Abstract: A detection system (1) having an optical sensor (3), a radar device (2) and a signal processor (4) communicatively connected with the optical sensor and the radar device. The signal processor comprises: a first detector (41, 410-413) for detecting a first object on the basis of a first signal coming from the optical sensor and determining at least one first property of the first object; a second detector (42, 420-421) for detecting a second object on the basis of a second signal coming from the radar device and determining at least one second property of that second object, and a signaling unit (43) for producing a signal if the at least one first property and the at least one second property satisfy a predetermined condition.

Abstract: An electronic scanning radar apparatus has a cutting portion for cutting receiving data which is comprised of N numbers of data for each channel into two more short time data having M (<N) numbers of data in a time direction for each channel, an inverse matrix estimator for computing and estimating an inverse matrix of the time series correlation matrix from the short time data, and a phase information producing portion for computing CAPON phase information out of the estimated inverse matrix of the time series correlation matrix in order to detect a distance, an azimuth and a relative speed of a target on the basis of a computed CAPON phase information.

Abstract: A radar system transmits a beam of detection radio waves with a predetermined azimuth width, receives a reflected wave from a target, changes a central azimuth of the beam, and detects the distribution of reception signal strengths at predetermined angular intervals and for each predetermined distance. Then, when the reception signal strength distribution associated with changes in azimuth is expressed in rectangular coordinates, an azimuth corresponding to a vertex of an isosceles triangle that approximates the reception signal strength distribution and has an azimuth width, which is determined by the beam azimuth width, as its base is detected as the central azimuth of the target.

Abstract: A target detecting apparatus mounted on a vehicle has an electronically agile radar detecting a beat signal indicating a difference in frequency between transmission and reception signals and producing a time series of N reception data from the beat signal, a determining unit determining search areas placed at different ranges of distance from the vehicle while considering a running state of the vehicle and determining a data length for each search area, an extracting unit extracting (N?M+1) time series of short time data, respectively, having the data length corresponding to M reception data from the N reception data for each search area, a producing unit producing phase information from the short time data for each search area, and a detecting unit determining a target distance and a target bearing from the phase information and detecting a target from the target distance and the target bearing.

Abstract: Methods, systems and devices are disclosed for positioning an antenna having a sub-reflector assembly. A conical scan processor receives a period for a reference time pulse and a time tag. The processor calculates a rotation angle of the sub-reflector assembly using the received period for the reference time pulse and the received time tag. The processor may also receive a power measurement associated with the time tag. The processor may calculate and then output antenna boresight errors based on the calculated rotation angle of the sub-reflector assembly and the power measurements associated with the time tag.

Abstract: An aircraft radar system includes a radar antenna and a processing device. The processing device receives returns from the radar antenna associated with the scan. The processing device uses the returns from the scan for use in both incursion detection and weather phenomenon detection. A method for using the returns from the scan for both incursion detection and weather phenomenon detection is also disclosed.

Abstract: A target position is estimated in such a manner to maintain target position continuity, with high accuracy, even when the X coordinate displacement of the target is large. On a scan in which the target position is not detected, when a trajectory of the target in the past is within a predetermined region in the vicinity of the Y-axis, a position for estimate is a position having an X coordinate resulting from shifting, by a first displacement, the X coordinate estimated according to the trajectory, on a basis of the X coordinate of a previous position, while when the trajectory is not within the predetermined region, the position for estimate is a position having an X coordinate resulting from shifting, by a second displacement that is larger than the first displacement, the X coordinate estimated according to the trajectory, on a basis of the X coordinate of a previous position.

Abstract: Embodiments of the invention are concerned with a radar system, and relates specifically to scanning radar systems that are suitable for detecting and monitoring ground-based targets.

