Abstract: Systems, apparatus, and methods are described that provide for detection of a metamaterial surface (metasurface) on a device or object. Multitone EM radiation is transmitted to the object having the metasurface. Two or more heterodyned tones are backscattered from the object and detected.

Abstract: Systems, apparatus, and methods are described that provide for detection of a metamaterial surface (metasurface) on a device or object. Multitone EM radiation is transmitted to the object having the metasurface. Two or more heterodyned tones are backscattered from the object and detected.

Abstract: The present technique provides an apparatus comprising receiver circuitry to receive a signal formed from a plurality of multipath signal components, including a first set of multipath signal components that have been subjected to modulation by interaction with at least one moving part of a target machine. The first set of multipath signal components have time varying signal paths due to the interaction with said at least one moving part. Evaluation circuitry is used to generate, for at least one property of the received signal, an evaluation signal, and modification circuitry then produces a modified evaluation signal by applying a removal operation to at least partially remove from said evaluation signal a contribution to that evaluation signal from the multipath signal components whose associated signal paths are non-time-varying.

Abstract: A method and apparatus are provided for detecting a RADAR signal. RADAR channel data in a frequency range is received, where the frequency range is divided into a plurality of equally wide channels. The received RADAR channel data is digitally processed and analyzed to identify a signal in the RADAR channel data in the frequency range. The frequency range is advanced to a next channel of the plurality of channels, where the frequency range of the next channel of the plurality of channels is non-sequential with the frequency range of the first channel. The steps of receiving, processing, and analyzing are repeated for the next channel of the plurality of channels.

Abstract: An apparatus for detecting a motion of an object in a target space, wherein the object is located at a distance from an image-capturing device which is configured to measure the distance and to provide a sensor signal indicative of the distance, the sensor signal being decomposable in a decomposition including odd harmonics if the object is at rest. The apparatus includes a determining module configured to receive the sensor signal and to generate at least one motion signal which depends on at least one even harmonic of the decomposition of the sensor signal; and a detection module configured to detect the motion of the object based on the at least one motion signal and to provide a detection signal indicating the motion of the object.

Abstract: A method and apparatus are provided for detecting a RADAR signal. RADAR channel data in a frequency range is received, where the frequency range is divided into a plurality of equally wide channels. The received RADAR channel data is digitally processed and analyzed to identify a signal in the RADAR channel data in the frequency range. The frequency range is advanced to a next channel of the plurality of channels, where the frequency range of the next channel of the plurality of channels is nonsequential with the frequency range of the first channel. The steps of receiving, processing, and analyzing are repeated for the next channel of the plurality of channels.

Abstract: Provided is a broadband frequency detector, more particularly, to a frequency detector detecting all the signals for guiding the safe vehicle operation, and radar signals for determining vehicle speeds. The broadband frequency detector comprises: a horn antenna configured to receive signals having specific frequencies; a first amplifier configured to receive the signals having specific frequencies from the horn antenna; a mixer unit configured to receive signals from the first amplifier, wherein the signals are low noise amplified therein; and a second amplifier, arranged in parallel with the amplifier, for transferring signals to the mixer unit after low noise amplifying the signal received from the horn antenna, wherein the second amplifier includes a transistor and a first microwave circuit unit for matching the impedance of the horn antenna and the impedance of the transistor.

Abstract: A method for mitigating helicopter rotor blockage of communications comprising fast fourier transforming (FFT) pilot symbols, implementing a time delay of one frame, applying a forgetting factor to an accumulated spectrum, and performing a leaky coherent integration, wherein the leaky coherent integration adds a result of the fast fourier transform of the one current frame of data to the accumulated spectrum. The method also comprises calculating a threshold, wherein the threshold is based on a mean energy of all FFT bins in the accumulated spectrum, masking the FFT bins, wherein masking comprises retaining only FFT bins that exceed the threshold and above a minimum expected rotor blocking frequency, inverse fast fourier transforming the accumulated spectrum, erasing the pilot symbols below the threshold and removing them from the signal, and erasing data symbols that lie in a blockage by setting associated bit-log likelihood ratios to zero.

