receiving terrain echo signals, positioning the track gate to a selected reference amplitude on the rising edge of the terrain echo signals, positioning the level gate to within a selected range of the peak amplitude level of the terrain echo signals, measuring a change in a location of the peak amplitude between sequentially received terrain echo signals, and varying a separation between the track gate and the level gate based on the measured change in the location of the peak amplitude. The terrain echo signals comprise reflections of the emitted signals from the terrain, and each terrain echo signal has a rising edge and a peak amplitude.

Abstract: A system for dynamically compensating signal propagation for flexible radar antennas receives measurement signals indicating the position of selected locations of an antenna array. The future shape of the antenna array at a future time is predicted, and compensation signals are applied to signals generated or received by the antenna elements. The compensation signals are based on the future shape of the antenna array.

Abstract: A level measuring instrument has a variable transmitting power for measuring a filling level in a tank. The level measuring instrument includes a generator unit selectively generating different transmitting powers. The generator unit is controlled so that the transmitting power is respectively adapted to the corresponding environmental conditions. For this purpose, the generator unit has for instance two different oscillators, which are driven selectively.

Abstract: A radar includes a transmission section, a heterodyne reception section, a power supply section and a detection section. The transmission section emits a transmission wave to a target. The heterodyne reception section receives a reflected wave from the target. The power supply section supplies power to the reception section. A switching frequency of the power supply section is in synchronization with a local oscillation frequency of the reception section. The detection section determines that the switching frequency is out of synchronization with the local oscillation frequency when a certain peak frequency existing in an output signal of the reception section before a transmission state of the transmission section is changed still exists in the output signal of the reception section after the transmission state of the transmission section is changed.

Abstract: The present invention is a combined aircraft TCAS/Transponder with common antenna system and transmitter. Common TCAS/Transponder multi-monopole top and bottom antennas may be connected to a top and bottom antenna modules, the top and bottom antenna modules being electrically coupled to the combined TCAS/Transponder transmitter/receiver block through connection lines.

Abstract: A method for phase calibrating antennas in a radar system is disclosed. The method comprises providing a transmit antenna and two or more receive antennas, the receive antennas each in communication with a respective receiver channel. A radio frequency pulse having a leakage pulse is transmitted from the transmit antenna. The leakage pulse is received at each of the receive antennas and respective receiver channel. The relative phase change between the receive antennas is determined by using the leakage pulse as a reference signal.

Abstract: In a combined GPS/altimeter device, the calibration and hence the accuracy of barometric altimeter measurements are enhanced with the aid of derived altitudes from a GPS. The device determines the need for calibration and perform the subsequent computations necessary to facilitate the calibration. Furthermore, the device determines a correction quantity that should be applied to barometric altitude readings, thereby allowing the device to be calibrated while in motion. Both of these features ultimately result in a more accurate determination of altitude.

Abstract: The invention generally relates to the field of computer software particularly to an improved method of providing aircrew decision aids for use in determining the optimum placement of an Electronic Attack (EA) aircraft. The core of the invention is a software program that will dynamically provide the EA flight crew situational awareness regarding a threat emitter's coverage relative to the position of the EA aircraft and to the position of protected entities (PE). The software program generates information to provide visual cues representing a Jam Acceptability Region (JAR) contour and a Jam Assessment Strobe (JAS) for display via designated aircraft cockpit processors and devices. The JAR and JAS will aid the EA aircrew in assessing the effectiveness of a given jamming approach.

Abstract: While an FM-CW mode for sensing an object, in which a frequency of an electromagnetic wave transmitted from a transmission/reception antenna 6 is continuously modulated, and also, a CW mode for judging an abnormal condition, in which the frequency of the electromagnetic wave to be transmitted from the transmission/reception antenna 6 is not modulated are switched, an abnormal condition judging section judges an abnormal condition when a signal level of a reception signal of the FM-CW mode is smaller than, or equal to a first judging threshold value, and also, a signal level of a reception signal in the CW mode is smaller than, or equal to a second judging threshold value which is higher than the first judging threshold value.

Abstract: Methods are provided where: a signal is transmitted from an illuminating source and received cavity waveguides disposed on an object; a position and/or orientation of the object is determined based on the signal received in the waveguides; and data representing the determined position and/or orientation is transmitted to a remote location or generated for use in the object. The illuminating source can also be moved to indicate a change in a predetermined trajectory or target position where a new position and/or orientation of the object is determined based on the signal received in the waveguides and the object is controlled to change the predetermined trajectory or target position to the indicated new predetermined trajectory or new target position. A change can also be detected in the predetermined trajectory or target position and the object controlled to correct the change.

