Abstract: A multi-chip MIMO radar system includes a plurality of transmitters and a plurality of receivers. Each of the pluralities of transmitters and receivers are arranged across a plurality of chips. The multi-chip MIMO radar system includes a central processor configured to receive data from the plurality of chips. The central processor is operable to combine the information from each radar chip to produce improved range detection and angular resolvability of targets.

Abstract: A radar device includes a transmit antenna radiating a modulation signal and a receive antenna receiving reflection waves from the modulation signal. The radar device also includes a mixer mixing the modulation signal and the received signal to output a beat signal, a calculation circuit judging presence or absence of an abnormality by using the beat signal, and a memory storing reference data and a threshold. The reference data indicates a phase component of a set frequency signal from a beat signal without necessarily any abnormality. The set frequency signal is generated from the modulation signal reflected on a surface of a housing located at a set distance from the radar device. The calculation circuit extracts a phase component from the beat signal and supplies information indicating the presence of an abnormality if the difference between the extracted phase component and the reference data is greater than the threshold.

Abstract: Radar transmitter includes a plurality of transmit antennas that transmit a plurality of transmission signals using a multiplexing transmission, and a transmission circuit. The transmission circuit applies phase rotation amounts corresponding to combinations of Doppler shift amounts and code sequences to the plurality of transmission signals. Each of the combinations of the Doppler shift amounts and the code sequences has at least one different from other combination. The number of multiplexes of the code sequence corresponding to at least one of the Doppler shift amounts in the combinations is different from the number of multiplexing of code sequences corresponding to the remaining Doppler shift amounts.

Abstract: Embodiments of the present disclosure utilizes the natural properties of RFI noise on a wireline link. Since differential RFI noise in the system has some correlation with the common mode noise on the cable, a replica of RFI noise can be regenerated by an adaptive filter based on information about the common mode noise. The replica RFI is subtracted from the equalizer output prior to the data decision circuitry or slicer. In this method, the system does not require expensive cable, nor does the equalizer suffer additional loss due to an RFI notch filter. Since RFI can be detected and mitigated, this information can also be coupled to safety systems to increase functional safety under high EMI conditions.

Abstract: Directional antennas comprising substantially identical radiation patterns separated in a horizontal plane by an index angle. A line of bearing to an emitter is determined by a ratio of the power level of an EM signal received by the directional antennas and comparing it to a lookup table to determine an angle off of the boresight of the directional antenna with the highest received power level of the EM signal toward the directional antenna with the second-highest received power level of the EM signal that the emitter of the EM signal is located.

Abstract: An image processing method configured to correct a captured image using a neural network includes a first step of determining an inversion axis for a partial image or a filter of the neural network according to a position in the captured image of the partial image that is part of the captured image, a second step of determining a positional relationship among pixels of color components in an image input to the neural network corresponding to the inversion axis, and a third step of generating a corrected image obtained by correcting an input image by processing, using the neural network, the input image generated from the captured image based on the positional relationship.

Abstract: Methods, systems, and apparatus, including computer programs encoded on computer storage media, for audio processing using neural networks. One of the systems includes multiple neural network layers, wherein the neural network system is configured to receive time domain features of an audio sample and to process the time domain features to generate a neural network output for the audio sample, the plurality of neural network layers comprising: a frequency-transform (F-T) layer that is configured to apply a transformation defined by a set of F-T layer parameters that transforms a window of time domain features into frequency domain features; and one or more other neural network layers having respective layer parameters, wherein the one or more neural network layers are configured to process frequency domain features to generate a neural network output.

Abstract: A weather radar system can be used as an enhanced vision sensor for providing an image on an electronic display during aircraft surface operations. The weather radar sensed image is representative of the external surroundings of the airport surface environment associated with radar returns received by the weather radar system. The radar returns are processed as a collection of radar measurements to determine a high resolution angle and range to a target, using beam sharpening techniques. When the radar image is combined with an image generated from an airport surface database, the combination or comparison of the two independently created images can be used to confirm the integrity of the positioning and attitude source along with the accuracy of the airport surface database.