Abstract: A method of synthetic imaging comprising the steps of: emitting a first electromagnetic signal having a first frequency from a first radiation source, emitting at least one second electromagnetic signal having a second frequency from a second radiation source, wherein the first and second frequencies are different from each other, substantially simultaneously receiving the first signal and the second signal with a first receiver, substantially simultaneously receiving the first signal and the second signal with at least one second receiver, arranging an object on the path of at least one electromagnetic signal between the radiation sources and the receivers, wherein the signals are reflected by the object before they meet the receivers, and computing an image of the object from the signals received by the receivers and a device for practicing the method.

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: The present invention is a signal processing method to significantly improve the detection and identification of source emissions. More particularly, the present invention offers a processing method to reduce the false alarm rate of systems which remotely detect and identify the presence of electronic devices through an analysis of a received spectrum the devices' unintended emissions. The invention identifies candidate emission elements and determines their validity based on a frequency and phase association with other emissions present in the received spectrum. The invention compares the measured phase and frequency data of the emissions with a software solution of the theoretically or empirically derived closed-form expression which governs the phase and frequency distribution of the emissions within the source. Verification of this relationship serves to dramatically increase the confidence of the detection.

Abstract: An object ranging system operates by transmitting pulses derived from a frequency-swept signal and determining the beat frequency of a combination of the frequency-swept signal and its reflection from an object. A second (or higher) order harmonic is derived from the combination signal. Accordingly, determination of the beat frequency, and hence object range, is significantly enhanced. The frequency sweep is such that frequency changes occur at a substantially higher rate at the beginning of each the pulse repetition interval than at the end. Accordingly, because the frequency changes are concentrated in the period of pulse transmission, even reflections 'from a close object, where the time delay between the source signal and the reflection is very short, will cause a high beat frequency.

Abstract: A method examining an object using millimeter-wave signals includes: (a) providing at least two millimeter-wave signal sources; (b) transmitting at least two millimeter-wave signals having at least two different frequencies from the signal sources illuminate the object; (c) in no particular order: (1) determining whether a return reflected signal is above a threshold level; [a] if yes, processing the return signal to identify object shape; [b] if not, processing another return signal; and (2) determining whether a return intermodulation product or harmonic signal is detected; [a] if yes, processing the return signal to identify object nature; [b] if not, processing another return signal; (d) determining whether checked all return signals; (1) if not, processing another return signal; (2) if yes, proceeding to step (e); (e) determining whether results are satisfactory; (1) if not, changing frequency of at least one of the wave signals; (2) if yes, terminating the method.

Abstract: A system and method for detecting the presence of an RF device and determining a location of the RF device. The system includes a first antenna capable of transmitting a first radar signal and receiving RF signals, a second antenna capable of transmitting a second radar signal and receiving RF signals, where the second radar signal is offset in frequency from the first radar signal, and one or more processors. The one or more processors analyzes harmonic and intermodulation (IM) signals generated in response to the first radar signal and the second radar signal interacting with nonlinear characteristics in components of a RF device. The analyzing provides detection of the presence of the RF device and the determination of a location of the RF device regardless of whether the RF device is active or passive.

Abstract: Methods and apparatus for detecting the presence of electronic communications devices, such as cellular phones, are disclosed. In an exemplary method, a complex radio frequency stimulus is transmitted into a target area, and nonlinear reflection signals received from the target area are processed to obtain a response measurement. The response measurement is compared to a pre-determined filter response profile to detect the presence of a radio device having a corresponding filter response characteristic. In some embodiments, the pre-determined filter response profile comprises a pre-determined band-edge profile, so that comparing the response measurement to a pre-determined filter response profile comprises comparing the response measurement to the pre-determined band-edge profile to detect the presence of a radio device having a corresponding band-edge characteristic.

Abstract: A process for detecting the harmonic motion characterizing a desired target. An exemplary method includes generating a radar image of the target utilizing a pulse doppler radar. A plurality of matched filter signals are generated in the receiver, each matched filter signal corresponding to a doppler profile of harmonic acceleration for the desired target. The matched filter signals are generated by an array of matched filters, with each matched filter signal corresponding to a predetermined doppler profile. The received radar image is then correlated to the matched filter signals to detect the desired target.

