Abstract: Performance of a radar apparatus including a plurality of transceiver ICs is improved. The radar apparatus includes: a plurality of integrated circuit, which, in operation, perform signal processing on a received signal; and a signal processing circuit, which, in operation, compensates for a deviation between the plurality of integrated circuits based on a difference between leak radio wave components received by receive antennas corresponding respectively to the plurality of integrated circuits.

Abstract: The transmission unit generates a transmission signal obtained by multiplying a linearly FM-modulated pulse signal by a first window function. The pulse compression unit divides a signal, which is obtained by multiplying a first reference signal obtained by multiplying the pulse signal by a second window function different from the first window function, by a complex conjugate part of a second reference signal obtained by multiplying the pulse signal by a third window function, which is a function independent of the second window function, by a complex conjugate part of the transmission signal, and uses this as a reference signal. Then, the pulse compression unit performs pulse compression on the received signal using the reference signal.

Abstract: A passive radar comprises a reception antenna for a signal transmitted by a non-cooperative transmitter, the received signal comprising a static contribution related to propagation of the signal transmitted through a multi-path propagation channel and a dynamic contribution related to propagation of echoes of the transmitted signal from a moving target. The passive radar also comprises a reception chain that includes an analogue-digital converter capable of outputting a digitised signal, a moving target detection unit, a digitised signal processing unit configured to determine an estimation of the static contribution during a calibration phase of the passive radar, a transmission chain that can output an analogue signal representative of the estimation of the static contribution, and a directional coupler configured to output the signal received during the calibration phase of the passive radar to the reception chain.

Abstract: Radar signals are generated to have signal characteristics that define multiple sub-pulses in each of a plurality of pulse repetition intervals (PRIs) of a single radar dwell. Electromagnetic radiation is emitted according to the radar signals and the emitted electromagnetic radiation is sensed as radar return signals over a receive interval in each PRI. Coherent integration is performed on a set of the radar return signals and non-coherent integration is performed on another set of the radar return signals.

Abstract: System and method for determining range to targets using an M-of-N range resolver includes transmitting multiple coherent processing interval (CPI) signals with different pulse repetition frequencies (PRFs) towards the targets, receiving and storing threshold hits from prior N?1 CPIs; converting the threshold hits from the current CPI and prior N?1 CPIs to range unfolded threshold hits; generating a lookup table of the plurality of range unfolded threshold hits from the prior N?1 CPIs; determining the number of the prior N?1 CPIs in which a range unfolded threshold hit from the current CPI has at least one range coincident range unfolded threshold hit from a prior CPI utilizing the lookup table; generating a range resolved threshold hit when the number is greater than or equal to M?1; accumulating range resolved threshold hits; and determining the range to the targets.

Abstract: Disclosed herein are embodiments that relate to phase coded linear frequency modulation for a radar system. Embodiments include transmitting at least two signal pulses. The transmitting includes transmitting a first pulse with a first phase modulation and a first chip rate, and transmitting a second pulse with a second phase modulation and a second chip rate. The second chip rate may be different than the first chip rate. Embodiments also include receiving a signal that includes at least two reflection signals associated with reflection of the at least two transmitted signal pulses. Embodiments further include processing the received signal to determine target information. The processing includes filtering the received signal to time-align the at least two reflection signals. The filtering includes applying a frequency-dependent time delay to one or more of the at least two reflection signals. Additionally, embodiments include removing phase code modulations from the time-aligned reflection signals.

Abstract: A radar transmitter Txs (s=1) generates a baseband transmission signal by modulating a first code sequence having a prescribed code length on the basis of a first transmission timing signal and gives a first transmission phase shift corresponding to each transmission cycle to the transmission signal. A radar receiver Txs (s=2) generates a baseband transmission signal by modulating a second code sequence having the prescribed code length on the basis of a second transmission timing signal and gives, to the transmission signal, a second transmission phase shift that correspond to each transmission cycle and opposite to the first transmission phase.

