Abstract: A method for detecting interference in a received signal received by a radar sensor of a motor vehicle is disclosed. For detecting a target object in an environment of the motor vehicle, a transmit signal is emitted by the radar sensor, which includes a sequence of consecutive frequency-modulated chirp signals. The radar sensor then receives an echo signal reflected on the target object as the received signal with the superimposed interference. After receiving the received signal, the interference in the chirp signals of the received signal is detected.

Abstract: A radio frequency transmission signal is transmitted from a transmission antenna with a predetermined transmission period, and a signal of a reflected wave reflected from a target is received by a reception antenna. A code generator generates a first code sequence and second code sequence that constitute a pair of complementary codes. A first modulator modulates the first code sequence to generate a first transmission signal. A second modulator modulates the second code sequence to generate a second transmission signal. A quadrature modulator performs quadrature modulation by using the generated first and second transmission signals. The radio frequency transmission signal is generated from a signal that is quadrature modulated, and transmitted from the transmission antenna.

Abstract: Systems and techniques relating to IQ mismatch estimation and compensation are described. A described technique includes obtaining samples of a received signal via circuitry having an IQ mismatch; determining an estimated gain imbalance parameter for the IQ mismatch based on an in-phase average value of in-phase training samples and a quadrature average value of quadrature training samples; determining an estimated phase imbalance parameter for the IQ mismatch based on a combined average value, the estimated gain imbalance parameter, and a squared average value, the combined average value being based on a pair-wise multiplication of the in-phase training samples and the quadrature training samples, the squared average value being based on squared versions of the in-phase training samples; updating the in-phase data samples based on the estimated gain imbalance parameter to produce updated in-phase data samples; and updating the quadrature data samples by respectively adding quadrature update values thereto.

Abstract: A transmitter/receiver arrangement comprises a digital arbitrary waveform generator AWG connected to a transmitter. Said waveform generator is configured to generate an arbitrary waveform within a given bandwidth. Said transmitter/receiver arrangement further comprises an antenna arrangement configured to emit a transmitter signal, and to receive an incident signal, a receiver configured to receive a receiver signal, and an analog isolator connected to said antenna arrangement, said transmitter, and said receiver. Said analog isolator is adapted to route said transmitter signal from said transmitter to said antenna arrangement, and said incident signal from said antenna arrangement to said receiver, and to isolate said transmitter signal from said receiver signal. Said receiver is adapted to cancel any residual transmitter signal in said receiver signal by means of at least one digital model of at least said isolator, said antenna arrangement, and said transmitter.

Abstract: Mixer unit for a radar sensor for motor vehicles, having an I mixer and a Q mixer which are connected in parallel branches between an oscillator port and an RF port with the aid of power splitters. A switch is situated between each of the power splitters and the Q mixer which allows the signal arriving from the power splitter to be selectively decoupled from the Q mixer and switched to a high-frequency ground. A transformation element is provided between the high-frequency ground and the particular node point of the power splitter which transforms the high-frequency ground into an open line at the node point.

Abstract: Apparatus, the apparatus having at least one processor and at least one memory having computer-readable code stored thereon which when executed controls the at least one processor to perform a method comprising: obtaining in-phase and quadrature samples of a received radio signal at least first and second discrete instances in time; processing the samples to provide information relating to the amplitude and/or phase of the received radio signal at the first and second instances in time; using the amplitude and/or phase information of the received radio signal at the first and second instances in time to determine whether interference is present on the received radio signal; forwarding the complex signal parameters for processing if interference is determined not to be present; and discarding the complex signal parameters without forwarding them for processing if interference is determined to be present.

Abstract: A homodyne radar system includes an oscillator, an antenna, a low noise amplifier, a mixing subsystem and a directional coupler. The oscillator is configured to generate a transmit signal and a local oscillator signal. The antenna is configured to transmit the transmit signal and to receive a receive signal. The low noise amplifier is configured to amplify the receive signal. The mixing subsystem is configured to receive and mix the transmit signal and the receive signal to produce an output signal. The directional coupler is coupled to the antenna, the oscillator, the low noise amplifier and the mixing subsystem. The directional coupler is connected and configured to provide a low-loss transmission path from the antenna to the low noise amplifier and a high loss transmission path from the oscillator to the antenna.