Abstract: In one embodiment, an ultra wide band (UWB) radar includes: a substrate; a plurality of antennas adjacent the substrate, the plurality of antennas being arranged into a plurality of sub-arrays; an RF feed network adjacent the substrate, the RF feed network coupling to a distributed plurality of amplifiers integrated with the substrate, wherein the RF feed network and the distributed plurality of amplifiers are configured to form a resonant network such that if a timing signal is injected into an input port of the RF feed network, the resonant network oscillates to provide a globally-synchronized RF signal across the network; a plurality of pulse-shaping circuits corresponding to the plurality of sub-arrays, each pulse-shaping circuit being configured to receive the globally-synchronized RF signal from the network and process the globally-synchronized RF signal into pulses for transmission through the corresponding sub-array of antennas; and an actuator for mechanically scanning the UWB radar so that the pulse

Abstract: The system includes a transmitter, at least one detection system receiver, a modulated signal source, and a directional receive antenna. The transmitter emits a high power illuminating signal at a receive frequency of a target RF receiver to be detected. The high power illuminating signal is sufficient to cause the target RF receiver to generate harmonic emissions. At least one detection system receiver is used for detecting at least one harmonic frequency emitted by the target RF receiver. The modulated signal source is operatively associated with the transmitter to modulate the illuminating signal and for use as a reference to the detection system receiver such that the turn around time of the harmonic frequency emitted by the target RF receiver can be measured. A directional receive antenna is operatively associated with the detection system receiver for determining the angle to the target RF receiver.

Abstract: An acoustic tone at a predetermined frequency is detected after being reflected and modulated by an unknown moving object. Acoustic features are extracted from the reflected acoustic tone using acoustic spectral analysis. A dimensionality of the acoustic features is reduced, and the reduced dimensionality features are statistically classified to identify the object.

Abstract: Techniques to image life forms through obstructions and at long standoff ranges employ a radar system that simultaneously transmits a plurality of RF pulse trains having different transmission frequencies and receives returns of the RF pulse trains reflected from a life form target. The returns are processed to generate digital radar data associated with the transmission frequency of each RF pulse train. The digital radar data is segmented and averaged to generate a Doppler spectrum response associated with the transmission frequency of each RF pulse train. Target classification is performed using the Doppler spectrum responses to extract biometric data describing the life form target.

Abstract: The invention relates to a radar system which comprises: (a) at least two transmitting units for simultaneously, and in synchronization transmitting electromagnetic radiation in distinct frequencies f1, f2, f3 . . . towards a space of interest; and (b) at least one receiving unit tuned to a frequency of nf1+mf2+qf3 . . . , wherein n, m, q . . . being integers not equal to zero, for receiving a non-linear response of said radiation from objects located within the said space of interest, and wherein the system is characterized in that said transmitted pulses are narrow pulses having duration in the range of between about 1 nanoseconds and about 100 nanoseconds.

Abstract: The invention relates to a radar system which comprises: (a) at least two transmitting units for simultaneously, and in synchronization transmitting electromagnetic radiation in distinct frequencies f1, f2, f3 . . . towards a space of interest; and (b) at least one receiving unit tuned to a frequency of nf1+mf2+qf3 . . . , wherein n, m, q . . . being integers not equal to zero, for receiving a non-linear response of said radiation from objects located within the said space of interest.

Abstract: A radar target detection method in which an azimuth at which a target is located is detected on the basis of reception signals obtained through antenna elements of an array antenna by detecting a change in levels of spectrum peaks in an azimuth spectrum of reception signal intensities, calculating a level of correlation between the level change of each spectrum peak and a directivity pattern of the array antenna in an azimuth range corresponding to the spectrum peak, and determining an azimuth corresponding to one of the spectrum peaks having the highest corresponding correlation level to be the azimuth at which the target is located.

Abstract: A quadrature radar apparatus includes a quadrature signal generating unit, a plurality of coupler modules connected to the signal generating unit, an antenna unit receiving transmission signals from the coupler modules and a reception signal reflected from a target, one or more phase delay modules connected between one or more of the coupler modules and the antenna unit to delay the phases of the transmission and reception signals by 90 degrees, a leakage signal canceling unit combining the reception signals inputted from the antenna unit through the first and second coupler modules and removes the transmission leakage signal.