Abstract: A method for processing detection and range signals using a digital signal processor generates an interstitial filter that overlaps two adjacent baseline filters of filter bank. The interstitial filter is generated from data outputs of the two adjacent baseline filters using computations that are much simpler than those used to generate baseline filters. The inclusion of interstitial filters in the filter bank improves the resolution and signal to noise ratios of the filter bank.

Abstract: A structure evaluation apparatus has an acquisitor and an evaluator. The acquisitor acquires a distribution that represents a distribution of strength of a reflected wave obtained by an electromagnetic radar scan to a reinforced concrete which comprises concrete and a material other than concrete. The evaluator calculates similarity, with reference to a reference region including the material in the distribution, of other regions including the material than the reference region in the distribution.

Abstract: The methods and systems for amplify-and-forward (in-band) relaying relate to beamforming techniques including receive and transmit beamforming for reducing self-interference, and improving Signal-to-Noise Ratio (SNR), or Signal to Interference plus Noise Ratio (SINR), of an incoming signal (to be relayed). The incoming signal is amplified and retransmitted simultaneously with the incoming signal, and over the same frequency band as that of an incoming signal.

Abstract: Systems and methods for a radar system to produce a radar image of a region of interest (ROI). A set of antennas to transmit radar pulses to the ROI and to measure a set of reflections from the ROI corresponding to the transmitted radar pulses. A processor acquires an estimate of the radar image, by matching the reflections of the ROI measurements for each antenna. Determine a set of shifts of the radar image. Wherein each shift corresponds to an antenna, and is caused by an uncertainty in a position of the antenna. Update the estimate of the radar image, based on the determined set of shifts of the radar image. Wherein for each antenna, the estimate of the radar image is shifted by the determined shift of the radar image corresponding to the antenna, that fits the reflections of the ROI measurements of the antenna.

Abstract: In the proposed low complexity technique a hierarchical approach is created. An initial FFT based detection and range estimation gives a coarse range estimate of a group of objects within the Rayleigh limit or with varying sizes resulting from widely varying reflection strengths. For each group of detected peaks, demodulate the input to near DC, filter out other peaks (or other object groups) and decimate the signal to reduce the data size. Then perform super-resolution methods on this limited data size. The resulting distance estimations provide distance relative to the coarse estimation from the FFT processing.

Abstract: A method for operating a transmit-receive point (TRP) includes generating a different spatial domain to time domain transform (STT) symbol for each antenna element in an antenna array, and transmitting the STT symbols using the antenna array to sweep a beam along a first plane in the time domain.

Abstract: A method for operating a transmit-receive point (TRP) includes generating a different spatial domain to time domain transform (STT) symbol for each antenna element in an antenna array, and transmitting the STT symbols using the antenna array to sweep a beam along a first plane in the time domain.

Abstract: An image of a region of interest (ROI) is generated by a radar system including a set of one or more antennas. The radar system has unknown position perturbations. Pulses are transmitted, as a source signal, to the ROI using the set of antennas at different positions and echoes are received, as a reflected signal, by the set of antennas at the different positions. The reflected signal is deconvolved with the source signal to produce deconvolved data. The deconvolved data are compensated according a coherence between the reflected signal to produce compensated data. Then, a procedure is applied to the compensated data to produce reconstructed data, which are used to reconstruct auto focused images.

Abstract: An aircraft system includes a processing unit configured to identify an airport marker during a surface operation at an airport. The processing unit is further configured to automatically generate a reporting message based on the airport marker at a predetermined location relative to the airport marker. The aircraft system further includes a communications unit coupled to the processing unit and configured to send the reporting message.

Abstract: A locator assembly is provided. The locator assembly includes an article of wear and a location sending device embedded in the article of wear. A bio-related electric generator is connected to the location sending device for providing power for the location sending device. A system for locating a person and a locating method are also provided.