Abstract: An electronic scanning radar apparatus mounted on a moving object includes a receiving unit including a plurality of antennas receiving a received wave arriving from a target having reflected a transmitted wave, a beat signal generating unit generating a beat signal from the transmitted wave and the received wave, a frequency resolving unit resolving the beat signal in beat frequencies and to calculate complex data based on the beat signal resolved for each beat frequency, and an azimuth detecting unit calculating a direction of arrival of the received wave based on original complex data calculated based on the beat signal, wherein the azimuth detecting unit includes a data extending unit generating extended complex data by extending the number of data based on the original complex data, and a first computation processing unit calculating the direction of arrival of the received wave based on the extended complex data.

Abstract: An I/Q mixer and processing method for a radar system include an RF input and an LO input. Phase shifters apply a selectable phase shift to the LO signal to produce a first phase-shifted version of the LO signal and a second phase-shifted version of the LO signal, the first and second phase-shifted versions of the LO signal being in quadrature. A first set of switches is controllable to selectively apply the selectable phase shift to the LO signal. A first mixer unit receives the RF signal at a first input of the first mixer unit, and a second mixer unit receives the RF signal at a first input of the second mixer unit.

Abstract: A radar sensor for motor vehicles, having a transmitting part, which has two oscillators and a 90° phase shifter for generating a transmission signal, a first comparison signal, and a second comparison signal, which is phase shifted by 90° with respect to the first comparison signal, and a receiving part having an I mixer for mixing a received signal with the first comparison signal and a Q mixer for mixing the received signal with the second comparison signal, in which the transmitting part has a first transmit mixer, whose inputs are directly connected to the two oscillators, and a second transmit mixer, whose one input is directly connected to a first of the two oscillators and whose other input is connected via the phase shifter to the other oscillator.

Abstract: In an environment inspection mode of a calibration system, a radar device executes a signal analysis process to calculate an eigenvalue ratio of each comparison eigenvalue. The eigenvalue ratio has a small value when a pair of eigenvalues corresponding to arrival radar waves has a strong correlation. On the other hand, the eigenvalue ratio has a large value when the eigenvalue ratio is calculated between an eigenvalue and thermal noise. When there is no eigenvalue which is not more than a reference threshold value, the radar device indicates a notice that the current environment is suitable for the calibration of the radar device. On the other hand, when there is presence of at least one eigenvalue of not more than the reference threshold value, the radar device indicates a notice that the current environment is unsuitable for the calibration of the radar device.

Abstract: A method for providing a plurality of narrow pulses is provided. A first pulse having a first width is received by a delay line having a plurality of delay cells. This first pulse has a first width. In response to this first pulse, a plurality of second pulses is generated by the delay line, where each second pulse has a second width that is less than the first width. First and second delay pulses are also generated by the delay line, and a delay for each delay cell in the delay line can then be adjusted if a rising edge of the second delay pulse is misaligned with a falling edge of the first delay pulse.

Abstract: A radar system comprises a transmitting device comprising a reference frequency source, for generating a reference frequency signal; a direct-digital synthesizer, coupled to the reference frequency source, for generating a synthesized frequency signal according to the reference frequency signal; a phase lock loop, coupled to the direct-digital synthesizer, for converting the synthesized frequency signal to an output signal; a transmitting antenna, coupled to the phase lock loop, for emitting the output signal to the air; and a loop switch module, coupled to the phase lock loop, for switching the phase lock loop between an open loop mode and a closed loop mode; and at least one receiving device, for receiving at least one wireless signal, and processing the at least one wireless signal according to the output signal generated by the phase lock loop.

Abstract: This disclosure provides a range side lobe removal device, which includes a pulse compressor for acquiring a reception signal from a radar antenna and generating a pulse-compressed signal by performing a pulse compression of the reception signal, a pseudorange side lobe generator for generating a pseudo signal of range side lobes of the pulse-compressed signal based on the reception signal, and a signal remover for removing a component corresponding to the pseudo signal from the pulse-compressed signal.