Abstract: The present invention is a system and method for detecting devices with receivers, such as explosive devices with receivers used to remotely detonate the explosive devices. The system for detecting devices may include a transmitter which transmits a signal causing saturation of a device whereby harmonic content is emitted by the device. Receipt of an emitted harmonic signal which is coherent to the transmitted signal may indicate the presence of a device. A distance between the system and the detected device may be determined by modulating a frequency of the transmitted signal and measuring the time period between transmission of the signal and receipt of a harmonic signal. Additionally, direction information may be determined which may allow identification of a location of the device based upon the distance information and direction information.

Abstract: Channel quality can be detected accurately in a wireless transmission system such as an HSDPA method. In the case of estimating a channel quality of a signal transmitted by a Code Division Multiple Access method and of estimating the channel quality in a system having a synchronization channel not orthogonal to a channel receiving data, a noise component of a desired channel is estimated; degree of a noise component caused by the synchronization channel is estimated with respect to the estimated noise; and a channel quality of a receiving channel is detected based on the estimated degree of the noise component.

Abstract: A pulsed radar system uses simultaneous multiple frequency spectral response of life form targets to classify target type and movements. In particular classifying movements from human and animals such as walking and breathing. Currently radar systems attempt to image targets with ultra high bandwidth (fine range resolution) and a large or synthetic aperture (SAR). These techniques slice up the scene into a three-dimensional radar picture. The radar picture data is again processed with target classifiers. Currently these classical techniques are beyond state-of-the-art at long standoff ranges. This new radar system will use multiple sparse lower bandwidth frequencies to provide life form classification imaging based on the spectral response. The lower bandwidth dramatically improves the data quality while the spectral ratios and correlations will resolve sparse frequency ambiguities for a new type of imaging radar.

Abstract: A method is presented for packet detection and symbol boundary location using a two-step sign correlation procedure. When the correlation crosses a threshold, a packet detection signal is generated to initiate processing of downstream blocks, and a symbol boundary location signal is generated for use in aligning data during processing.

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

Abstract: The number of times for averaging operation for averaging a correlation value of a received signal and a reference signal is properly controlled. When the correlation value is not averaged, since a lower limit value TH_A of a correlation level of a distribution of timings of which a path exists is larger than an upper limit value TH_B of a correlation level of a distribution of timings of which a path does not exist, the correlation value of a path is hidden by noise. Since the averaging operation is repeated until the relation of TH_A>TH_B is satisfied, the averaging operation is stopped when the relation is satisfied. The TH_A and TH_B are decided in accordance with RSCP and ISCP of a pilot channel and RSSI of a received base band signal.

Abstract: A method of Partial Parallel Interference Cancellation (PPIC) is provided for recursively eliminating the Multiple Access Interference from a received signal. Such method is to use a recursion way to eliminate all the Multiple Access Interference (MAI) one by one from the received signal. Moreover, the present invention is to take the output of the pre-stage as the input of the present stage with the recursion method so that we can use only one operating circuit to obtain the function the MAI eliminating.

Abstract: There is provided a radar system having an input amplitude correcting function in which even when a large reflection wave exceeding a dynamic range of an A/D converter is inputted, an RCS calculation without a time lag can be executed at high precision, high reliability, and low costs without using power amplification degree control such as an AGC circuit or the like. Harmonic peaks of each target peak of an FFT-processed frequency spectrum are detected. When the harmonics are detected, it is determined that the large reflection wave exceeding the dynamic range of the A/D converter has been inputted, and a lost input amplitude is corrected in accordance with a correction table showing a relation between the harmonic order and an input amplitude correction amount which have previously been recorded.

Abstract: To reduce the size, weight and cost of an interrogator which is included in an RFID system and required to have a high output power, the interrogator for transmitting a signal shares a radio wave source or a power supply with a portable wireless terminal such as a mobile phone or a portable communication device. For this purpose, a radio frequency transmitter signal is subjected to amplitude modulation by information to be transmitted to a transponder. Furthermore, part of the radio frequency transmitter signal extracted using a coupler is used to perform synchronous detection on a radio frequency receiver signal returned from the transponder, and data coming from the transponder are extracted.

Abstract: A radar includes a transmitter circuit, a receiver circuit, an antenna and a circulator. The receiver circuit includes a low-noise amplifier which amplifies a received signal fed from the antenna through the circulator. A local oscillator provided in the receiver circuit generates a local oscillator signal of which frequency is approximately half the frequency of the received signal, and the local oscillator signal is amplified by a buffer amplifier. An even harmonic mixer including an anti-parallel diode pair also provided in the receiver circuit as a frequency converter mixes the received signal output from the low-noise amplifier with the local oscillator signal output from the buffer amplifier to generate and output an intermediate frequency signal.