Abstract: Provided are a vehicle approach detection device and a vehicle approach detection method that are capable of detecting an approach of another vehicle without installing a dedicated device on a road. At least one of a vehicle surrounding video for showing an observed area (for example, road surface) used to observe irradiation light (for example, headlight beam emitted from a headlight of another vehicle) from another vehicle and a vehicle surrounding environmental sound is detected as vehicle external information, and it is determined based on the detected vehicle external information whether or not another vehicle is approaching an own vehicle.

Abstract: A method includes receiving from multiple transducers respective signals including reflections of a transmitted signal from a target. An image of the target is produced irrespective of sparsity of the received signals, by computing transducer-specific frequency-domain coefficients for each of the received signals, deriving, from the transducer-specific frequency-domain coefficients, beamforming frequency-domain coefficients of a beamformed signal in which the reflections received from a selected direction relative to the transducers are emphasized, and reconstructing the image of the target at the selected direction based on the beamforming frequency-domain coefficients.

Abstract: One or more systems and methods for a cell based hybrid resistance and capacitance (RC) extraction are provided. The method includes generating a layout for a semiconductor arrangement, performing a three-dimensional (3D) RC extraction on a target unit cell to obtain a 3D RC result including a coupling capacitance between unit cells, generating a 3D RC netlist based upon the 3D RC result, performing a 2.5 dimensional (2.5D) RC extraction on a peripheral cell to obtain a 2.5D RC netlist, and combining the 3D RC netlist with the 2.5D RC netlist to create a hybrid RC netlist for the layout. In some embodiments, the hybrid RC netlist is generated by stitching the coupling capacitance for at least one of the target unit cell, a repeating unit cell, or the peripheral cell together. In some embodiments, the 3D RC result for the target unit cell is stitched to the repeating unit cell.

Abstract: A high performance broadband antenna for backpack and helmet application allowing data, video, and voice transmission between parties. The antenna consists of a pair of triangle shaped elements which are configured to stick on a backpack surface or place over a helmet with a coaxial cable connecting a radiating structure to the communication equipment on the body. A metal shielding performs as a ground plane and also acts as a protectant from radiation hazards to the head or body areas. The antenna is made with materials that conform to the shape of a helmet or stick directly onto a backpack surface. This design can function under multiple frequencies on UHF and S bands; its placement on a helmet receives less Interference from Its surroundings.

Abstract: According to one embodiment, a weather radar apparatus includes an antenna apparatus, a signal processing apparatus, a data converter, a forecasting unit, a state determination unit, and radar controller. The antenna apparatus radiates a radar pulse and receives a reflection pulse. The signal processing apparatus calculates a reception intensity, a Doppler speed, and a speed width. The data converter calculates rainfall intensity data and wind direction/speed data. The forecasting unit generates forecasting data based on the rainfall intensity data and on the wind direction/speed data. The state determination unit generates an observation sequence. The radar controller controls the antenna apparatus in accordance with the observation sequence.

Abstract: A method of eliminating spurious echoes in SAR imaging comprises a step Etp1 of defining the SAR imaging parameters, a step Etp2 of calculating the spectrum of the signal received, in each distance bin, of a zone of interest 51, a step Etp3 of filtering the spectra in each distance bin, a step Etp4 of SAR imagette 51 formation and a step Etp5 of concatenating the SAR imagettes 51 to form the final SAR image.

Abstract: A radar device includes a signal generator that generates an intermittent signal having a prescribed signal width and signal interval, a transmission signal position adjuster that outputs a transmission signal while adjusting positions of the intermittent signal on the time axis, an RF transmitter that transmits the transmission signal, an RF receiver that receives a reception signal including reflection waves reflected from an object in a measurement subject space, an AD converter that converts the reception signal into a digital signal, and an object detector that detects the object based on the reception signal. The transmission signal position adjuster outputs a transmission signal in which positions of respective signal units of the intermittent signal on the time axis are adjusted in units of a time adjustment amount that is shorter than a sampling interval of the AD converter.