Abstract: Systems and methods are described for encoding quantized vector parameters in a bitstream are described. An exemplary method may include receiving a vector of integers used in a data compression codebook, the sum of the integers equaling a pulse sum. An initial expected magnitude may be determined for a first integer, the initial expected magnitude being based on the pulse sum, a distribution parameter, and a value corresponding to a number of integers in the vector. The actual magnitude of the first integer may be encoded based on the initial expected magnitude of the first integer. The pulse sum may be adjusted using the encoded actual magnitude. Also, the value corresponding to the number of integers in the vector may be reduced by one. Expected magnitudes for each of the remaining integers of the vector may then be calculated recursively.

Abstract: A radar device is provided, which includes a first sector radar and a second sector radar, each including a code generator that generates two code sequences, a multiplier that multiplies the two code sequences by a coefficient sequence, wherein the two coefficient sequences of the first and second sector radars, respectively, are orthogonal to each other, a transmission signal generator that modulates the orthogonalized two code sequences, and an RF transmitter that transmits the modulated signal including the two orthogonalized two code sequences. At least one of the two orthogonal coefficient sequences for the first and second sector radars, respectively, includes one or more negative coefficients. The two orthogonal coefficient sequences include coefficients, which are identical to each other, in a first transmission cycle, and include coefficients, which are different from each other, in a second transmission cycle different from the first transmission cycle.

Abstract: A method of detecting a vehicle speed is disclosed in the present invention. The method includes outputting a detecting wave, receiving a reflecting wave from an external object when the external object passes through a covering range of the detecting wave, calculating a variation between the detecting wave and the reflecting wave, and reading a table for executing an application program according to information of the table.

Abstract: A demultiplexing device that includes frequency-conversion and reception low-pass-filter units that perform a frequency converting process and a low-pass filtering process for causing a signal to pass through a desired band, perform downsampling to reduce a sampling rate to half of a data rate of an input signal, and output the signal, reception channel-filter units that waveform-shape a signal with a desired frequency characteristic and output the waveform-shaped signal. The demultiplexing device also includes a filter-bank control unit that generates a clock control signal for supplying a clock to frequency-conversion and reception low-pass-filter units and reception channel-filter units corresponding to signal passage bands, based on channel information, and a reception-clock supply unit that supplies a clock to frequency-conversion and reception low-pass-filter units and reception channel-filter units corresponding to signal passage bands, based on the clock control signal.

Abstract: A radar being carried by an aircraft includes means for transmitting an RF wave towards a target, said wave having a double form, a first waveform being composed of at least two sinusoids of different frequencies transmitted simultaneously, the radar comprising reception circuits receiving the signals reflected by the target and analysis means performing the detection of the target on the basis of the signals received. The second waveform is of the pulse type. The transmitted waveform is dependent on the relative speed of the target with respect to the carrier and on the absolute speed of the carrier.

Abstract: A radar system achieves unambiguous target range at a given PRI, in conjunction with unambiguous Doppler, by transmitting CW-LFM pulses and then separating the return signal into subpulses, without requiring any modifications to the transmit waveform. The CW-LFM pulses may be contiguous. The return signals are bandpass-filtered to generate the subpulses, and downconverted to a common frequency such as baseband. Each downconverted subpulse is matched-filtered to the FM slope, and the resulting matched-filtered subpulses are time-aligned. The time-aligned subpulses are Doppler-filtered to determine target velocity.

Abstract: This disclosure provides a radar device including a transmission module for sequentially transmitting two or more kinds of pulse signals having different pulse widths by a predetermined transmitting pattern, a memory module for storing a predetermined number of pulse reply data corresponding to each kind of the pulse signals, the predetermined number being number of transmissions of the kind of the pulse signals, a pulse integrating module for performing pulse integration of the pulse reply data stored in the memory module for each kind of the pulse signal, and an image generating module for generating a radar image using the results of the pulse integration.