Abstract: An array antenna includes a first end portion that has a first plurality of antennas arranged with a spacing d therebetween and a second end portion that has a second plurality of antennas arranged with the spacing d therebetween. In the array antenna, a spacing between respective antennas in both the first and second end portions and are closest to a central portion is set to 2d, which is a value obtained from multiplying 2, which is the number of the antennas constituting each of both end portions, by the spacing d for both end portions. The antennas in the antenna array are continuously selected as a transmitting antenna by switching, and continuously emit transmission signals. The antennas in the antenna array are also successively selected as a receiving antenna by switching. In this way, by switching between transmission and reception of the antennas of the antenna array, nine reception channels CH1 through CH9 that are arranged with a uniform phase difference therebetween are obtained.

Abstract: An apparatus for measuring at least one of unintentional and intentional electromagnetic emissions for at least one of enabling electromagnetic location of predetermined electronic equipment giving off such at least one of such unintentional and intentional electromagnetic emissions, tagging such predetermined electronic equipment and tracking such predetermined electronic equipment and various combination thereof. The apparatus comprises an emitter mechanism for providing an amplified electromagnetic energy which at least one of amplifies and changes a frequency content of the at least one of such unintentional and intentional electromagnetic emissions signature of a targeted electronic device by using an applied electromagnetic field generated by the emitter mechanism. There is a receiver for receiving the at least one of such unintentional and intentional electromagnetic emissions signature of such targeted electronic device.

Abstract: A radar device has a long range radar sensor having a first transmission and receiving section for transmitting and receiving radio wave to a first detection range and a first signal processing section for detecting an object existing in the first detection range; a short range radar sensor having a second transmission and receiving section for transmitting and receiving a radio wave to a second detection range of which width is wider and of which distance is shorter than the first detection range and a second signal processing section for detecting an object existing in the second detection range; and a processing section for integrating information supplied from the first and second signal processing sections. And one of the long range radar sensor and the short range radar sensor stops a detection operation of the object to an overlapped range of both the detection ranges.

Abstract: A radar system array antenna includes plural elements. Each element is coupled to a port of a transmit-receive device. Digital data representing the characteristics of the radar signal is applied to a monolithic IC combination DAC/ADC, which converts the digital data into analog transmit signal. The analog transmit signal is applied to a monolithic microwave IC transceiver, which may be monolithic with the DAC/ADC. The transceiver upconverts the transmit signal. The upconverted transmit signal is applied to a transmit port of the transmit-receive device and transmitted. Receive RF signal is coupled from each antenna element through the transmit-receive device to a receive signal port of the transceiver. The transceiver downconverts the receive signal to produce received downconverted signal. The downconverted signal is coupled to the ADC part of the DAC/ADC, which converts to receive digital signal. Digital processing processes the receive digital signal to produce the return target information.

Abstract: A radar apparatus wherein transmission beams are set such that reception intensities corresponding to the transmission beams are gradually reduced from a center direction toward an edge direction of a scanning-angle range. For example, when a vehicle serving as a target is located in the center direction of a transmission beam, the reception-signal intensity corresponding to an adjacent transmission beam is set higher than the reception intensity in the center direction corresponding to the transmission beam. When the scanning-angle distributions of reception-signal intensities corresponding to transmission beams are detected, a scanning angle exhibiting a peak reception-signal intensity is nearer the center of the scanning-angle range than the azimuth angle at which the target is actually located. Thus, a peak reception-signal intensity corresponding to a target located in a region that is a predetermined amount outside the scanning-angle range of a transmission beam appears inside the scanning-angle range.

Abstract: System for obtaining information about a vehicle or a component therein includes sensors arranged to generate and transmit a signal upon receipt and detection of a radio frequency (RF) signal and a multi-element, switchable directional antenna array. Each antenna element is directed toward a respective sensor and transmitter RF signals toward that sensor and receive return signals therefrom. A control mechanism controls transmission of the RF signals from the antenna elements, e.g., causes the antenna elements to be alternately switched on in order to sequentially transmit the RF signals and receive the return signals from the sensors or cause the antenna elements to transmit the RF signals simultaneously and space the return signals from the sensors via a delay line in circuitry from each antenna element such that each return signal is spaced in time in a known manner without requiring switching of the antenna elements.