Abstract: A method of operating a multibeam radar carried on a platform flying a mission over a prescribed flight path to obtain images of a plurality of target areas, the beams of said radar being the result of respective transmit pulses and beam returns being received by respective receive windows. A range of pulse repetition frequencies and pulse repetition frequency change rates are used in an iterative process to determine non-collision alignments of any combination of transmit pulses and receive windows. When a non-collision alignment is determined the particular arrangement producing that non-collision alignment is used in a simulated flight of the platform to determine dwell time before a collision occurs. An arrangement that produces sufficient dwell time to accomplish a mission is then used in an actual flight of the platform.

Abstract: A method to compensate for variances in signal path delays for a plurality of radar return processing channels is described. The method comprises providing a signal in the signal path between an antenna and a corresponding receiver of each radar return processing channel, receiving a reflection of the provided signal from each antenna at the corresponding receiver, measuring phase variances between the reflected signals processed by each receiver, and adjusting compensation algorithms for each radar return processing channel based on the measured phase variances.

Abstract: A system and method for electromagnetic position determination utilizing a calibration process. For calibration, a transmitter is positioned at multiple locations in an area of interest and multiple receivers receive and record signal characteristics from the transmitter to generate a calibration data set. The unknown position of a transmitter may be determined by receiving signals from the transmitter by multiple receivers. A locator data set is generated based on the comparison between two received signal characteristics determined for each receiver. The locator data set is compared with the calibration data set to determine the unknown position. In one embodiment, the signal comparisons are the differences between electric and magnetic field phase. Further embodiments utilize signal amplitude differences. A reciprocal method utilizing a single receiver and multiple transmitter locations is disclosed.

Abstract: On/off timing of an amplifier and timing of antenna selection are accurately adjusted. When adjusting the on/off timing of the amplifier, modulation of a transmit signal is stopped, and a switch is set so as not to select any one of the antennas, thereby totally reflecting the transmit signal; in this condition, the timing is controlled so that the average value of the output level of a mixer becomes a minimum. When adjusting the antenna selection timing, modulation of the transmit signal is stopped, and a reflective object is placed in close proximity to the antenna; in this condition, the timing is adjusted so that the average value of the output level of the mixer becomes a maximum.

Abstract: A FM-CW radar system comprises a frequency modulated continuous wave digital generator that produces both in-phase (I) and quadrature-phase (Q) outputs to orthogonally oriented transmitter antennas. A linearly polarized beam is output from a switched antenna array that allows a variety of I-and-Q pairs of bowtie antennas to be alternately connected to the transmitter and receiver. The receiver inputs I-and-Q signals from another bowtie antenna in the array and mixes these with samples from the transmitter. Such synchronous detection produces I-and-Q beat frequency products that are sampled by dual analog-to-digital converters (ADC's). The digital samples receive four kinds of compensation, including frequency-and-phase, wiring delay, and fast Fourier transform (FFT). The compensated samples are then digitally converted by an FFT-unit into time-domain signals. Such can then be processed conventionally for range information to the target that has returned the FM-CW echo signal.

Abstract: An in-vehicle radar apparatus includes a beam emitting part that emits a beam, a casing that supports the beam emitting part, and a reference unit that is attached to the casing and is equipped with multiple surfaces usable as a reference plane. A surface of the casing to which the reference unit is attached and the reference plane form an angle that depends on which one of the multiple surfaces is used as the reference plane.

Abstract: The radar apparatus of the present invention can obtain distance to a target and speed with higher accuracy even when multiple targets are running within a detecting field of a radar. The radar apparatus can transmit a radio wave by alternately switching a section having a frequency slope and a section having no frequency slope with the radar for simultaneously transmitting a couple of frequencies having a frequency difference. Measurement of distance to the target and relative speed is conducted in the above two sections, results of measurement are compared with each other in the adjacent sections, and the result of measurement is determined correct only when there is no inconsistency in these measurement results.

Abstract: The method and system provide provisions for generating a respective detection state value associated with each of a plurality of RF receive beams. A first state value is indicative of a detection. The method and system further provide provisions, for each of the detection state values equal to the first state value, for generating a respective detection range value. The method and system further provide provisions for selecting one of the detection state values equal to the first state value and verifying the selected detection state value to provide one of a positive verification and a negative verification associated with the selected detection state value. The method and system further provide provisions for setting the selected detection state value to be equal to the second state value in response to a negative verification.