Abstract: A signal processing apparatus for a radar transceiver, which receives a reflected signal generated by a target object in response to a frequency modulated transmission signal, and generates a beat signal having a frequency difference between the transmission signal and a reception signal, includes: an azimuth angle detection unit that detects an azimuth angle of the target object on the basis of a peak signal in a frequency spectrum of the beat signal; a peak signal extraction unit that prioritizes extraction of a peak signal corresponding to a predetermined azimuth angle range and a predetermined relative distance range of the target object; and a target object detection unit that detects the target object from the extracted peak signal.

Abstract: A receiving circuit which receives information using a multi-carrier signal comprises a phase rotation amount calculator which calculates a first and a second phase rotation amount of a multi-carrier signal included in a first and a second frequency band according to a pilot-sub carrier included in the first and the second frequency band, a phase storage which stores the first and second phase rotation amount and a phase rotation amount determination unit which calculates a correction amount based on the first phase rotation amount stored in the phase storage and an input multi-carrier signal when the input multi carrier signal is included in the first frequency band, and calculates a correction amount based on the second phase rotation amount stored in the phase storage and an input multi-carrier signal when the input multi-carrier signal is included in the second frequency band.

Abstract: Method and apparatus for improving the detection and discrimination of slow moving or stationary range-Doppler spread objects on or in close proximity to the ground (or sea surface). Invention detects, discriminates and separates radar returns from interference including ground clutter discretes via a coherent process for separating target returns from the myriad of received signals. Thus the method and apparatus improves the probability of detecting and declaring the presence or absence of an object at the same time that the probability of false declaration decreases. The method and apparatus may be applied to the processing of any over resolved object, including airborne radar.

Abstract: A receiving circuit which receives information using a multi-carrier signal comprises a phase rotation amount calculator which calculates a phase rotation amount of a multi-carrier signal included in a first frequency band according to a pilot-sub carrier included in the first frequency band, a converter which calculates a phase rotation amount of a multi-carrier signal included in a second frequency band according to the phase rotation amount of the multi carrier signal included in the first frequency band.

Abstract: A scanning radar system suitable for detecting and monitoring ground-based targets includes a frequency generator, a frequency scanning antenna, and a receiver arranged to process signals received from a target so as to identify a Doppler frequency associated with the target. The frequency generator generates sets of signals, each set having a different characteristic frequency, and includes a digital synthesiser arranged to modulate a continuous wave signal of a given characteristic frequency by a sequence of modulation patterns to generate one set of signals. The frequency scanning antenna cooperates with the frequency generator to transceive radiation over a region having an angular extent dependent on the generated frequencies.

Abstract: A traffic radar utilizes digital signal processing (DSP) to determine targets based on signal strength histories. From these histories, a target vehicle having the strongest Doppler return signal is identified and its speed is displayed, and a target vehicle having the highest frequency return signal is identified and its speed is displayed. The traffic radar may also display the relative strength of the strongest return signal and the relative strength of the highest frequency return signal, thereby showing a comparison of the strengths of the return signals from the target vehicles.

Abstract: A data processor applies transform processing to a first group of samples at a primary sampling rate, where the first group of samples is within a data window associated with at least one of the data blocks. A detector detects an estimated frequency shift between the transmitted signal and the reflected signal based on a primary peak frequency determined by the transform processing at the primary sampling rate. The data processor applies transform processing to a second group of samples at a secondary sampling rate, where the data window contains previously read samples and at least one new sample, if the estimated frequency shift falls within a target response frequency band. The detector detects an observed frequency shift between the transmitted signal and the reflected signal based on a secondary peak frequency determined by the transform processing at the secondary sampling rate.