Abstract: A scanning method of an in-vehicle scanning-type radar for emitting beams subsequently to execute scanning and for detecting an object includes determining whether or not the object is in an approaching state. When it is determined that the object is not in the approaching state, executed is a first scanning for scanning within a first angle range. When it is determined that the object is in the approaching state, executed is a second scanning for scanning within a second angle range that is narrower than the first angle. A period during which the radar scans the second angle range once in the second scanning is shorter than that during which the radar scans the first angle range once in the first scanning.

Abstract: A system is for recognizing obstructions and monitoring movements on or above an airport area (1) with sensors (2, 3, 4). A sensor (2) is a radar device having a plurality of antenna elements (12, 14), which are affixed to a curved surface (15) of an antenna carrier (2a) and are turned on, one after the other, in terms of time. Thus a first part of the antenna elements (14) is disposed on a first circular line (13) on the surface of the antenna carrier (2a), and a second part of the antenna elements (12) is disposed on a circular line (15) perpendicular to the first circular line (13). Therefore the data of the radar device (2) are evaluated in a first ROSAR process, to image the situation on the ground, and in a second ROSAR process, to image the heights of the flying objects to be observed.

Abstract: A system for differentiating between a signal from a physical source and a nonlinear signal effect includes an array, a delay control element and a signal processing element. The array is configured to detect a signal at a particular location using an initial time delay. The delay control element is configured to modify the initial time delay by a selected value and to apply a phase delay in an amount equal to the selected value and at a frequency of the signal. The signal processing element is configured to determine whether the signal corresponds to one of a physical source or a nonlinear signal effect based on whether a shift in a perceived location of the signal occurs.

Abstract: Systems and techniques for parallel demodulation and searching using an adaptive antenna array with a processor configured to control the adaptive antenna to search for a first signal with the first beam and to receive a second signal for demodulation with a second beam.

Abstract: A system and method for an electronically scanned antenna is provided in which phase shifters are deposited en masse along with other electronically scanned antenna components on a wafer scale substrate using a thin film process. Alternative wafer scale sizes may be utilized to furnish a required antenna aperture area. Significant processing costs for radar and communication systems are saved utilizing the present invention as compared with contemporary discrete phase shifters that are individually mounted on an antenna. In an aspect, the phase shifter is made up of a base electrode, a barium strontanate titanate (BST) ferroelectric varactor and a top electrode. The BST ferroelectric material is a voltage variable dielectric, which generates a radiation phase. The radiation phase is regulated by a phase shifter control. The radiation phase generates an electromagnetic field about a radiating element and electromagnetic radio waves are radiated from the radiating element.

Abstract: A concept is described for broadening the beam of a phased array radar antenna to provide continuous illumination of all radar targets within the search space, and this beam is compressed upon reception to realize the angular resolution that is possible with the antenna. The process is analogous to pulse compression. The advantages of the long dwell times provided by this concept include superior clutter suppression performance, more accurate tracking of targets, and the ability to analyze the target returns for reliable discrimination, classification and identification. The broad beam also reduces the power seen by an intercept receiver, for increased covert operation. This is all accomplished without any sacrifice in power. Various embodiments are disclosed.

Abstract: The present invention relates to a radar apparatus that forms multiple digital beams based on reflected waves of a transmitted radio wave. A transmit signal is transmitted in a predetermined cycle from one of transmitting/receiving antennas A1 to A4 arrayed in a row. The antennas A1 to A4, each switched between transmission and reception, are arranged such that the ratio of the spacing between one pair of adjacent antennas to the spacing between the other pair of adjacent antennas is 1:2. The reflected waves are received by the respective antennas, and DBF is performed based on the resulting received signals. Eleven-channel DBF is achieved using the four antennas with a space equivalent to six antennas. By achieving multiple channels with a minimum number of antennas, the size and cost of the apparatus can be reduced while also reducing the processing time and thus enhancing the performance.

