Abstract: In some pseudo-orthogonal waveform embodiments, a radar system transmits pseudo-orthogonal waveforms and performs multiple correlations on a combined single receiver channel signal. In some quadratic polyphase waveform embodiments, a radar system may simultaneously transmit frequency separated versions of a single quadratic polyphase waveform on a plurality of transmit antennas, combine the return signal from each antenna into a combined time-domain signal, and perform a Fourier transformation on the combined time-domain signal to locate a target. The radar system may identify a target, such as sniper's bullet, incoming projectile, rocket-propelled grenade (RPG) or a mortar shell. In some embodiments, the system may estimate the target's trajectory to intercept the target. In some embodiments, the system may estimate the target's trajectory and may further extrapolate the target's trajectory to locate the target's source, such as the sniper.

Abstract: A radar system having a beamless emission signature is described. In one implementation, the radar system includes a transmission system and a receiver system. The transmission system is configured to transmit a pattern comprising a plurality of radar signals having different frequencies simultaneously. The receiver system is configured to receive a reflection of the pattern and combine the plurality of radar signals into a composite waveform forming an image of a target.

Abstract: A system and corresponding method for the concurrent operation of multiple radar systems on a common frequency and in the same geographical area includes a waveform generator that specifies certain operating parameters for the transmitted radar pulses. In a first instance, the carrier frequency can include an offset for each radar system. In a second instance, complementary codes can be used for the radar pulses such that each radar system operates with a unique code for substantially reducing the cross-talk between the radar systems. In another instance, both carrier frequency offset and complementary coded waveforms can be used to increase the number of radar systems that operate concurrently. Carrier frequency offset can also be used to combat range-wrap by using different carrier frequencies for adjacent radar pulses.

Abstract: A radar device includes a code generator, a transmission section, a reception section, a delay section, a despreading process section, a correlation value detection section, a target detection section, an estimation section, an acquisition section, and a correction section. The estimation section estimates a reception intensity of a reflection wave from a target located at a first distance on a basis of a detected correlation value. The acquisition section acquires a cross-correlation value between the first distance and a second distance, on a basis of the estimated reception intensity of the reflection wave from the target located at the first distance, a delayed despreading code used to detect a correlation value for the first distance and a delayed despreading code used to detect a correlation value for the second distance. The correction section corrects the correlation value for the second distance on a basis of the cross-correlation value.

Abstract: The selection of multiple, suitably designed, demodulation reference signals can enable the measurement of a vehicle's speed using continuously transmitted frequency modulated (CTFM) signals. The unique solution of vehicle speed can be used to resolve the range Doppler ambiguity found in conventional CTFM sonar and radar systems. This can enable continuous range and speed estimates of high-speed vehicles with an attendant reduction in transmit power relative to pulse-echo systems with similar measures of performance due to the 100% duty cycle.

Abstract: A system and method is provided for locating objects using RFID tags. The system and method uses an RFID reader and a distance calculator to efficiently and accurately determine the location of objects that include an RFID tag. The RFID reader transmits a plurality of signals to the RFID tag, with the plurality of signals having different fundamental frequencies. In response, the RFID tag backscatter modulates the plurality of transmitted signals to create a plurality of backscatter modulated signals. The RFID reader receives and demodulates the plurality of backscatter modulated signals. The distance calculator determines the phase of the plurality of backscatter modulated signals and determines a rate of change of the phase in the backscatter modulated signals with respect to the rate of change in the fundamental frequency of the transmitted signals and uses this information to calculate the distance to the RFID tag.

Abstract: To provide a method of processing output or base signals (S), in particular intermediate frequency output or base signals, from at least one device, in particular at least one radar device, for determining a distance (d), in particular a small distance on the order of magnitude of approximately zero meters to approximately 7 meters, of an object, by which it is possible to obtain from the raw signals, i.e., the output or base signals, distance information with respect to at least one object located in the detection or sensing range of the device, the following steps are provided: (a) Adaptively determining the background signal (S0) by localized filtering of the output or base signal (S) using at least one localized filter having a specified width (B); (b) Correcting the background of the output or base signal (s) by (b.1) subtracting the determined background signal (S0) from the output or base signal (S) and (b.