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: Disclosed is a DBF radar apparatus comprising: an antenna for radiating a transmit signal; a plurality of antennas for receiving the transmit signal reflected from an object; a first selector switch section for sequentially selecting output terminals of the plurality of antennas one at a time for connection to an input terminal by performing switching with a first period; a first downconverting section for downconverting, by using a portion of the transmit signal, a received signal input from each antenna; a low-frequency cut-off filter connected to an output of the first downconverting section; a second selector switch section for connecting an output of the low-frequency cut-off filter to a sequentially selected one of a plurality of A/D converters; and a digital signal processing section for receiving outputs of the plurality of A/D converters, and for applying prescribed processing to the outputs to detect the distance to the object or the relative velocity with respect to the object, wherein, when each a

Abstract: A radar system comprises: a plurality of reception antennas; a transmission wave generating device; a transmission antenna; a mixer; an A/D converter; a storage device which stores the digitized beat signals in association with each of the reception antennas; a Fourier transformation device which Fourier transforms the stored beat signals; a digital beam forming device which generates beam signals at predetermined pitch angles based on the Fourier transformed signals; an orientation detecting device which detects an orientation of the object using the generated beam signals; a distance detecting device which detects a distance to the object using the generated beam signals; and a signal separation processing device which performs separation processing of the beat signals based on the detected orientation and distance of the object, using the beat signals associated with each of the reception antennas, which are Fourier transformed by the Fourier transformation device.

Abstract: A radar system in which a beat signal is generated by transmitting a transmission signal that is subjected to frequency modulation into a triangular wave and receiving a reflection signal from a target, the beat signal is sampled, and a window function is applied to yield a discrete frequency spectrum. When the window function is applied, a first window function having an amplitude that is gently attenuated from the center of the sampling period toward both sides thereof is applied in a lower frequency band in the frequency spectrum (at close range), and a second window function having an amplitude that is sharply attenuated from the center of the sampling period toward both sides thereof is applied in a higher frequency band in the frequency spectrum (at far range).

Abstract: In a periphery monitoring system for monitoring movements of a mobile object around an installation location of a Doppler sensor, a signal output from the Doppler sensor is subjected to an FFT analysis, and a total sum of the frequency levels of all of the frequency bands obtained through the FFT analysis is calculated at predetermined time intervals. A reference level and abnormal level are set based on the calculated total sum. If the calculated total sum exceeds the abnormal level and falls to or below the abnormal level before a first set period passes since the exceeding of the abnormal level, the periphery status is determined to be abnormal. If the total sum exceeds the abnormal level but does not fall to or below the abnormal level even after the first set period passes since the exceeding of the abnormal level, the periphery status is determined to be normal, and the reference level is updated to a new reference level set based on total sums calculated during the first set period.

Abstract: In an FM-CW radar system, a frequency modulating said modulating wave output from said modulating signal generator has a frequency variation skew with respect to a time axis (modulation skew), and the radar system includes a means for varying the modulation skew by controlling the modulation frequency amplitude or modulation period of the modulating signal. The radar system further includes a means for discriminating a signal component varying in response to the variation of the modulation skew, thereby discriminating a signal related to a target object from other signals. In the case of an FM-CW radar system that performs transmission and/or reception by time division ON-OFF control the radar system includes a means for discriminating a signal which, when the frequency used to perform the ON OFF control is varied, varies in response to the variation of the frequency, thereby discriminating a signal related to a target object from other signals.

Abstract: Disclosed is a real-time pulse sorting apparatus of a preprocessor in a pulsed radiation detection system. The apparatus, responsive to digital signals generated by a system receiver, uses the instantaneous frequency as the address input to store discrete data groups in main memory. Each data group, comprising the digital data corresponding to a single analog-to-digital converter sample point, includes the RF signal amplitude, inter-channel phase difference, instantaneous frequency as well as a unique pulse number generated by the pulse sorting apparatus. The present invention further includes a TOA memory for storing the time-of-arrival of each pulse at an address given by the pulse number. The main memory, organized in the form of a frequency-based histogram, together with the TOA memory, linked to the main memory by means of the pulse number pointer, sorts and records RF signal data with minimal processor control and intervention.