Abstract: A radar sensor and a method of detecting an object by using the same are provided. The method includes: receiving at least one radar signal reflected from the object; converting the received at least one radar signal to at least one signal in a frequency domain; accumulating the converted at least one signal for a predetermined time and extracting at least one feature from the accumulated at least one signal; and identifying the object by comparing the extracted at least one feature with at least one reference value stored in a database.

Abstract: A method for processing return radar waveforms in response to transmitted radar waveforms. The method includes receiving, with a processor, a return radar waveform having a Doppler shift larger than Doppler tolerance. The method also includes separating, with the processor, the return radar waveform into a plurality of shortened waveforms. The method also includes compressing, with the processor, each of the plurality of shortened waveforms with a shortened form of the return radar waveform. The method also includes summing, with the processor, the plurality of compressed, shortened waveforms by computing a Doppler Fourier transform for each radar range bin of the return radar waveform using the plurality of compressed, shortened waveforms.

Abstract: An electronic scan type radar device which uses a high resolution performance processing to estimate directions of arrival of radio waves, wherein powers of arrival waves received for targets are accurately calculated, that is, a vehicle-mounted radar device utilizing electronic scan which uses a predetermined angle estimation system to estimate directions of arrival of reflected waves, comprising finding mode vectors for angles calculated from the receive signals of the antennas, decomposing a vector of the receive signals into directions of the mode vectors, and defining the lengths of the decomposed vectors the receive powers of the reflected waves arriving from the targets. Due to this method, even if there are targets, it is possible to accurately calculate the powers of the arrival waves, whereby pairing is accurately performed, the precision of detection of targets is improved, and erroneous operation of a vehicle-mounted radar device utilizing electronic scans is prevented.

Abstract: This invention relates to sense through the wall radar. A main channel of a radar system (12) is operated at a frequency capable of penetrating opaque barriers such as the wall (24) of a building (22) to sense targets (16) therein. The main channel performance may be impaired by multipath interference, i.e., radar returns resulting from targets (20) outside the building (22) illuminated by reflection from the wall (24). A guard channel of the radar, operating at a higher frequency which does not penetrate the wall (24), is used to identify targets (20) outside the building (22) and suppress the multipath interference they produce in the main channel.

Abstract: A processing method for radar signal with dual pulse repetition frequency, comprising: generating a first transmission signal and a second transmission signal, and perform a transmission process; reflecting a first echo signal and a second echo signal from an object, and converting the first transmission signal and the second transmission signal to a frequency domain information by using 2D (Two Dimension) fast Fourier transform (FFT); and filtering noise in the frequency domain information, and performing a calculation program by using a algorithm to obtain Doppler shift of the object. Thereby, the processing method of the present invention can overcome the bad operation ability of the lower hardware and advance the radar target detection speed restrictions.

Abstract: An instrument (100) is provided according to an embodiment of the invention. The instrument (100) includes an interface (101) configured to receive a Doppler measurement signal and a processing system (112) coupled to the interface (101) and receiving the Doppler measurement signal. The processing system (112) is configured to generate a two-sided velocity spectrum including a plurality of discrete frequency bins from the Doppler measurement signal, with the two-sided velocity spectrum distinguishing spectral elements, and process one or more velocity spectrum bin pairs against a plurality of local gate thresholds, with the one or more velocity spectrum bin pairs being substantially symmetrically located about one or more carrier wave bins and wherein each velocity spectrum bin pair is processed against a corresponding local gate threshold of the plurality of local gate thresholds.

Abstract: The present invention uses a Single Instruction Multiple Data (SIMD) architecture to form real time 3D radar images recorded in cylindrical near field scenarios using a wavefront reconstruction approach. A novel interpolation approach is executed in parallel, significantly reducing the reconstruction time without compromising the spatial accuracy and signal to noise ratios of the resulting images. Since each point in the problem space can be processed independently, the proposed technique was implemented using an approach on a General Purpose Graphics Processing Unit (GPGPU) to take advantage of the high performance computing capabilities of this platform.