Abstract: The invention relates to remote distance measurement by means of a transmitted noise modulated probing signal (E), whereby at least one of a distance (Y(t)) and a velocity (V(t)) in relation to a signal transceiver (200) is determined. The probing of signal (E) is generated on basis of at least one first noise signal (x1(t), x2(t)). The transmitted signal (E) is presumed to be reflected to the signal transceiver (200) via at least one signal reflecting object in the form of an information carrying signal (e). This signal thus constitutes a delayed and possibly doppler shifted version of the transmitted signal (E). Moreover, according to the invention, a second noise signal (x2(t)) is added either to the probing signal (E) before it is transmitted or to the information carrying signal (e) before information pertaining to the reflecting object is derived there from.

Abstract: A continuous wave ranging system, comprising a modulator 2 for modulating an r.f. carrier wave in accordance with a pseudo-random code 3, a transmitting antenna 5 for radiating the modulated signal towards a target, a receiving antenna 6 and receiver 7 for detecting the signal reflected back from the target, a correlator 8 for correlating the reflected signal with a transmitted code with a selected phase shift 9 corresponding to the current range gate to be tested, and means 10, 11, 12 for processing the range/amplitude data from the correlator 8 to discriminate between reflections due to the target and those due to other objects adjacent to the target.

Abstract: A mechanism for combining signals of multiple radars to achieve increased range, radar sensitivity and angle accuracy is provided. A first signal beam is radiated from an antenna of a first radar in the direction of a target. A second signal beam is radiated from an antenna of a second radar in the direction of the same target. The echo signals from the first signal beam and the second signal beam are received at both radars. The echo signals received at the first radar are processed to produce first radar processed echo signals and the echoes signals received at the second radar are processed to produce second radar processed echo signals. The first and second radar processed echo signals are combined to form an aggregate value.

Abstract: A radar device having means for generating a carrier-frequency signal, means for shaping pulses, means for generating modulated radar pulses from the carrier-frequency signal, means for emitting modulated signals as radar pulses, means for receiving radar pulses and means for processing the received radar pulses. The means for receiving the radar pulses have an array including a plurality of antennas, the means for processing the radar pulses have means for dividing the signal power over at least two different reception branches. Means are provided for generating different directional characteristics in the various reception branches.

Abstract: A method for transmitting a radar signal comprises the step of transmitting a series of pulses, each of the pulses being separated in time by an interpulse period, and each of the pulses in the series being modulated in accordance with a different character of a first code

Abstract: A guided wave radar measurement instrument comprises a probe defining a guided wave radar transmission line. A pulse circuit is connected to the probe for generating a very fast stream of pulses on the transmission line and receiving reflected pulses returned on the transmission line. The reflected pulses represent a characteristic of a material being measured. An equivalent time sampling circuit is connected to the pulse circuit operable to sample reflected pulses to build a time multiplied picture of the reflected pulses and comprises a ramp generator circuit generating a saw tooth ramp signal used to selectively delay sampling reflected pulses to build the time multiplied picture. In one aspect of the instrument, the saw tooth ramp signal has a controlled ramp start for each cycle and retrace at an end of the cycle.

Abstract: A radar based sensor detection system comprises a microwave source operative to provide a continuous wave signal at an output. A pulse-former is coupled to the output of the source and is operative to provide at an output a variable length pulse that increases the transmitted energy of the radar system according to the range of object detection. A modulator is coupled to the output of the pulse-former for providing a modulated pulse signal when required. A transmit/receive switch coupled to the output of the modulator is selectively operative between a first transmit position and a second receive position. A transmit channel coupled to the transmit/receive switch transmits the pulse signal when the switch is operated in the transmit position. A receiving channel coupled to the transmit/receive switch receives the modulator signal when the switch is operated in the receive position.