Abstract: In a radio wave radar system using a two-frequency CW modulation method, it is possible to detect a distance between a host vehicle and a forward vehicle and to realize a stable ACC following travel, even in a condition in which the relative speed is 0. By combining the two-frequency CW modulation method with the frequency pulse CW modulation method, that is, by using combination with the two-frequency CW method when the relative speed occurs and the frequency pulse CW method when the relative speed is close to 0, even if the relative speed is 0, the IF signal obtained from the reflected wave from the forward vehicle can be generated to detect the existence of the ACC target vehicle, so that it is possible to realize a stable ACC following travel.

Abstract: A radar tracking system for an anti-aircraft, missile, including angle tracking, doppler tracking and range tracking feedback loops operating on sum and difference channels. Fast fourier transform digital filters are used to provide a frequency spectrum of the sum and difference I.F. channels and detection and confirmation algorithms are employed for selecting the F.F.T. target ‘bin’. Adjacent F.F.T. bins are used to simulate a bin centered on the target frequency, shifts of the latter with target/missile acceleration causing frequency errors which are detected by a discriminator and used to control the target I.F. Confirmation of target acquisition is achieved by successive summations of the target bin power the totals being accumulated and compared with upper and lower thresholds. Confirmation and rejection results from total levels outside the thresholds while further accumulation and comparison follow the intermediate condition.

Abstract: In an automotive radio wave radar, a center frequency of a transmitted wave is shifted at a certain cycle, and position information of an obstacle detected at three or more center frequencies is subjected to decision by majority to determine whether detection results of the obstacle are erroneous with the occurrence of jamming. If any of the detection results is determined to be abnormal, the abnormal result is discarded. An automotive radio wave radar is realized which can correctly perform the obstacle detection even in the event of jamming without causing erroneous obstacle detection or omission of the detection.

Abstract: A wave-form generator drives a number of microwave generating devices each operating at different frequency bands. The output of each microwave generator is connected to its own transmission channel of limited bandwidth which contains all the non-linear components necessary for transmission such as an amplifier, T/R switch, rotary joint and beam switch. These individual channels are finally combined onto a common wideband channel which contains only substantially linear components such as a single waveguide and the antenna itself. Because of the isolation between channels there is little or no opportunity for the generation of harmonics or intermodulation distortions which would otherwise occur in a transmitter capable of operating over a very wide bandwidth.

Abstract: A radar is provided which transmits a radar wave whose frequency is so modulated as to rise, fall, and be kept constant cyclically. The radar uses beat signals produced by the radar wave and radar echoes received by two antennas to produce radar data on a target. When it is impossible to pair frequency peaks of the beat signals in a modulated frequency-rising and -falling ranges, the radar determines that the frequency peaks have arisen from different objects so that they overlap each other and uses frequency peaks of the beat signals in a constant modulated frequency range to acquire the radar data.

Abstract: A method for processing pulsed-Doppler radar signals to detect a target includes transmitting radar signals from a radar system according to a predetermined frequency technique including signals having frequency diversity, receiving signals within a frequency band, including a target return signal having a frequency indicative of the velocity of the target, and transforming the target return signal using a Fourier Transform having a variable frequency scale.

Abstract: An in-vehicle pulse radar device includes: an oscillator that generates an electromagnetic wave; a transmission amplifier that transmits the electromagnetic wave generated by the oscillator toward a target substance; an antenna that receives the reception electromagnetic wave reflected by the target substance to output data; reception amplifiers; a reception antenna; an A/D converter; and a signal processing device that pre-sums data which is sampled on the basis of the data from the A/D converter for each of distance gates, subjects the pre-summed data which is a result of the pre-summing process to an FFT process, and obtains a distance between a subject vehicle and the target substance and a relative speed therebetween in accordance with the spectrum frequency and the amplitude information which are a result of the FFT process.

Abstract: From a transmitter (18) and a transmission antenna (10), a first frequency signal having a fixed frequency is transmitted for a predetermined time or more, a second frequency signal having a certain frequency difference from the first frequency signal is transmitted for a predetermined time or more, and a third frequency signal having a frequency difference twice the frequency distance from the first frequency signal is transmitted for a predetermined time or more. Reflected waves from objects under measurement at the respective transmission frequencies are supplied to a reception antenna (11), a mixer (12), an analog circuit unit (13), an A/D converter (14), an FFT (15) and a signal processing unit (16).