Abstract: A radar system having a processor, a waveform generator, a plurality of antenna interfaces, a set of first antennas configured to transmit a waveform, and a set of second antennas configured to receive a reflected waveform is disclosed. The waveform generator and antenna interfaces are in control and signal communication with the processor, each of the first antennas are in signal communication with one of each antenna interface, and each of the second antennas are in signal communication with one of each antenna interface. The waveform generator is in control and signal communication with each antenna interface, and is configurable to generate a waveform conforming to at least two ISM bands. Each first antenna is configured to transmit a circularly polarized electromagnetic waveform, and each second antenna is configured to receive a reflected circularly polarized electromagnetic waveform complementary to the first antennas.

Abstract: A method and apparatus for generating accurate estimates of a radar target's azimuth and elevation angles for a phased-phased array rotating radar. Scan modulated coherently integrated (SMCI) monopulse curves are generated from a measured one-way transmit antenna pattern and three receive antenna patterns. The SMCI monopulse curves are calculated in advance for the expected beam steers. To utilize the SMCI monopulse curves, two-way Sum, Delta-Azimuth and Delta-Elevation target returns are coherently integrated, the target's monopulse ratios calculated, and the SMCI monopulse curves or polynomials used to calculate the target's U-offset and V-offset sine-space angles, which are added to the radar's beam steer to get an improved estimate of the target's sine-space angular position denoted as Utgt and Vtgt. A coordinate system transformation transforms Utgt and Vtgt to azimuth and elevation angles in a non-rotating coordinate system.

Abstract: A radar can detect target azimuths located outside and adjacent to a scanning angular range of a beam by determining changes in received signal strength (a signal-strength profile) in the azimuthal direction as a function of a beam azimuth in a predetermined scanning angular range, and estimating the target azimuth causing the signal-strength profile from the signal-strength profile, which is portion of a convex located adjacent to the outermost angle in the scanning angular range. For example, the target azimuth is estimated by a ratio between the received signal strength at the outermost angle of about 10.0° and the received signal strength at about 9.5°, which is one beam inside the outermost position.

Abstract: The present invention provides an electric wave axis adjusting apparatus for an on-vehicle radar capable of readily and precisely adjusting an electric wave axis only by making the scanning range and a detection range identical to each other and changing a scanning range, and of adjusting the electric wave axis of an on-vehicle radar without wasting time in order to detect a reflector.

Abstract: A radar apparatus comprises: a transmitter unit having a high-frequency oscillating unit whose oscillation frequency is variable, and a pulse amplitude modulating unit for amplitude-modulating a pulse of a transmission high-frequency signal output from the high-frequency oscillating unit with a first control pulse signal; a receiver unit having a gating unit for controlling ON/OFF of an input of a received high-frequency signal with a second control pulse signal; and a controlling and signal processing unit for controlling the transmitter unit and the receiver unit, and for switching a first operation mode for making the apparatus function as an FM-CW radar, and a second operation mode for making the apparatus function as a pulse radar.

Abstract: An ultra wideband radar system for detecting moving objects comprising an antenna, which may be scanned in at least one dimension, and a signal processor wherein the signal processor includes a scan combiner that combines scan information in accordance with a candidate trajectory for the moving object. Scans may be combined by integration or filtering. A fast calculation method is described wherein the scans are combined into subsets and subsets are shifted in accordance with the candidate trajectory before further combination. A method is described wherein a region is scanned with an ultra wideband radar, the scan information is combined in accordance with an expected trajectory to enhance the object signal to noise. Further features are described wherein the scan information is combined according to a family of trajectories. A trajectory yielding a potential object detection initiates a further scan combination step wherein the family of trajectories is further resolved.

Abstract: An automotive radar which can process signals at high speed to detect a target in a wide angle range is provided. The automotive radar comprises a transmitting antenna which emits an electromagnetic wave, two receiving antennas which receive the electromagnetic wave reflected by a target, an antenna plate on which the transmitting antenna and two receiving antennas are arranged. It also includes a drive which rotates the antenna plate in an azimuth direction, which corresponds to the direction of arrangement of the two receiving antennas, to scan a detection angle formed by the two receiving antennas. The drive has rest time between scans to stop rotation. The automotive radar also includes a signal processor which detects the azimuth angle of the target with respect to a reference direction during the rest time according to received signals from the two receiving antennas and the rotation angle of the antenna plate at rest.