Abstract: A method, used in locating a mobile transmitter, includes providing a set of cross-correlation values, wherein each cross-correlation value is associated with a corresponding TDOA and/or FDOA estimate and is produced by cross-correlating a reference signal with a cooperating signal. The reference signal comprises a copy of a signal transmitted by the mobile transmitter as received at a first antenna and the cooperating signal comprises a copy of the same signal as received at a second antenna. The method further includes determining a most likely range of TDOA and/or FDOA estimates, and then identifying an optimal cross-correlation value within a subset of cross-correlation values corresponding to the most likely range of TDOA and/or FDOA estimates. The TDOA and/or FDOA value corresponding to the optimal cross-correlation value is then employed in calculating the location of the mobile transmitter.

Abstract: A pulse radar device includes a VCO that oscillates a carrier wave that has been modulated in frequency, a switch that modulates the carrier wave generated by the VCO to a pulse wave, a transmission antenna that transmits the pulse wave that has been modulated by the switch as an electromagnetic wave, a reception antenna that receives a reflection wave obtained by reflecting the electromagnetic wave that has been transmitted by the transmission antenna by a target substance, a mixer that demodulates the reception signal that has been received by the reception antenna on the basis of the carrier wave that has been generated by the VCO, and a limiter that limits an amplitude of the demodulation signal which has been demodulated by the mixer.

Abstract: This invention features an improved technique for search and track surveillance. In this invention, distinct and random (in both space and time) signal beams are simultaneous transmitted from an array of transmitter source elements in a manner to cover all sectors about a source location. In addition, countermeasures against a system according to the invention are difficult because the signal waveforms for each beam are distinct and random, making prediction of any signal waveform for any beam very unlikely. An array of receiver sensor elements is provided to receive signals that are scattered from remote objects and may or may not be co-located with and share the elements of the source array element. The scattered signals are received and processed to yield the direction and range of the remote objects.

Abstract: A radar system achieves adjustment of a time-change characteristic of a frequency-modulating voltage signal to a voltage-controlled oscillator for determining a transmitting signal such that the time-change characteristic of the frequency-modulating voltage signal is changed by a minute amount and the frequency spectrum of a beat signal is determined. The adjustment is performed so that the shape of a bulge in signal intensity included in the frequency spectrum is the sharpest.

Abstract: A radar device is described having means (12) for generating a first code, means (18) for modulating a transmission signal in a transmitting branch using the first code, means (32) for delaying the first code, means (20) for modulating a signal in a receiving branch using the delayed first code, and means for mixing a reference signal with a reception signal, multiple receiving channels (111, 112, . . . 11k) being provided, the receiving channels (111, 112, . . . 11k) having means (1201, 1202, . . . 120k) for generating additional codes (C1, C2, . . . Ck), the receiving channels (111, 112, . . . 11k) having means (131, 132, . . . 13k) for demodulating using the respective additional codes (C1, C2, . . . Ck), and means (15) being provided for modulating the transmission signal using at least one of the additional codes (C1, C2, . . . Ck). A method which may be implemented advantageously using the radar device described is also described.

Abstract: A ranging Doppler radar system for identifying, and measuring range, velocity, direction of movement of a vehicle with minimal interference from surrounding environs and with low probability of intercept by the vehicle. The transmitted radar signal is modulated with pseudorandom code which acts as a frequency spreading agent and which allows a radar system to resolve range to targets into discrete “range cells”. Range cells can be grouped to yield a “range segment” which defines a region of roadway, such as a school zone. Traffic can be monitored in all range cells, or only in a predetermined range segment. Maps of traffic flow and vehicle parameters are generated and displayed using radar output parameters. Images representing vehicles violating posted speed limits are identified and highlighted on the traffic flow maps.