Abstract: To measure the absolute speed of a body 100 moving relative to the ground 33 using an onboard speed sensor 1, a radar wave is transmitted towards the ground by an antenna with a wide aperture angle. The wave reflected by a reflecting obstacle on the ground and the transmitted wave are mixed and the frequency content of the low frequency signal obtained is determined. The speed of the moving object and the height of the transmitter and receiver antennas above the ground can then be measured by adjusting a theoretical curve to the time-varying evolution of the Doppler frequency corresponding to the reflecting obstacle.

Abstract: An FM-CW radar processing system pairs up peaks obtained by fast-Fourier transforming a beat signal occurring on an up portion and a down portion of a triangular-shaped FM-CW wave, calculates a distance or relative velocity with respect to a target object based on the peak signal in the up portion and the peak signal in the down portion obtained by the pairing, and compares the distance or relative velocity, obtained after changing the modulating signal for the FM-CW wave, with the distance or relative velocity obtained before changing the modulating signal. If the distance or relative velocity differs before and after changing the modulating signal, the pairing is judged to be mispairing.

Abstract: An inventive frequency modulated continuous wave (FMCW) radar system realizes both of a quick detection of higher relative speed provisional target and a sure detection of smaller relative speed provisional target. The number of detection cycles used for a paring validity check (a test to see if a detected target or a pair of frequencies is an actual target or a pair for an actual target) is set in response to the relative velocity.

Abstract: A scan type radar device capable of detecting a lateral position of a target even if a peak showing the lateral position of the target irregularly fluctuates in the lateral direction as well as reducing the mis-pairing. The former is achievable by changing a reference value of the lateral fluctuation of the target when all the past and present target data fluctuate to an extent exceeding the reference value. The latter is achievable by forecasting a representative peak position at this time in both of up-beat and down-beat from the peak position data at the preceding time and carrying out the past-correspondence grouping of the up-beat and the down-beat at this time in the vicinity of the position of the representative peak forecast this time; the pairing being carried out by using the representative peak calculated by the past-correspondence grouping.

Abstract: A bistatic radar system (100), method and computer program (178) are provided for mapping of oceanic surface conditions. Generally, the system (100) includes at least one transmitter (102) and at least one receiver (106) located separate from one another, and each having a local oscillator locked to a Global Positioning System (GPS) signal received by a GPS synchronization circuit (134) to provide the necessary coherency between the transmitted and received signals. Preferably, the present invention enables an existing backscatter radar systems to be quickly and inexpensively upgraded to a bistatic radar system (100) through the addition of a transmitter (102) and/or receiver (106) separate from the backscatter radar system, the GPS circuit (134), and use of the computer program (178) and method of the present invention.

Abstract: To measure the absolute speed of a body 100 moving relative to the ground 33 using an onboard speed sensor 1, a radar wave is transmitted towards the ground by an antenna with a wide aperture angle. The wave reflected by a reflecting obstacle on the ground and the transmitted wave are mixed and the frequency content of the low frequency signal obtained is determined. The speed of the moving object and the height of the transmitter and receiver antennas above the ground can then be measured by adjusting a theoretical curve to the time-varying evolution of the Doppler frequency corresponding to the reflecting obstacle.

Abstract: A transceiver assembly is provided for use in a Doppler-based traffic radar system for determining the speed of at least one target. The transceiver assembly includes a cover for receiving therein at least some of the component parts of the transceiver assembly. In other words, the cover is positioned over the component parts of the transceiver assembly which are enclosed by a cap removably attached to the cover. A conical antenna horn and turnstile waveguide cavities are formed from a unitary material. The circuitry associated with the transceiver assembly is modularized such that the circuitry may be removed from the transceiver assembly, or more specifically separated from the microwave components of the transceiver assembly, for testing.