Abstract: A radar system with a radar sensor (10) which comprises a transmitting module (20), a receiving module (22) and a supply network (64), wherein the transmitting module (20) comprises a first plurality of partial antennas (26, 28, 30, 32, 34) and the receiving module (22) comprises a second plurality of partial antennas (46, 48, 50), and wherein the supply network (64) operates at least one partial antenna (30) of the transmitting module (20) together with at least one partial antenna (48) of the receiving module (22) in a first operating mode, to obtain a first, low angular resolution, and wherein the supply network operates one group of partial antennas (26, 28, 30, 32, 34) of the transmitting module (20) together with a group of partial antennas (46, 48, 50) of the receiving module (22) in a second operating mode to obtain a second high angular resolution.

Abstract: Methods, apparatus, and computer program products are provided for tracking at least one moving target with a radar device without requiring the use of Doppler information. The invention comprises scanning an area with radar signals at a first time to receive a first plurality of target data signals indicative of a position of the target at the first time and determining the position of the target at the first time by collecting the first plurality of target data signals into a first target data grouping, such that the first target data grouping defines a first reference point. Similarly, a second reference point for the target is determined for a second time, and the position of the first reference point is compared to the position of the second reference point to track the moving target. Advantageously, the tracked positions of the moving target may be used to predict a future position of the target at a subsequent time.

Abstract: An active protection system comprising an ultrawideband radar for threat detection, an optical tracker for precision threat position measurement, and a high powered laser for threat kill or mitigation. The uwb radar may use a sparse array antenna and may also utilize Doppler radar information. The high powered laser may be of the optically pumped solid state type and in one embodiment may share optics with the optical tracker. In one embodiment, the UWB radar is used to focus the high power laser. Alternative interceptor type kill mechanisms are disclosed. In a further embodiment, the kill mechanism may be directed to the source of the threat.

Abstract: A method and apparatus for estimating elevation angle when using a broad search beam such as a cosecant-squared beam is provided. The range of a target detected during a search with a broad beam covering a broad angular search area is determined. Based on the determined range, consecutive beams are transmitted at increasing search elevation angles in the broad angular search area. Echo signals of the consecutive beams are used to determine an elevation angle estimate for the target.

Abstract: A plurality of primary detection regions A to I are scanned by switching a beam width and a beam direction of an antenna. The primary detection regions A to I are formed such that one detection region overlaps at least one of other detection regions. A small region (any one of secondary detection region (1) to (14)) corresponding to a region provided by excluding a region corresponding to a sum of set of the detection regions where a detection object was not detected, from a region corresponding to a product set of the primary detection regions where the object was detected is specified as a bearing in which the object exists, based on detection results of the respective primary detection regions.

Abstract: The present invention is a wide band GaAs microwave monolithic integrated circuit (MMIC) transmit chip that is capable of transmitting linearly or circularly polarized signals when connected to a pair of orthogonal cross-polarized antennas. In an active phased-array antenna environment, this transmit chip is capable of transmitting signals with different scan angles. This invention also contains a digital serial to parallel converter that uses TTL signal to control the phase shifter and attenuator circuits that are required for controlling the polarization and scan angle of the transmitted signal.

Abstract: A method for dynamically verifying a multiple beam antenna placed on a craft including a device for determining the position and course of the craft and a transmitter that via the antenna can emit pulsed signals. At least two transponders are placed in different directions round a measuring area with each transponder receiving a pulsed signal of at least one frequency, different for the different transponders, from the antenna. The transponders are adapted to send, after receiving the pulsed signal, a corresponding pulsed signal to the measuring station in such a manner that the transponder sending the signal can be determined at the measuring station which evaluates how well the antenna has managed to direct the radiated energy in the desired directions.