Abstract: A spread spectrum radar system, characterized in that the receive radar signal is mixed down to baseband and applied to leak cancellation means for subtracting therefrom an attenuated delayed version of the transmit radar signal to provide a reflected receive radar signal with improved signal-to-noise ratio for further processing and to prevent receiver saturation. The radar allows the capture of the range and speed of identified targets, and facilitates a determination of the target's direction. It exhibits an inherent immunity to electromagnetic interference, and is relatively undetectable by radar detectors. The system is easily reprogrammable for different range resolutions and permits Doppler processing to be independent of the angle between radar signal and the track of the target.

Abstract: A method for transmitting a radar signal comprises the step of transmitting a series of pulses, each of the pulses being separated in time by an interpulse period, and each of the pulses in the series being modulated in accordance with a different character of a first code

Abstract: First-arriving-pulse detector (FAP) circuitry includes a correlator circuitry and a threshold circuitry. The correlator circuitry correlates a received signal with a template signal to provide an output signal. The threshold circuitry provides a first-arriving-pulse signal depending on the relative values of the output signal of the correlator circuitry and a threshold signal.

Abstract: The present invention relates to a system for using signals scattered by targets to determine position and velocity for each of the targets and comprises a set of transmitters and receivers of electromagnetic or acoustic signals, said transmitters and receivers dispersed to known points. Each pair of transmitter and receiver, mono-static or bi-static, is named a measuring facility. The ranges of the transmitters are chosen so that a target at an arbitrary point within the position space can be measured via scattering in the target by at least four, but preferably many more, measuring facilities.

Abstract: In a shift clock signal generating apparatus, a delay line includes a plurality of unit delay elements connected in cascade. A reference clock signal propagates in the delay line while being successively delayed by the unit delay elements. Switches have first ends connected with output terminals of the unit delay elements respectively, and second ends connected with a shift clock signal output path. When specified one among the switches is in its on position, a delayed clock signal which results from delaying the reference clock signal by a prescribed time interval is transmitted via the specified switch to the shift clock signal output path as a shift clock signal. The specified one among the switches is determined on the basis of data representing a phase difference of the shift clock signal from the reference clock signal. The specified switch is set in its on position.

Abstract: Optical distance equipment transmits an optical signal and determines distance by locating the peak of a correlation with the reflected signal. The number of calculations required for the correlation is greatly reduced by using a combination of a coarse and fine correlation. The accuracy of the distance measurement is also improved by calculating the point of intersection of two best fit lines to either side of the correlation peak. The signal is preferably modulated by a maximum length sequence.

Abstract: In an FM-CW radar system, regarding peaks appearing in the frequency spectrum of a beat signal in an FM-CW radar, groups of consecutive peaks in beam bearings within a predetermined frequency difference are regarded as being caused by reflected waves from a single target, and based on a combination of a peak group in an up-modulating interval and a peak group in a down-modulating interval, a relative distance to a target and its relative speed are determined.

Abstract: A radar device is described having means (10) for generating a carrier signal having a carrier frequency fT, means (12, 13, 15, 17) for generating pulses having a pulse repetition rate fPW, means (16) for splitting the carrier signal between a transmission branch and a reception branch, means (18, 19, 21, 27, 29) for delaying the pulses, means (24) for mixing the carrier signal in the reception branch with a reception signal and means (26) for integrating the mixed signal, whereby means (20, 23) for modulating the carrier signal in the transmission branch with the delayed pulses are provided and means for altering the delay in the pulses according to a predetermined code are provided. A method of suppressing interference with the functioning of a radar device is also described.

Abstract: To provide a method of processing output or base signals (S), in particular intermediate frequency output or base signals, from at least one device, in particular at least one radar device, for determining a distance (d), in particular a small distance on the order of magnitude of approximately zero meters to approximately 7 meters, of an object, by which it is possible to obtain from the raw signals, i.e.