Abstract: A system and method for performing distance measurement using wireless signals. A time of flight calculation is enabled by an interrogating device that transmits an interrogation signal to a responding device, which returns a synchronized signal back to the interrogating device. The wireless signals between the interrogating device and the receiving device have a harmonic relationship. In one embodiment, a time shift of a received signal relative to a transmitted interrogation signal is determined based on a comparison of a first reference point on a signal representative of the transmitted interrogation signal and a second reference point on a signal representative of the received signal.

Abstract: A system and a method for monitoring a freight container are provided. The method includes the steps of generating a resonant spectrum representative of an initial condition of internal surfaces and contents of the freight container, and saving the resonant spectrum for future comparison purposes. The method further includes generating a second resonant spectrum and comparing the second resonant spectrum with the initial resonant spectrum to determine whether there has been any tampering with the freight container. The method also includes identifying the contents of the freight container and generating loading diagrams of the contents and using polarity configuration characteristics of the internal surfaces of said freight container to determine whether the contents have moved or been shifted during transport.

Abstract: A radar processor is disclosed for processing the radar return samples from a Doppler radar receiver to discriminate helicopter targets from fixed-wing targets. The radar processor defines the spectral components of the radar return components due to the helicopter rotor hub as the “signal” component; and the spectral components due to the target skin, ground clutter and white noise as the “noise” component. The radar processor implements the Neyman Pearson criterion to calculate a detection statistic. Whether the calculated detection statistic exceeds a threshold determines whether a “helicopter presents” or a “helicopter absent” target condition is declared. The radar processor utilizes helicopter rotor hub reflected signals, and requires only a few milliseconds on target, and may therefore be readily implemented by scanning surveillance systems.

Abstract: A varying magnetic field excites slight vibrations in an object and a radar sensor detects the vibrations at a harmonic of the excitation frequency. The synergy of the magnetic excitation and radar detection provides increased detection range compared to conventional magnetic metal detectors. The radar rejects background clutter by responding only to reflecting objects that are vibrating at a harmonic excitation field, thereby significantly improving detection reliability. As an exemplary arrangement, an ultra-wideband micropower impulse radar (MIR) is capable of being employed to provide superior materials penetration while providing range information. The magneto-radar may be applied to pre-screening magnetic resonance imaging (MRI) patients, landmine detection and finding hidden treasures.

Abstract: A system for providing the identification and tracking of motor vehicles that includes a probe device that transmits a radio frequency modulated signal to a transponder unit that is located within a vehicle registration tag of a vehicle. The transponder unit responds to the probe unit's request by transmitting its own radio frequency modulated signal containing any information requested by the probe device.

Abstract: A radar method of classifying generating or identifying helicopters, by generating a one-dimensional distance profile of the helicopter to be classified or to be identified by measuring the radar each of the helicopter fuselage, the radar echo of the rotor head of the main rotor and/or the radar echo of the main axis, and the radar echo of the rear rotor axis; determines the aspect angles in the azimuth and elevation directions relative to the axis of the radar antenna and the method also determines helicopter parameters from the measured radar echoes. The determined helicopter parameters and are compared with stored helicopter parameters for different helicopter types.

Abstract: A harmonic radar nonlinear junction detector system for detecting concealed weapons, electronics, and other man-made objects utilizing state-of-the art wireless technology, circuit fabrication, signal synthesis, and computer processing techniques to detect and characterize man-made objects possessing nonlinear junctions. The system transmits a pair of low power waveforms and a receiver within the system is coherently tuned to harmonics of the transmitted frequencies of the waveforms to detect man-made metal objects and electronics that contain non-linear junctions. The receiver is also capable of receiving inter-modulation products reflected from the man-made objects that are a result of using two incident signals. The system uses two signal sources generating user-definable waveforms of variable frequencies in order to provide enhanced discrimination and target identification abilities via the processing of returned inter-modulation products.