Abstract: A method for communicating signals in an ultra high bandwidth system that compensates for carrier frequency offset is provided. A baseband transmit signal having a plurality of data bits is generated. The baseband transmit signal is upconverted to a radio frequency (RF) transmit signal using a first local oscillator signal having a first carrier frequency. An offset cancellation for the offset between the first carrier frequency and a second carrier frequency for a second local oscillator signal that is used to downconvert an RF receive signal is calculated. The offset cancellation is applied to a plurality of phase rotators, and the RF transmit signal is transmitted over a phased array.

Abstract: A communication device includes an oscillator to generate an oscillation signal; a harmonic generator to generate a higher harmonic wave from the oscillation signal; a first filter to take out a first high frequency signal; a second filter to take out a second high frequency signal; a down conversion mixer to use the second high frequency signal to perform down conversion of a signal obtained by receiving a reflected signal of the first high frequency signal; a hybrid coupler to generate a first intermediate frequency signal and a second intermediate frequency signal, which are orthogonal with each other; a first mixer to take out a first baseband signal by mixing an output from the down conversion mixer with the first intermediate frequency signal; and a second mixer to take out a second baseband signal by mixing an output from the down conversion mixer with the first intermediate frequency signal.

Abstract: A method and system for suppressing unwanted signals when detecting objects of interest in a detection system comprising an antenna system and two or more receive beams. A background map is created by range, azimuth and Doppler. Locations within the residual clutter in the moving Doppler bins are selected for nulling. Adaptive nulling is performed independently on each Doppler bin of the selected location to enable Doppler-specific spatial nulling for the same range and azimuth bin.

Abstract: A radio frequency ranging system is grounded in establishing and maintaining phase and frequency coherency of signals received by a slave unit from a master unit and retransmitted to the master unit by the slave unit. For a preferred embodiment of the invention, coherency is established through the use of a delta-sigma phase-lock loop, and maintained through the use, on both master and slave units, of thermally-insulated reference oscillators, which are highly stable over the short periods of time during which communications occur. A phase relationship counter is employed to keep track of the fractional time frames of the phase-lock loop as a function of the reference oscillator, thereby providing absolute phase information for an incoming burst on any channel, thereby enabling the system to almost instantaneously establish or reestablish the phase relationship of the local oscillator so that it synchronized with the reference oscillator.

Abstract: An apparatus according to an embodiment of the present invention for providing a reduced representation in a frequency-domain, based on a time-based RF signal, has a time-frequency converter adapted to transform the time-domain RF signal to obtain a frequency-domain representation based on the time-domain signal and an entropy encoder adapted to obtain the reduced representation based on the frequency-domain representation by entropy encoding.

Abstract: Disclosed is a distance measuring apparatus which includes: a first pulse generating means (135) which generates reference signals; a second pulse generating means (137) which generates subject detection signals; a time measuring section (139) which measures a period of time from a time when a first pulse is generated to a time when a second pulse is generated; a first phase detecting section (141) which detects the first phase of a signal received using a signal at a first frequency; a second phase detecting section (163) which detects the second phase of a signal received using a signal at a second frequency; and a distance calculating section (165) which calculates the distance to the subject on the basis of output from the time measuring section, the first phase detecting section and the second phase detecting section.

Abstract: An electronic scanning radar apparatus in accordance with an embodiment of the present invention, a frequency resolving unit resolves beat signals into beat frequencies having a predetermined frequency bandwidth and calculates complex data based on the resolved beat signals for each beat frequency. An azimuth calculating unit estimates a number of received waves based on eigenvalues of a matrix being part of a primary normal equation having complex data as elements calculated from the beat signals, creates coefficients calculated as a solution of a secondary normal equation of a signal subspace created based on eigenvalues and eigenvectors corresponding to the number of the estimated waves, and calculates a DOA of a received wave based on the created coefficients.