Abstract: An apparatus and method of dynamically optimizing an acquisition range of a radar system, including modulating a CW radar signal with a PN code that has an adjustable code frequency of modulation and an adjustable chip length. The method includes transmitting the modulated radar signal and receiving a return radar signal, based on the transmitted radar signal. The method continuously measures a SNR of the received return radar signal, and adaptively tunes the adjustable code frequency of modulation, and adaptively tunes the adjustable chip length, based on the continuously measured SNR. In this manner, the acquisition range of the radar system is optimized.

Abstract: Correlating observations of objects in the sky to determine an orbit includes identifying an initially identified object, determining if the initially identified object will be identifiable again, and identifying a subsequently identified object. A determination is then made by comparing characteristics of the initially identified object with the subsequently identified object. If the object correlate to one another a path or orbit of the object can be determined using the characteristics of the initially identified object and the subsequently identified object.

Abstract: A radar system having an arrangement for producing a code, an arrangement for modulating a transmission signal in a transmit branch, using the code, an arrangement for delaying the code, an arrangement for modulating a signal in a receive branch, using the delayed code, and an arrangement for mixing a reference signal with a receiving signal, the modulation of one of the signals being performed by an amplitude modulation (ASK; “amplitude shift keying”) and the modulation of the other signal by a phase modulation (PSK; “phase shift keying”). Furthermore, a radar system is proposed in which blanking of phase transitions is provided. Also described are methods which may advantageously be carried out, using the radar systems described herein.

Abstract: High dynamic range brightness information is acquired by inputting detection current to a high (adjustable) gain resettable integrator whose output V(t) is compared to a Vth threshold by a comparator whose output is counted by a reset counter as V(t)≧Vth. When a desired count is attained, data acquisition ends, the counter is read, and the entire circuit is reset. A TOF data acquisition circuit includes first and second sequences of series-coupled delay units, and a like number of latch units coupled between respective delay units. A phase discriminator compares output from each chain and feedback a signal to one of the chains and to a comparator and can equalize delay through each chain. A control voltage is coupled to the remaining chain to affect through-propagation delay time. The latch units can capture the precise time when V(t)≧Vth. Successive measurement approximation can enhance TOF resolution.

Abstract: The invention is a method and apparatus for determining the shape and location of objects by trilateration based on the output of a plurality of range sensors. The range measurements from a plurality of sensors are correlated with each other to identify one or more potential objects. With respect to each potential object, it is assumed that the object can be one of a finite number of possible predefined shapes. For each potential object, a metric is calculated for each of the predefined shapes using the set of range measurements upon which the potential object is based defining the likelihood that the set of readings correspond to an actual object of that predefined shape. Each potential object is then assumed to have the predefined shape that yielded the lowest metric (i.e., that yielded the metric that indicates the highest likelihood that the object has the corresponding shape). The list of potential objects is then ordered according by their calculated metrics from lowest to highest.

Abstract: The present invention relates to a radar device and, particularly, to a radar device mounted on a vehicle to be used for a collision alarm and the like. The invention provides a radar device that has a unit for removing the FMAM noise without lowering the signal detection sensitivity. The radar device transmits a frequency modulation signal by switching the frequency modulation signal with a first switching signal, receives a signal reflected from a target object, switches the reception signal with a second switching signal, mixes the switched reception signal with the transmission signal, and further mixes the mixed signals with a third switching signal thereby to obtain a beat signal. The radar device obtains a distance to the target object and a relative speed of the target object from the beat signal.

Abstract: The present invention provides a pulse radar apparatus which is capable of detecting properly an object and measuring a distance up to the object in a short distance even if a leakage signal is contained in a received signal. The pulse radar apparatus includes: transmission means for transmitting an electric wave; reception means for receiving the reflected electric wave into which the electric wave transmitted by the transmission means has been reflected by an object to output the received signal thereof; waveform leading part extracting means for extracting a plurality of leading parts of the received signal outputted by the reception means; sampling means for sampling the output of the waveform leading part extracting means at predetermined time intervals; and detection/distance measuring means for judging on the basis of the time interval data outputted by the time interval measuring means whether or not an object is present and when an object is present, calculating the distance up to the object.