Abstract: In a radar apparatus, a peak extractor performs frequency analysis on a beat signal to obtain a frequency spectrum for each of first and second detection modes based on the beat signal for a corresponding one of the first and second detection modes. The peak extractor extracts a plurality of first peak-signal components from the frequency spectrum obtained for the first detection mode, and a plurality of second peak-signal components from the frequency spectrum obtained for the second detection mode. A determiner compares each of the plurality of first peak-signal components with a corresponding one of the plurality of second peak-signal components to deter mine whether a noise is included in the beat signal according to a result of the comparison.

Abstract: Provided is an object identification device and a method for the same that are capable of identifying a three-dimensional object and a road surface static object, irrespective of situations. The object identification device identifies an object, based on a transmission signal and a reflection signal caused by the object reflecting the transmission signal. The object identification device includes: a measurement section configured to measure at least one of the relative distance and the relative velocity with respect to the object; an intensity detection section configured to detect the intensity of the reflection signal; and an object identification section configured to identify the object which can be an obstacle object, based on at least one of the relative velocity and the variation in the relative distance, and on the variation in the intensity.

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 apparatus includes an extendable wand, and a sensor head coupled to the wand. The sensor head includes a continuous wave metal detector (CWMD) and a radar. When the wand is collapsed, the wand and the sensor head collapse to fill a volume that is smaller than a volume filled by the sensor head and the wand when the wand is extended. Frequency-domain data from a sensor configured to sense a region is accessed, the frequency-domain data is transformed to generate a time-domain representation of the region, a first model is determined based on the accessed frequency-domain data, a second model is determined based on the generated time-domain representation, the second model being associated with a particular region within the sensed region, and a background model that represents a background of the region is determined based on the first model and the second model.

Abstract: An FMCW radar sensor system is described having an antenna covered by a radome, a mixer for mixing a frequency-modulated transmission signal with a signal received by the antenna, a device for recording the mixed product of the mixer as a time-dependent signal, a device for calculating the spectrum of the time-dependent signal, and a device for detecting a reflecting coating on the radome, characterized in that the device for detecting the reflecting coating is configured for analyzing the time-dependent signal and for determining the extent of reflection on the radome based on the amplitude of this signal.

Abstract: There is provided a radar apparatus for detecting a target. A detection signal generating unit generates detection signals of the target based on transmission and reception waves of antennas. A detection signal processing unit performs frequency analysis on the detection signals to extract signal components of the target, and performs a predetermined process on the signal components to calculate at least one of a distance to the target, a relative speed to the target, and an orientation of the target. The detection signal generating unit includes a filter unit for giving changes to the detection signals in a frequency bandwidth higher than Nyquist frequency which is a half a sampling frequency. The detection signal processing unit acquires the signal components from the detection signals to which the filter unit gives the changes to determine whether the signal components are generated by replication due to the Nyquist frequency.

Abstract: A device for radar applications includes a computing engine, a radar acquisition unit connected to the computing engine, a timer unit connected to the computing engine, a cascade input port, and a cascade output port. The cascade input port is configured to convey an input signal to the computing engine and the cascade output port is configured to convey an output signal from the computing engine. Further, an according system, a radar system, a vehicle with such radar system and a method are provided.

Abstract: A system, method, and apparatus for radar pulse detection using a digital radar receiver are disclosed herein. In electronic warfare (EW), radars operate in an environment with highly dense electronic waveforms. As a result, the radars may receive thousands or millions of radar pulses every second. To detect and sort out radar pulses emitted from different radars is a challenging problem in electronic warfare. The present disclosure teaches a radar pulse detection system that utilizes digital channelization and joint-channel detection techniques to detect and separate radar pulses that are sent from different radar emitters. The main features of the present disclosure are: 1.) a digital channelization technique to separate radar pulses from their mixtures; 2.) a multi-channel detection technique to detect radar pulses; and 3.) an innovative technique to separate overlapped radar pulses.

Abstract: Systems and methods for automatically determining a noise threshold are provided. In one implementation, a system comprises: an antenna configured to gather data about a surrounding environment; a processing unit configured to remove samples representing target data from the gathered data; to estimate the noise floor from the gathered data with the removed target data; and to determine a noise threshold from the estimated noise floor; and a memory device configured to store the estimated noise floor.