Abstract: A wireless ranging system for determining a range of a remote wireless device may include a wireless transmitter and a wireless receiver. The wireless ranging system may also include a ranging controller to cooperate with the wireless transmitter and receiver to generate a multi-carrier base waveform, transmit a sounder waveform to the remote wireless device including concatenated copies of the multi-carrier base waveform, and receive a return waveform from the remote wireless device in response to the sounder waveform. The ranging controller may also generate time domain samples from the return waveform, convert the time domain samples into frequency domain data, and process the frequency domain data to determine the range of the remote wireless device.

Abstract: In embodiments a system to generate a dual frequency, circularly polarized beam of rotating electromagnetic radiation comprises a first radiation source to generate a first radiation beam at a first frequency, a second radiation source to generate a second radiation beam at a second frequency, different from the first frequency, and a tee. In some embodiments the tee receives the first radiation beam and the second radiation beam, outputs a third radiation beam which represents a sum of the first radiation beam and the second radiation beam, and outputs a fourth radiation beam which represents a difference between the first radiation beam and the second radiation beam, wherein the third radiation beam and the fourth radiation beam are separated by a ninety-degree phase shift. The system further comprises a combiner to combine the third and fourth beams to produce an output beam. Other embodiments may be described.

Abstract: A phased-array receiver comprises a plurality of analog beamforming receive channels, each comprising an antenna element arranged to receive a radio frequency signal and a channel output arranged to provide an analog channel output signal. At least one of the plurality of analog beamforming receive channels comprises an in-phase downconversion mixing circuit connected to the antenna element and a local oscillator source and arranged to provide a downconverted in-phase signal to a phase rotation circuit, and a quadrature downconversion mixing circuit connected to the antenna element and the local oscillator source and arranged to provide a downconverted quadrature signal to the phase rotation circuit. The phase rotation circuit is arranged to provide to the channel output a phase-shifted analog output signal generated from the downconverted in-phase signal and the downconverted quadrature signal.

Abstract: Systems, methods and apparatus related to a high speed, high dynamic range and low power consumption radar system are provided herein. The radar system may include an analog correlator which combines various pulse replication schemes with various parallel integrator architectures to improve the detection speed, dynamic range, and power consumption of conventional radar sensors. The radar system may further include a matched filter for determining a match of a portion of a received PCR signal and producing an output signal in response to further improve the speed of detection of the radar system.

Abstract: In accordance with one of embodiments of the present invention, a frequency resolution processing unit calculates complex number data based on a beat signal caused by a receiving wave coming from a target and a transmission wave. A target detection unit detects a peak value from the intensities of beat frequencies, and then detects an existence of the target. The target link unit makes association between a target detected in the present detecting cycle and the target detected in the past detecting cycle. A direction estimating unit generates a generative complex number data based on the complex number data so as to correspond to a data generation unit. The direction estimating unit calculates, for each antenna, an incoming direction of the receiving wave based on each of normal equations formed by use of the complex number data of the beat frequency which an existence of the target is detected and the generative complex number data.

Abstract: The invention provides a pulse radar apparatus, and a control method thereof, that permits to readily downsize and to lower its cost and allows information on an object to be detected in high precision by removing an influence of noise when a gain of a variable gain amplifier is discontinuously changed corresponding to detected distance, with a simple configuration. A variable gain amplifier 135 configured to adjust a gain corresponding to a distance gate is used to be able to detect weak reflected wave from a distant object and to amplify a reflected wave from a short distance with a low gain. An offset noise from the variable gain amplifier 135 is prepared together with interference noise and self-mixing noise in advance as a replica signal of unwanted wave and the replica signal is removed from a baseband signal in detecting the object T.

Abstract: This disclosure describes a radar system that in certain embodiments can, among other features, take into account the phase noise and/or drift of a transmit signal when generating a nulling signal. A receiver of the radar system can produce an IF signal by mixing a received signal with a local oscillator. The receiver can also mix the local oscillator with a transmit signal provided directly by the transmitter to the receiver to produce a control signal. Using the control signal to generate a nulling signal, the receiver can maintain or substantially maintain phase coherence between the nulling signal and the transmit signal. As a result, in certain embodiments, more precise nulling can occur, resulting in greater receiver sensitivity. Improved receiver sensitivity can provide a greater maximum detectable range and/or improved target detection.