Abstract: A forward electromagnetic wave is generated in accordance with a succession of pseudo random noise code signals. An echo electromagnetic wave caused by reflection of the forward electromagnetic wave at an object is converted into a received signal. Direct-current and low-frequency components are removed from the received signal to generate a filtering-resultant signal. The filtering-resultant signal is compared with a preset decision reference voltage to generate a binary signal. The binary signal is sampled into received data. Calculation is made as to a correlation between the received data and the pseudo random noise code signal. The distance to the object is computed on the basis of the calculated correlation. The pseudo random noise code signal is repetitively generated to produce a succession of the pseudo random noise code signals during a surplus time covering a stabilization time taken by the received signal to stabilize in direct-current voltage level.

Abstract: A filter, includes a first order band pass filter configured to process non-zero amplitude gated radar return samples and process a portion of received zero amplitude return samples. The filter also calculates past filter outputs based on filter outputs generated during previous non-zero gated radar return samples.

Abstract: A method for testing radar system performance is disclosed which utilizes radar data test points in a radar data file. The method includes interpolating GPS data from a flight test to provide a GPS data point for every radar data test point, generating body coordinate values for every point in a corresponding digital elevation map (DEM) file using the interpolated GPS data, and applying a bounding function around at least a portion of the body coordinate values generated from the DEM file at a given time. The method also includes determining which body coordinate value generated from the DEM file is closest a current GPS data point for the given time and comparing the determined body coordinate value to the radar data test points at the given time.

Abstract: A method for resolving radar range ambiguities is disclosed, where the radar is modulated with a phase code which comprises a number of chips. The method includes acquiring a radar return within a verify gate, the verify gate being aligned with one chip of the phase code, determining an amplitude of the return, stepping the gate outbound to a next chip of the code, acquiring a return, and determining if the return has an amplitude greater than a threshold based on the original return. The verify gate is repeatedly stepped outbound to determine if a chip can be found which has an amplitude in excess of the threshold or until returns from all chips within the phase code have been acquired. If such a position is found, search logic of the radar is moved outbound to the chip position which had the highest amplitude return, if not the original chip position and the entire process begins again.

Abstract: A pulse radar device includes a transmitting unit, a receiving unit, a first integrating unit for sampling a reception signal at predetermined time intervals from transmission and integrating results of a predetermined number of times of the sampling at each sampling timing, a differential operating unit for, each time a predetermined time period has passed, reading results of the integrating at each sampling timing and differentiating the read results of the integrating in a sampling direction, a second integrating unit for integrating absolute values of a predetermined number of outputs from the differential operating unit at each sampling timing, a peak detecting unit for detecting the peak of an output from the second integrating unit, a distance measuring and detecting unit for calculating a distance to an object and judging presence or absence of an object based on an output from the peak detecting unit and the like.

Abstract: A radar based sensor detection system comprises a microwave source operative to provide a continuous wave signal at an output. A pulse-former is coupled to the output of the source and is operative to provide at an output a variable length pulse that increases the transmitted energy of the radar system according to the range of object detection. A modulator is coupled to the output of the pulse-former for providing a modulated pulse signal. A transmit receive switch coupled to the output of the modulator is selectively operative between a first transmit position and a second receive position. A transmit channel coupled to the transmit receive switch transmits the pulse signal when the switch is operated in the transmit position. A receiving channel coupled to the transmit receive switch receives the modulator signal when the switch is operated in the receive position.