Abstract: An apparatus for use in controlling a simulated target position in a millimeter wave, hardware-in-the-loop system includes a pair of horns and a conditioning circuit. The conditioning circuit is capable of generating a pair of output millimeter wave signals, each to be broadcast from a respective one of the horns, the output millimeter wave signals being out of phase by a predetermined amount, and capable of attenuating at least one of the output millimeter wave signals to control the position of the simulated target in a first and a second region. A method for use in controlling a simulated target position in a millimeter wave, hardware-in-the-loop system includes generating a pair of output millimeter wave signals that are out of phase by a predetermined amount; attenuating at least one of the output millimeter wave signals to control the position of the simulated target in a first and a second region; and broadcasting the millimeter wave signals.

Abstract: A system for testing radar in accordance with one embodiment comprising a target motion platform; a target motion platform controller for controlling motion of the platform; a radar responsive tag and a delay line located on the target motion platform; the radar which is being tested; and a motion measurement simulator for inputting data to the radar electronics assembly to simulate movement of the radar. In some embodiments the system further comprises a radar motion platform, wherein the radar electronics assembly is positioned on the radar motion platform; a radar motion platform controller for controlling the movement of the radar motion platform; and a master controller coupled to the radar motion platform controller and the target motion platform controller.

Abstract: An apparatus for use in controlling a simulated target position in a millimeter wave, hardware-in-the-loop system includes a pair of horns and a conditioning circuit. The conditioning circuit is capable of generating a pair of output millimeter wave signals, each to be broadcast from a respective one of the horns, the output millimeter wave signals being out of phase by a predetermined amount, and capable of attenuating at least one of the output millimeter wave signals to control the position of the simulated target in a first and a second region. A method for use in controlling a simulated target position in a millimeter wave, hardware-in-the-loop system includes generating a pair of output millimeter wave signals that are out of phase by a predetermined amount; attenuating at least one of the output millimeter wave signals to control the position of the simulated target in a first and a second region; and broadcasting the millimeter wave signals.

Abstract: Systems and techniques for coherent combining radars include generating a phase and range calibration and initialization values for adjusting a time delay and a phase of a transmitted pulse from one of the radars, resulting in received composite target echoes at each of the radars having contributions from monostatic and bistatic echoes. The method further includes predicting phase and range correction values for further adjusting the time delay and the phase of subsequent radar pulses transmitted by one of the radars to continue to result in received composite target echoes at each of the radars. The method further includes coherently summing the composite target echoes.

Abstract: A system and method is provided for detecting emitter signals and for determining a scan strategy for a receiver system that receives such emitter signals. Once a scan strategy is computed, it may be desirable to evaluate the scan strategy's intercept performance against a given emitter set under specific altitude, range and receiver load conditions. 2D and 3D emitter scan patterns are modeled and simulated. The receiver scan is also modeled and simulated. Performance statistics from the simulation are collected and analyzed.

Abstract: Provided are a radar system and a contamination judging method capable of reducing adjustment costs and detecting contamination adhering to a radome with accuracy. The radar system includes an antenna for transmitting a transmission wave in a plurality of different directions and for receiving a reflected wave, a radome for protecting the antenna, and a signal processing unit for calculating a distance to an object based on the transmission wave and the reflected wave, in which the radome has a metallic reflecting section provided in a predetermined direction with respect to the antenna, the signal processing unit has a contamination judging unit which calculates a deviation between a reception level of the reflected wave from the reflecting section in the predetermined direction and a reception level of the reflected wave from directions other than the predetermined direction and judges contamination adhering to the radome based on the deviation.

Abstract: A method and system for determining a product level in a tank which determine a first level measure using emission of electromagnetic waves into the tank, detect a differential pressure, determine an observed density based on the detected differential pressure and the first level measure, and determine a second level measure based on the observed density and a currently measured differential pressure. The present invention is based on the realization that a level measurement based on differential pressure and an observed density can provide a valuable redundant level measurement, which can provide increased reliability and enable detection of errors.

Abstract: A rocket tube for housing a reloadable rocket motor is connected to a spacer element and a wire-rider element. A sensor target for reflecting radar signals is screwably attached to the rocket tube. The sensor target is provided with a plug for effectively sealing one end of the rocket tube with the other end of the rocket tube being utilized to reload a rocket motor upon completion of a test firing. A guide wire is threaded through the wire-rider element with the guide wire serving as a travel path. The rocket tube, spacer element, and wire-rider element are connected in an easily assembled, aerodynamic manner that allows for multiple radar tests using the same components within a brief time period.