Abstract: An electronic scanning type radar device mounted on a moving body includes: a transmission unit transmitting a transmission wave; a reception unit comprising a plurality of antennas receiving a reflection wave of the transmission wave from a target; a beat signal generation unit generating a beat signal from the transmission wave and the reflection wave; a frequency resolution processing unit frequency computing a complex number data; a target detection unit detecting an existence of the target; a correlation matrix computation unit computing a correlation matrix from each of a complex number data of a detected beat frequency; a target consolidation processing unit linking the target in a present detection cycle and a past detection cycle; a correlation matrix filtering unit generating an averaged correlation matrix by weighted averaging a correlation matrix of a target in the present detection cycle and a correlation matrix of a related target in the past detection cycle; and a direction detection unit compu

Abstract: A method for providing a plurality of narrow pulses is provided. A first pulse having a first width is received by a delay line having a plurality of delay cells. This first pulse has a first width. In response to this first pulse, a plurality of second pulses is generated by the delay line, where each second pulse has a second width that is less than the first width. First and second delay pulses are also generated by the delay line, and a delay for each delay cell in the delay line can then be adjusted if a rising edge of the second delay pulse is misaligned with a falling edge of the first delay pulse.

Abstract: A homodyne radar system includes an oscillator, an antenna, a low noise amplifier, a mixing subsystem and a directional coupler. The oscillator is configured to generate a transmit signal and a local oscillator signal. The antenna is configured to transmit the transmit signal and to receive a receive signal. The low noise amplifier is configured to amplify the receive signal. The mixing subsystem is configured to receive and mix the transmit signal and the receive signal to produce an output signal. The directional coupler is coupled to the antenna, the oscillator, the low noise amplifier and the mixing subsystem. The directional coupler is connected and configured to provide a low-loss transmission path from the antenna to the low noise amplifier and a high loss transmission path from the oscillator to the antenna.

Abstract: According to one embodiment, a weather radar apparatus includes a transmitting/receiving unit configured to transmit a radar wave to an observation target and receive a reflected wave, a distribution unit configured to distribute a received signal of the reflected wave to a main path and at least another path, an extraction unit configured to extract, from a signal of the other path, an interference wave signal extracted from another radio station, and a removing unit configured to remove the interference wave signal extracted from a signal of the main path.

Abstract: To generate a pulse for ranging, a kernel is convolved with a spreading sequence. The spreading sequence is parametrized by one or more ordered (length, sparsity) pairs, such that the first sparsity differs from the bit length of the kernel and/or a subsequent sparsity differs from the product of the immediately preceding length and the immediately preceding sparsity. Alternatively, a kernel is convolved with an ordered plurality of spreading sequences, all but the first of which may be non-binary. The pulse is launched towards a target. The reflection from the target is transformed to a received reflection, compressed by deconvolution of the spreading sequence, and post-processed to provide a range to the target and/or a direction of arrival from the target.

Abstract: Methods and systems for post processing synchronization of bistatic radar data are disclosed. A transmitter is configured to transmit pulses at a first rate controlled by a first local oscillator. A receiver is configured to receive pulses at a second rate controlled by a second oscillator. A processing device is configured to synchronize, with respect to the first rate, in-phase quadrature data received from the receiver using a keystone formatting technique.

Abstract: According to one embodiment, a Doppler radar apparatus includes a quadrature detection unit configured to quadrature-detect a received signal of a reflected pulse from an observation target, and generate time-series data including an in-phase component and a quadrature component, an interference judgment unit configured to judge whether an interference signal is mixed into the received signal based on the time-series data, a correction unit configured to correct a vector expressed by the in-phase component and the quadrature component such that variation with respect to time of a deviation angle of the vector continues when the interference judgment unit has judged that an interference signal is mixed into the received signal, and a calculation unit configured to calculate a Doppler velocity of the observation target based on an amount of variation with respect to time of the deviation angle of corrected vector.