Abstract: An unwanted peak occurring due to an antenna sidelobe and an unwanted peak occurring due to a harmonic are eliminated in a radar apparatus. A peak from a target that can cause an unwanted peak is found based on the intensity of the peak, and a search is made for a peak having a predetermined positional relationship with the thus found peak. If such a peak is located, then it is determined whether the peak is a candidate for an unwanted peak, based on the difference between the intensity of the peak and the intensity of the main peak. If both of the paired peaks are determined as being candidates for unwanted peaks, it is determined that the peaks are unwanted peaks.

Abstract: An RF band receiver for concurrently monitoring a plurality of contiguous channels within the RF spectrum to unambiguously detect time-coincident signals. The receiver includes a plurality of transmission paths feeding a like number of digital, mixed-base code channels. Each mixed-base code channel includes a harmonic mixer, an IF amp, a plurality of bandpass-filters and a like plurality of detectors. The outputs of the detectors for each mixed-base code channel are fed to a frequency sorter whose output is a digital frequency word which indicates the frequency(s) of the received signal(s).

Abstract: A multi-stage processing system receives data from signals that indicate information related to scatterers, such as signals from a Doppler scanning system. The multi-stage processing system tracks allowed processing time for the data. The multi-stage processing system performs a first stage of processing for the data to generate first estimates of spectral moments for the signals. The multi-stage processing system performs additional stages of processing for the data as the allowed processing time permits and stops the additional stages of processing for the data when the allowed processing time expires. The additional stages of processing may comprise generating second estimates for at least some of the spectral moments. The additional stages of processing may use methods having increasing complexity and accuracy.

Abstract: An unwanted peak occurring due to an antenna sidelobe and an unwanted peak occurring due to a harmonic are eliminated in a radar apparatus. A peak from a target that can cause an unwanted peak is found based on the intensity of the peak, and a search is made for a peak having a predetermined positional relationship with the thus found peak. If such a peak is located, then it is determined whether the peak is a candidate for an unwanted peak, based on the difference between the intensity of the peak and the intensity of the main peak. If both of the paired peaks are determined as being candidates for unwanted peaks, it is determined that the peaks are unwanted peaks.

Abstract: A target classification method for radar systems wherein, in particular, jet aircraft, are classified in that the blade repetition rate and, in a further step, the number of blades, of an engine rotor wheel are determined and thus the type of engine is identified. Helicopters are classified by determining the blade repetition period of the primary or tail rotor.

Abstract: Circuit for stabilizing the spectral extent of a varying signal containing harmonically related frequency components and having particular utility in the spectral analysis of radar return for the purpose of target identification. The variable signal is written into a storage device at a fixed rate and read out with a variable time compression which is controlled by a discriminator circuit that is connected through a filter to receive one of the harmonic frequency components of the storage device output signal. Also included is signal conversion for digital storage with analog input and output signals.

Abstract: A method is described for detecting moving and/or stationary objects in the path of a vehicle, where the distance and velocity of the reflecting object are determined by using a radar sensor, where the frequency of the signal transmitted is modulated in the shape of a ramp according to a multi-ramp method, and some ramps have a lower slope in the frequency curve. The higher spectral components of the mixed signals from the ramps having the lower slope, which are to be assigned to a distance range of the reflecting object which is greater than the distance range belonging to the ramps having the greater slope, are used to determine the distance, speed and angle of objects.

Abstract: A multi-stage processing system receives data from signals that indicate information related to scatterers, such as signals from a Doppler scanning system. The multi-stage processing system tracks allowed processing time for the data. The multi-stage processing system performs a first stage of processing for the data to generate first estimates of spectral moments for the signals. The multi-stage processing system performs additional stages of processing for the data as the allowed processing time permits and stops the additional stages of processing for the data when the allowed processing time expires. The additional stages of processing may comprise generating second estimates for at least some of the spectral moments. The additional stages of processing may use methods having increasing complexity and accuracy.

Abstract: A police radar detector detects police radar signals in the X, K and wide Ka police radar bands and rejects interfering Ka band signals that are a higher harmonic of a nuisance source having a fundamental frequency adjacent to the X police radar bands. Each of the three police radar bands is separately swept in a first mixer stage with the resulting IF signal concurrently demodulated in two IF circuits. The first IF circuit detects signals that were received in the X, K and outer portions of the wide Ka band during respective sweeps. The second IF circuit detects nuisance signals adjacent to the X and K bands, and the inner portion of the wide Ka band during respective sweeps.