Abstract: A method (for example, machine-implemented, e.g., via a receiver), for determining whether a transmitted pulsed-signal is a linear or non-linear frequency modulated (FM) signal, includes: iteratively determining upper and lower bound slopes associated with frequency components of a pulse of a signal during a time period of the pulse; and comparing each determined upper bound slope to a previous or initial upper bound reference slope and comparing each determined lower bound slope to a previous or initial lower bound reference slope in order to determine the linearity, or non-linearity, of the signal.

Abstract: A system for tracking an object in space for position, comprises a transponder device connectable to the object. The transponder device has one or several transponder aerial(s) and a transponder circuit connected to the transponder aerial for receiving an RF signal through the transponder aerial. The transponder device adds a known delay to the RF signal thereby producing an RF response for transmitting through the transponder aerial. A transmitter is connected to a first aerial for transmitting the RF signal through a first aerial. A receiver is connected to the first, a second and third aerials for receiving the RF response of the transponder device therethrough. A position calculator is associated to the transmitter and the receiver for calculating a position of the object as a function of the known delay and the time period between the emission of the RF signal and the reception of the RF response from the first, second and third aerials. A method is also provided.

Abstract: A test device for a frequency modulated continuous wave (FMCW) radar is provided. The test device has a central control unit for monitoring the FMCW radar. When the FMCW radar transmits a frequency modulated continuous signal to search for a target, the central control unit of the test device in present invention will simulate the motion of the target according to a plurality of setting parameters and generate an echo signal to the FMCW radar. The present invention also includes a first digital signal synthesizer and a transmitting unit. The first digital signal synthesizer is coupled to the central control unit for generating and transmitting an intermediate-frequency signal to the transmitting unit according to the settings in the central control unit and a reference clock. The transmitting unit generates the echo signal according to the intermediate-frequency signal.

Abstract: A first receiving antenna having a broad antenna characteristic and a second receiving antenna having a narrow antenna characteristic are provided in a radar sensor utilizing the pulse-echo principle. A switching between the receive signals of both receiving antennas at the clock pulse of the pulse repetition frequency of the transmitted radar pulses takes place in the receiving path.

Abstract: A system and method for passively estimating range and angle of a source are disclosed. The source may be any wave source including radio-frequency (RF), optical, acoustic or seismic sources. In some RF embodiments, the system includes a single aperture antenna to simultaneously receive RF signals from the RF source through a plurality of sub-apertures, and a signal processor to perform a proximity test using samples simultaneously collected from the sub-apertures to determine whether or not to calculate angle and range estimates to the source based on either a curved wavefront assumption or a planar wavefront assumption.

Abstract: The present invention relates to a method for calibrating the phase of a microwave source, in which: a calibration circuit is closed, the calibration circuit comprising an injection channel connected to a measurement channel via the source to be calibrated; a test signal is injected through the source to be calibrated, the test signal being injected on the injection channel, the phase ?m of the signal having passed through the source to be calibrated is measured, the phase of the signal being measured on the measurement channel, wherein: the amplitude Am of the signal having passed through the source to be calibrated is measured, the amplitude of the signal being measured on the measurement channel; The calibration circuit is opened at the source to be calibrated; the test signal is injected on the injection channel; the phase ?f and the amplitude Af of the signal present on the measurement channel is measured; a corrected phase value ?c is determined, this corrected phase being the phase of a complex number

Abstract: Provided is a RAM check unit capable of checking a RAM included in a radar system even when the radar system is in operation. An LSI instructs a high-frequency unit to output a radar-transmitted signal. When a radar-received signal is received from the high-frequency unit, calculation is performed based on the signal. The result of the calculation is transferred to a CPU. The CPU transmits a calculated distance to the outside. When a processing end sensing unit included in the LSI senses termination of radar-received signal processing, an RAM check unit initiates RAM check. When the RAM check is terminated, the high-frequency unit is instructed to output a radar-transmitted signal. Consequently, the RAM check is performed during a period between pieces of radar-received signal processing during which a load on the LSI is light. Thus, the RAM check can be performed even when the radar system is in operation.