Abstract: A system and method for imaging objects obscured by a covering layer of snow. The system preferably utilizes a continuous-wave radar generating short-wavelength radio-frequency (RF) signal beam-scanned over angular displacements following a scanning pattern toward a target area. Reflections of the:RF signal from objects buried beneath the snow are registered by an array of RF detectors whose signal magnitudes are summed arid correlated with scan direction to generate a signal providing spatial object information, Which by way of example, is visually displayed. The radio-frequency beam may be scanned over the scene electronically or by either mechanically or electromechanically modulating antenna direction or the orientation of a beam deflector. The system is capable of generating multiple image frames per second, high-resolution imaging, registration of objects to a depth exceeding two meters, and can be implemented at low cost without complex signal processing hardware.

Abstract: A sensor array with a pulse echo radar system with which a carrier signal of a microwave transmitter oscillator is transmitted in the form of pulses with a specified pulse repetition frequency in a transmission window. This radar signal is reflected from a target object and the position of the target object is calculated in a mixer from the times of transmission of the pulse to the arrival of the reflected radiation. An array of several transmitter and receiver units with switches are constructed in which the stochastic pulse sequences of each transmission window in each receiver branch are known and the transmitter and receiver units are linked to one another so that in each of the receiver branches the stochastic pulse sequences of each transmission window are detected separately and thereby the cross echoes may also be analyzed.

Abstract: A continuous signal of a radio frequency source is connected to an antenna using at least one mixer to generate and analyze radar pulses. To generate a radar pulse, the at least one mixer is briefly placed into a state of low throughput loss. After the radar pulse is generated and transmitted, the at least one mixer is switched over to a receive mode to analyze a mixed signal formed by a receive signal, in particular at least one radar pulse reflected by an object, and the continuous signal of the radio frequency source.

Abstract: A proximity measuring apparatus (70) comprises an interrogator (80) for generating an interrogation signal encoded with a reference signature code comprising concatenated codes and emitting it as interrogating radiation. It also incorporates a transponder (90) for receiving the interrogating radiation, demodulating it to extract its signature code and then remodulating it after a delay period to provide a signal for reemission as return radiation therefrom. The interrogator (80) receives return radiation at its antenna (260) and demodulates it to extract its signature code and then correlates the code with the reference code to determine mutual correlation thereof. The interrogator (80) incorporates a computer (290) for controlling a scan direction of the antenna (260) and for measuring time delay between emission of the interrogating radiation therefrom and receipt of corresponding return radiation.

Abstract: This invention features an improved technique for search and track surveillance. In this invention, distinct and random (in both space and time) signal beams are simultaneous transmitted from an array of transmitter source elements in a manner to cover all sectors about a source location. In addition, countermeasures against a system according to the invention are difficult because the signal waveforms for each beam are distinct and random, making prediction of any signal waveform for any beam very unlikely. An array of receiver sensor elements is provided to receive signals that are scattered from remote objects and may or may not be co-located with and share the elements of the source array element. The scattered signals are received and processed to yield the direction and range of the remote objects.

Abstract: The present invention relates to a radar system having means (12) for producing a code, means (18) for modulating a transmission signal in a transmit branch, using the code, means (32) for delaying the code, means (20) for modulating a signal in a receive branch, using the delayed code, and means (26) for mixing a reference signal with a receiving signal, the modulation of one of the signals being performed by an amplitude modulation (ASK; “amplitude shift keying”) and the modulation of the other signal by a phase modulation (PSK; “phase shift keying”). Furthermore, a radar system is proposed in which blanking of phase transitions is provided. The present invention also relates to methods which may advantageously be carried out, using the radar systems according to the present invention.

Abstract: The present invention provides a pulse radar apparatus which is capable of detecting properly an object and measuring a distance up to the object in a short distance even if a leakage signal is contained in a received signal.

Abstract: A ROSAR wire detection method is based upon ROSAR focusing of entire segments of wire. By generating a wire reference signal comprised of a sum of coherent reference signals, the basis for reliable wire detectability is provided.