Abstract: Methods, apparatus, and computer program products are provided for improving the crossrange resolution of a radar device for more accurate determinations of angular position of a target. The radar device transmits and receives scanning signals at crossrange beam positions having a beamwidth, wherein the beam positions are separated by a step. The radar device scans a target to receive target data from at least three beam positions, typically consecutive beam positions, to determine a first beam position with a first target data value that is greater than a second target data value of a second beam position preceding the first beam position and greater than a third target data value of a third beam position following the first beam position. A target data relationship between the first, second, and third beam positions is determined to provide the angular position of the target relative to the first beam position.

Abstract: Beams are irradiated in three directions by switching an irradiation direction of a mainlobe of an antenna by stages, and an echo is received from a detection object obtained in the mainlobe or a sidelobe in each irradiation direction. Then, reflection power intensity in each irradiation direction is found from the received echo, and pattern of relative variation of the reflection power intensity (power intensity pattern) in each irradiation direction is generated. Meanwhile, a detection region is divided into seven bearings “c” to “i” and a power intensity pattern when an object exists in each bearing is previously stored as a reference pattern in each bearing. Then, the bearing in which the detection object exists is specified by comparing the power intensity pattern obtained from the received echo with the reference pattern in each bearing.

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. In one embodiment of the invention, a set of models is used to compute antenna characteristics as a function of frequency, gain, power, beam width, scan and polarization. Data such as actual antenna gain vs azimuth for several polarizations may also be used, thereby reducing the amount of data needed for the antenna modeling purposes.

Abstract: A mobile communication base station determines the oncoming direction of a radio wave with a simple arrangement and transmits a narrow angle beam in this direction. Received signals from a pair of wide angle beam antennae 21-1 and 21-2 having an equal configuration and a common orientation and which are located close to each other are fed to a direction finder receiver 22 and a communication receiver 15. By utilizing the fact that the both received signals have a coincident amplitude, a phase difference between the received signals is detected. The oncoming direction of the received radio wave (or the direction of a mobile station) is determined on the basis of the phase difference. A beam switcher 12 is controlled so as to connect a transmitter 13 to a narrow angle beam antenna (one of 11-1 to 11-4) which is directed in the oncoming direction thus determined.

Abstract: A method that can locate the center of a target even when the target is a large vehicle, and that, when a plurality of beams are reflected, determines whether the reflected beams are from the same target or not, wherein, of peaks generated based on a radar signal reflected from the target, peaks whose frequencies are substantially the same and whose reception levels are not smaller than a predetermined value are selected and, when a plurality of such peaks are selected, a center angle between the angles of the leftmost and rightmost peaks is obtained, and the thus obtained center angle is taken as an angle representing the target. Further, the plurality of peaks are paired up to detect a distance, relative velocity, and displacement length for each of reflecting points on the target, and when the differences in these values are all within respectively predetermined values, the plurality of peaks are determined as being peaks representing the same target.

Abstract: A radar performs accurate and appropriate pairing even if peaks of approximately identical signal intensities or even if a plurality of peak groups having identical representative beam bearings exist in the frequency spectrum. First, the peak frequency of a peak which appears in the frequency spectrum is determined for each of an up-modulating interval and a down-modulating interval in predetermined beam bearings, and signal-intensity profiles in the beam bearings are extracted with regard to a plurality of beam portions which are adjacent to the beam bearings. Next, the correlation level between the signal-intensity profiles at the up-modulating interval and the down-modulating interval is determined, and pairing is performed in sequence starting from the profiles having a higher correlation level.

Abstract: In the on-vehicle radar apparatus of the present invention, the vertical scanning width of the radar beam is narrowed, before the horizontal scanning, thereby avoiding unnecessary data processing and improving the data processing efficiently. Further, the S/N ratio of the target detection signal is increased, thereby stabilizing the distance detection and its accuracy. The vertical scanning antenna is a single travelling wave excitation antenna (TWEA) constructed by a plurality of antenna elements. At the same time, the horizontal scanning antenna is a multi-channel antenna wherein a plurality of TWEAs is assigned to a plurality of horizontal directions. The horizontal scanning angle is arbitrarily widened by increasing the number of TWEAs.