Abstract: A transmitted signal and a received signal are combined and the combination is expected to determine whether or not a target signal is present. Either the transmitted signal or the received signal is combined with an auxiliary signal containing a range of frequencies corresponding to an anticipated Doppler shift, so that an output of the combined transmitted and received signal will be present only if a target signal exhibiting a Doppler shift within the anticipated range is present. The auxiliary signal preferably comprises finite-duration signal portions of different types so as to provide a substantially uniform frequency response throughout the selected range.

Abstract: A Doppler-based radar system and related method are provided for determining the direction and speed of at least one selected target traveling in the same lane as a moving patrol vehicle supporting the radar system independent of the direction of the target relative to the platform. The radar system includes an oscillator to generate a signal, an antenna to transmit the signal toward the at least one target and to receive a return signal reflected from the at least one target, a turnstile in communication with the antenna for receiving the return signal and forming processing signals which are different in phase, and circuitry for determining the direction of the at least one target relative to the platform and the speed of the at least one target dependent upon a mode of operation of the radar system.

Abstract: The invention concerns a method and a device to measure the speed (v) of a vehicle relative to a road surface. To increase the accuracy of the speed measurement and in order to be able to determine the speed (v) of the vehicle independently of the diameter and the adhesion of a vehicle wheel on the road surface, the invention proposes that the speed (v) of the vehicle is measured directly on the road surface by utilizing the Doppler effect.

Abstract: A Doppler-based radar system and related method are provided for determining the direction and speed of at least one selected target traveling in the same lane as a moving patrol vehicle supporting the radar system independent of the direction of the target relative to the platform. The radar system includes an oscillator to generate a signal, an antenna to transmit the signal toward the at least one target and to receive a return signal reflected from the at least one target, a turnstile in communication with the antenna for receiving the return signal and forming processing signals which are different in phase, and circuitry for determining the direction of the at least one target relative to the platform. In particular, samples of the processing signals are transformed into the frequency domain and cross-correlated forming cross-correlation components.

Abstract: Disclosed is a radar system capable of obviating a problem that a sufficient improvement of an S/N ratio could not be obtained in the prior art, and comprising a transmitter/receiver for detecting a phase of a receiving signal reflected from an observation target, an A/D converter for converting the receiving signal into a digital signal, a range gate for extracting the receiving signal having a time corresponding to the predetermined pulse width, a data dividing unit for dividing the receiving signals in to two groups of data, an FFT unit for fast-Fourier-transforming one group of data of the two groups of data, an FFT unit for fast-Fourier-transforming the other group of data, a complex conjugating unit for taking a complex conjugate of an output of the FFT unit, a complex multiplying unit for performing a complex multiplication for the every same Doppler frequency component with respect to an output of the former FFT unit and an output of the complex conjugating unit, and a complex adder for executing a co

Abstract: Method and device for calculating a velocity of a moving transmitter using Rayleigh-fading of a received radio signal are presented. The method includes the step of making at least two parallel calculations of at least two respective values using the received radio signal. The at least two respective values resulting from the calculations are then used as the basis for making a decision. The decision results in an optimal value for calculating the velocity of the moving transmitter being chosen from among the at least two respective values. Each of the at least two parallel calculations is carried out by respective devices each having at least one filter and at least one level crossing counter.

Abstract: A system is provided for generating multiple frequencies in a specified frequency band, with a specified step size between frequencies, in which the spectral purity of the frequencies is assured. The switching speed between frequencies is very fast, limited only by the speed of the switches used. In one embodiment, only five tones are generated as the base for the rest of the synthesis, in which the relationship of the five tones is f0+/??f0 and +/? 1/16f0. The subject system may be utilized in air defense systems for generating the transmit channels to be able to permit a missile seeker to transmit a signal at the appropriate frequency. In one embodiment, spectral purity is achieved by providing a number of stages of up converting, expanding, and dividing down of an input signal.