Abstract: A processing method for radar signal with dual pulse repetition frequency, comprising: generating a first transmission signal and a second transmission signal, and perform a transmission process; reflecting a first echo signal and a second echo signal from an object, and converting the first transmission signal and the second transmission signal to a frequency domain information by using 2D (Two Dimension) fast Fourier transform (FFT); and filtering noise in the frequency domain information, and performing a calculation program by using a algorithm to obtain Doppler shift of the object. Thereby, the processing method of the present invention can overcome the bad operation ability of the lower hardware and advance the radar target detection speed restrictions.

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: The present invention relates to a signal transmitting apparatus, a method thereof, and an inverse fast Fourier transform (IFFT) apparatus for a signal transmitting apparatus. A signal transmitting apparatus according to an embodiment of the present invention receives data, and performs inverse fast Fourier transform (IFFT) on the data on the basis of a twiddle factor for shifting output data by the size of a cyclic prefix. In addition, the signal transmitting apparatus sequentially stores data corresponding to the size of the cyclic prefix starting with initial data among the transformed data, and generates an OFDM symbol on the basis of the stored data and the transformed data. According to the embodiment of the present invention, it is possible to efficiently reduce a time delay and a memory use amount when a cyclic prefix is added at a transmitting end, without changing the size of hardware and power consumption.

Abstract: A method of detecting movement includes using a radar sensor to monitor a space, and receiving an output signal from the radar sensor. A Fourier transform is performed on the output signal to produce a frequency domain signal spectrum. The frequency domain signal spectrum is transformed into an acoustic domain signal. It is decided whether the output signal is indicative of movement of a predetermined object or a non-human animal dependent upon at least one feature of the acoustic domain signal and at least one spectral feature of the signal spectrum.

Abstract: Described are computer-based methods and apparatuses, including computer program products, for radar data processing. In some examples, the method includes determining a plurality of substantially equally spaced frequency intervals within radar data based on an interval size; transforming parts of the radar data within each of the plurality of substantially equally spaced frequency intervals; determining a magnitude of each of the transformed parts of the radar data; and summing the magnitude for each of the transformed parts of the radar data to form adaptive radar data. The adaptive radar data can have a higher signal-to-noise ratio than the radar data.

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: A passive radar device includes: a pulse-by-pulse range compression unit executing cross-correlation processing between received signals of a direct wave and scattered wave on each of pulses divided by a direct-wave reception unit and a scattered-wave reception unit, and calculating a pulse-by-pulse range profile; a block-by-block Doppler processing unit calculating a first Doppler frequency spectrum by executing pulse-direction Fourier transform in block units each grouping plural pulses; a Doppler frequency cell-associated range migration compensation unit compensating a range-direction movement amount with respect to the first Doppler frequency spectrum on a Doppler-frequency-cell-by-Doppler-frequency-cell basis and on a block-by-block basis; and a block-direction Doppler processing unit calculating a second Doppler frequency spectrum by executing block-direction Fourier transform on an output from the Doppler frequency cell-associated range migration compensation unit.

Abstract: An apparatus for detecting a cavity comprising a signal receiver, a signal analyzer and a threshold excedent determination processor. The signal receiver receives a reflected signal resulting from an interaction of multi-frequency irradiating signal(s) with at least one cavity. The irradiating signal may include an electromagnetic or acoustic signal above a cavity dependent cutoff frequency with a randomized spectral component. The signal analyzer computes cavity detecting statistic(s) of the reflected signal. The cavity detecting statistic(s) may include an autocorrelation function. The autocorrelation function may be a Fourier transform of the power spectral density of the reflected signal. The threshold excedent determination processor generates a notification when cavity detecting statistic(s) exceed a threshold. The threshold may include a multi-variable function. The cavity may be the bore of a weapon. The apparatus may be configured to determine the bearing from the cavity to the apparatus.

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.