Abstract: A process is provided for analyzing a radar signal using CLEAN to identify an undetected target in sidelobes of a detected target. The process includes obtaining system impulse response data of a waveform for a point target having a signal data vector based on a convolution under conjugate transpose multiplied by a target amplitude vector plus a noise vector, estimating the target amplitude vector, and applying a CLEAN Deconvolver to remove the detected target from the data signal vector based on the estimate amplitude vector absent the detected target and an amplitude vector of an undetected target. The process further includes building a detected target vector with the amplitude estimate vector, setting to zero all elements of the detected target vector except at an initial time, and recomputing the amplitude estimate vector by a Reformulated CLEAN Detector.

Abstract: A System and Method for CW interference suppression in pulsed signal processing having a front-end, an A/D converter, a data store, and a suppressor module coupled to both the A/D converter and the data store. The front-end is operable to receive a waveform and communicate such to the A/D converter to digitize for processing by the suppressor module. The suppressor module being operable to further process the digitized waveform by way of applying a FFT to obtain a corresponding amplitude spectrum of the digitized waveform, clipping the amplitude spectrum to obtain a clipped amplitude spectrum, performing successive piece-wise IFFTs on the positive frequency points of the clipped amplitude spectrum to obtain multiple amplitude-time series, each having a frequency value assigned, and then stacking such amplitude-time series successively in the data store to form a time-frequency spectrogram array to thereby facilitate suppression of interference signals and detection of data pulses.

Abstract: A method and apparatus of determining a wave height directional spectrum of an ocean wave field using the intermediate-frequency (IF) signal from marine radars with a rotating antenna, using either a fully coherent or a standard non-coherent transmitter/receiver modified for coherent-on-receive use. The method may include receiving the IF radar ocean surface echo signal for a series of transmit pulses, at a sequence of azimuthal antenna positions, and a number of antenna rotations covering several minutes, then generating a matrix of complex IF signal samples from these, deriving phases for each sample, generating the difference in phase for consecutive azimuths, then Doppler shifts, and finally radial velocities.

Abstract: A signal processing method includes transforming a received NLFM waveform from a first domain to a second domain, multiplying the transform of the received NLFM waveform with a complex conjugate of a low-pass filtered and transformed reference signal, and inverse transforming a product of the multiplication from the second domain to the first domain.

Abstract: A radar sensor for motor vehicles, having a transmitting part, which has two oscillators and a 90° phase shifter for generating a transmission signal, a first comparison signal, and a second comparison signal, which is phase shifted by 90° with respect to the first comparison signal, and a receiving part having an I mixer for mixing a received signal with the first comparison signal and a Q mixer for mixing the received signal with the second comparison signal, in which the transmitting part has a first transmit mixer, whose inputs are directly connected to the two oscillators, and a second transmit mixer, whose one input is directly connected to a first of the two oscillators and whose other input is connected via the phase shifter to the other oscillator.

Abstract: Modern tactical radars frequently use phase shifters to electronically specify or steer the spatial position of the antenna beam without requiring mechanical motion of the antenna. These phase shifters can only be set correctly for a specific frequency. If a waveform is transmitted through the antenna which consists of multiple segments which differ in frequency or modulation from that frequency used to steer the position of the beam, errors are introduced into the monopulse measurement. These monopulse errors are reduced or eliminated by correction factors. The monopulse errors are corrected by pre-computed factors or terms which result from the differences in frequency and modulation used in the waveform from the frequency used to steer or position the beam. Correction is also provided for radar altitude. These correction factors are easily pre-computed and applied only when needed to minimize the computational requirements.

Abstract: In a method for adaptive calculation of pulse compression filter coefficients for a received signal in a radar installation, which received signal is evaluated with the aid of a complex pulse compression mismatch filter, a pulse compression filter coefficient set h(t) is calculated for an ideal theoretical received signal s(t) for a pulse compression mismatch filter, such that a pulse compression output signal results with a desired main lobe to side lobe ratio.

Abstract: A signal generation system suitable for use in a radar system comprises a local oscillator (LO) and an intermediate frequency (IF) oscillator, wherein the IF oscillator is a Direct Digital Synthesizer (DDS), and the LO is a free running oscillator not itself locked to another oscillator but which acts as a clock reference for the DDS and is the highest frequency oscillator in the system. The LO may also act as a reference for a receive chain digitizer. The invention exploits phase noise advantages of a free running oscillator at some distance from the carrier whilst maintaining coherency with other system components. The system typically finds application in FMCW radars.