Abstract: A power supply apparatus controls the gate and drain power supplies at the rise time so that an output voltage of the gate power rises earlier than that of the drain power supply. Another power supply control apparatus controls the gate and drain power supplies at the fall time so that an output voltage of the gate power supply fails later than that of the drain power supply. Another power supply control apparatus turns off the drain supply of the FET among power supplies when it is detected by a voltage monitor whenever either of output voltages or the power supplies are not within said specified range.

Abstract: A radar acquires a formed SAR image of radar scatterers in an area around a central reference point (CRP). Target(s) are within the area illuminated by the radar. The area covers terrain having a plurality of elevations. The radar is on a moving platform, where the moving platform is moving along an actual path. The actual path is displaced from an ideal SAR image acquisition path. The radar has a computer that divides the digital returns descriptive of the formed SAR image into multiple blocks, such as a first strip and an adjacent strip. The first strip is conveniently chosen, likely to generally align with a part of the area, at a first elevation. An adjacent strip covers a second part of the area at a second elevation. The first strip is overlapping the adjacent strip over an overlap portion. The first and second elevation are extracted from a terrain elevation database (DTED).

Abstract: If the maximum time width Lt of the intensity of received light of reflected waves from a vehicle ahead is smaller than a reference time width, it is judged that the vehicle ahead is positioned in proximity to the detection limit distance of an obstacle detection device for vehicle. Thus, there is no problem, for example, even if a cut-in vehicle is present in reality between the vehicle ahead and the vehicle of interest and nevertheless, the distance to the cut-in vehicle cannot be detected. It can be judged whether the vehicle ahead is positioned in proximity to the detection limit distance of the device by judging the magnitude relation between Lt and the reference time width. As a result, the detecting capability of the device can be judged with accuracy.

Abstract: An improved method for determining whether a measurement point, measured using a differential absorption LIDAR (DIAL) system, represents a plume point or a non-plume point. Concentration path lengths (CPL's) for a plurality of measurement points are determined. An average non-plume CPL, CPL, is provided. For each measurement point, a standard deviation, CPLsd, is calculated based on first order error propagation and it is determined that the measurement point represents a non-plume point when the Hooshmand decision rule (HDR) is met. The HDR is given by, ( cpl - CPL _ CPL sd ) 2 > ( T ) 2 , where cpl is the corresponding CPL of the measurement point being tested and T is a threshold standard deviation level.

Abstract: A Quadrature Error Corrected Digital Waveform Synthesizer (QECDWS) employs frequency dependent phase error corrections to, in effect, pre-distort the phase characteristic of the chirp to compensate for the frequency dependent phase nonlinearity of the RF and microwave subsystem. In addition, the QECDWS can employ frequency dependent correction vectors to the quadrature amplitude and phase of the synthesized output. The quadrature corrections cancel the radars' quadrature upconverter (mixer) errors to null the unwanted spectral image. A result is the direct generation of an RF waveform, which has a theoretical chirp bandwidth equal to the QECDWS clock frequency (1 to 1.2 GHz) with the high Spurious Free Dynamic Range (SFDR) necessary for high dynamic range radar systems such as SAR. To correct for the problematic upconverter local oscillator (LO) leakage, precision DC offsets can be applied over the chirped pulse using a pseudo-random noise dither.

Abstract: A vehicle control apparatus includes an obstruction detection unit for measuring a headway distance until an obstruction existing ahead of the vehicle by means of a radar device, a unit for performing vehicle control or alarm control on the basis of the headway distance, a unit for detecting detection performance of the obstruction detection means in a vehicle in which the obstruction detection unit is used to perform two or more controls containing the vehicle control or alarm control, and a unit for controlling to stop operation of the vehicle control or alarm control in accordance with the detection performance individually.

Abstract: The present invention relates to an avoidance system and method for directing an aircraft away from an exclusion zone. The exclusion zone may be any three dimensional space for example about a building or city. The avoidance system uses a constant signal from a ground based transmitter and an aircraft's receiver which receives and processes the signal and activates the avoidance system by engaging the flight director system or autopilot to steer away from the exclusion zone.

Abstract: A diagnostic method for a blind-zone sensing system including leading and trailing passive IR sensors periodically determines a separation distance between coverage areas of the leading and trailing sensors to diagnose sensor alignment. Signals produced by the leading and trailing sensors are sampled and stored over a defined interval of time for processing. A condition in which the sensor coverage areas abruptly encounter a stationary region of cooler temperature is detected when corresponding signal deflections are identified. The elapsed time between the identified signal deflections is measured and used along with an accurate measure of the vehicle speed to compute the separation distance between coverage areas of the leading and trailing sensors.