Abstract: A wideband receiver system capable of simultaneously receiving multiple independent RF input signals from different sources which signals can be polarized (linearly or circularly) differently and exhibit different scan angles.

Abstract: An apparatus and method for performing closed-loop beam pointing of a narrow beam at each one of a plurality of target nodes of a communication network, in accordance with a TDMA multiplexing scheme. The invention employs a process similar to coning to obtain a plurality of scan points for each target node. A signal strength of a signal received from each node is recorded and used by the invention to determine an optimal pointing direction relative to each node. This optimal pointing direction is updated repeatedly as each of the target nodes is scanned. The invention provides the accuracy of closed loop beam pointing to be employed with TDMA communication links, which in turn allows using larger PAA's with narrow beams, and thereby permitting higher data transfer rates to be realized over each communication link.

Abstract: A combined defense and navigational system on a naval vessel is disclosed. The disclosed system includes a track-while-scan pulse radar which is controlled to provide either navigational information or tracking information on selected targets. Additionally, the disclosed system includes a plurality of guided missiles, each of which may be vertically launched and directed toward intercept of a selected target either by commands from the track-while-scan radar or from an active guidance system in each such missile.

Abstract: An active array radar system is controlled by photonic signals. The array of N antenna elements is divided into M subarrays, each having N/M antenna elements. Tunable lasers provide M optical wavelengths within non-overlapping bands. For transmission, a microwave transmit pulse is amplitude modulated onto the M optical signals. Time delays are introduced for an offset between elements in a subarray and for an offset between subarrays. By using wavelength division multiplexing each antenna element on the array has a true time delay.

Abstract: Beams are irradiated in three directions by switching an irradiation direction of a mainlobe of an antenna by stages, and an echo is received from a detection object obtained in the mainlobe or a sidelobe in each irradiation direction. Then, reflection power intensity in each irradiation direction is found from the received echo, and pattern of relative variation of the reflection power intensity (power intensity pattern) in each irradiation direction is generated. Meanwhile, a detection region is divided into seven bearings “c” to “i” and a power intensity pattern when an object exists in each bearing is previously stored as a reference pattern in each bearing. Then, the bearing in which the detection object exists is specified by comparing the power intensity pattern obtained from the received echo with the reference pattern in each bearing.

Abstract: A pulse radar system capable of mapping multiple targets essentially simultaneously using a single radar antenna. By alternately transmitting radar pulses toward multiple targets positioned at different angles relative to the antenna and alternately receiving return signals from the multiple targets as the radar antenna is switched between multiple beam positions, a time-interleaved radar operation is achieved which enables multiples targets to be mapped, and thus tracked, at the same time. A different radio frequency is preferably employed for each target so as to avoid interference and ambiguous returns. Using the teachings of the present invention, between two and twenty radar maps, and possibly more, can be generated simultaneously in approximately the same amount of time required to map a single target using conventional systems of the prior art.

Abstract: A radar device set on an automobile includes a transmitter for transmitting forward a beam of electromagnetic waves, a receiver for receiving reflected waves of the transmitted beam from a vehicle traveling in front, a measuring device for measuring a distance to the vehicle in front based on outputs from the receiver and a command outputting device for outputting a specified command signal when the distance measured by the measuring device is decreasing and reaches a threshold distance below which the measuring device becomes incapable of measuring the distance from the outputs from the receiver, and a beam adjusting device for changing either the elevation angle of the beam or its angular range of vision in response to the command signal.

Abstract: A pulse radar system capable of mapping multiple targets essentially simultaneously using a single radar antenna. By alternately transmitting radar pulses toward multiple targets positioned at different angles relative to the antenna and alternately receiving return signals from the multiple targets as the radar antenna is switched between multiple beam positions, a time-interleaved radar operation is achieved which enables multiples targets to be mapped, and thus tracked, at the same time. A different radio frequency is preferably employed for each target so as to avoid interference and ambiguous returns. Using the teachings of the present invention, between two and twenty radar maps, and possibly more, can be generated simultaneously in approximately the same amount of time required to map a single target using conventional systems of the prior art.