Abstract: A judging and controlling part 110 comprises an operation mode judging unit 111, a pulse width selecting unit 112, and a band limiting width selecting unit 113, wherein the operation mode judging unit 111 receives a signal of a gear state from a predetermined controlling device in a vehicle, and then judges the operation mode thereof. Based on a result of the judgment at the operation mode judging unit 111, the pulse width selecting unit 112 and the band limiting width selecting unit 113 control a wide band impulse generating part 120 and a band width limiting part 150, respectively.

Abstract: To suppress cross-ambiguities in the examination of an ice region or dry region by means of aircraft- or aerospace-supported radar echo sounding, the region to be examined is overflown by a radar sensor (6) by multiple compatible radar sensors of the same operating wavelength on multiple spatially separated, substantially parallel paths, wherein the radar signal data received on each path are recorded. The radar signal data recorded for each of the different paths are summed coherently and using a weighting to form a radargram, wherein an adaptive complex-valued weighting for each of the individual paths is performed using a geometrical model which takes into account the topography of the environment of the region to be examined. The weighting for every depth of the examined region is determined by solving a system of linear equations from which is calculated a synthetic antenna pattern which has zeros in the direction of the ambiguities.

Abstract: A radar warning receiver is implemented in low cost integrated circuit form utilizing only one analog component, namely a limiting amplifier. By taking the output of the limiting amplifier and utilizing monobit sampling of the output it has been found that one can provide an integrated circuit single chip radar warning receiver using delay correlation to extract frequency, amplitude and modulation type from signals at or below the noise level.

Abstract: A method to improve a system's signal performance may comprise: generating a first signal, transmitting the first signal, receiving the first signal, and generating a second signal. The method may further comprise: identifying signal distortions generated by at least one of, a transmitter hardware that transmits the first signal and a receiver hardware that receives the first signal, modifying the second signal based upon the identified signal distortions, correlating the first signal and the second signal by a correlator to generate a correlated signal, and outputting the correlated signal.

Abstract: A method includes correlating a plurality of samples of a waveform into a correlation domain to provide a mainlobe defined by a first subset of a plurality of pulse-compressed samples and a plurality of sidelobes defined by a second subset of the plurality of pulse-compressed samples. A weight is calculated for at least one of the pulse-compressed samples, and one of a plurality of SVA filter values is selected to apply to the at least one pulse-compressed sample based on the calculated weight of the at least one pulse-compressed sample. The SVA filter values include one, one minus a quotient of one-half divided by the calculated weight of the at least one sample, and a scale factor having a value greater than zero and less than or equal to one. The selected SVA filter values are applied to the at least one pulse-compressed sample.

Abstract: In a radar system using a radar clutter map comprising a plurality of range-azimuth cells containing parameter data values indicative of time averaged echo returns for affecting alarm threshold levels at range-azimuth locations scanned by the radar system antenna, a method for detecting comprising the steps of obtaining from the radar clutter map a first parameter data value associated with a given cell under test (CUT); determining a second parameter data value using parameter data values of other cells from the plurality of range-azimuth cells from the radar clutter map; comparing the first parameter data value associated with the CUT with the second parameter data value; and generating a signal indicative of a target detection when the first parameter data value exceeds the second parameter data value by a given threshold corresponding to a target false alarm rate.

Abstract: Communication between a remote locator and a transponder is used to determine the relative position of the transponder. The transponder and locator each include a transmitter and a receiver. The locator transmits an inquiry in the form of a relatively powerful cyclically encoded signal with repetitive elements, uniquely associated with a target transponder. Periodically, each transponder correlates its coded ID against a possible inquiry signal, determining frequency, phase and framing in the process. Upon a match, the transponder transmits a synthesized response coherent with the received signal. The locator integrates multiple cyclical response elements, allowing low-power transmissions from the transponder. The locator correlates the integrated response, determines round-trip Doppler shift, time-of-flight, and then computes the distance and angle to the transponder. The transponder can be wearable, bionically implanted, or attached to, or embedded in, some object.