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 system capable of monitoring an area and detecting a disturbance with the area. The system has a plurality of ultra-wide band radio frequency tags, each of the tags including a digital signal processing module configured to monitor changes in radio frequency multipath properties of received packets transmitted by at least one other of the tags. Changes in the radio frequency multipath properties may be caused by a disturbance indicative of an object in the vicinity of the tags. A corresponding method is also disclosed.

Abstract: A system and method for pseudo real time collection of receive signal data in a single- or multi-channel ground penetrating radar. Each channel transmits electromagnetic impulses into a medium under test during each of a plurality of runs over the medium. Run receive signals are received in response to the transmitted impulses. Each run receive signal is sampled multiple times at a run sample rate. The sample points of each run are delayed by delay sequences with respect to the sample points of the other runs. The sample points of the individual runs are stored as a composite set of sample points representative of a receive signal sampled at an effective sample rate equal to a multiple of the run sample rate where the multiple is the number of runs.

Abstract: An anti-jamming system includes a tunable negative jamming signal feedback loop for feedback suppression of a received jamming signal. The system includes a zero IF phase locked loop (PLL) jamming signal receiver having a synchronous demodulator and a phase detector. A VCO is included in the PLL, as well as a phase detector and a loop filter. A replica jamming signal generator includes a tracking modulator with a baseband signal input coupled to an output of a synchronous demodulator in the receiver and a carrier input provided by the VCO. An output of the tracking modulator is negatively fed back to the input of the receiver to suppress the jamming signal in the received input.

Abstract: Embodiments of synthetic aperture radar systems for mapping Doppler frequency to cross-range to form bistatic inverse synthetic radar images of airborne targets.

Abstract: A filter which highly attenuates CW signals within specified frequency bands while allowing baseband pulses to pass therethrough with relatively low attenuation is provided. The filter comprises a main transmission line and stub transmission lines that are coupled in parallel relationship with the main transmission line. Each of the stub transmission lines is terminated with a short circuit or other appropriate impedance and is of such a length that a pulse coupled thereto from the main transmission line and reflected from the terminating impedance will arrive at the coupling plane with the main transmission line after the pulse propagating on the main transmission line has completely passed the coupling plane, thus eliminating the possibility of cancellation of any portion of the propagating pulse.

Abstract: The invention refers to an RF front-end (100) adapted to receive or transmit signals located in at least two separated frequency bands (100) comprising an input and an output and further comprising a first phase shifter (5) coupled to the input of the RF front-end (100); a second phase shifter (6) coupled to the output of the RF front-end (100); the first phase shifter (1) being coupled to the second phase shifter (2) via a first amplifier (3) and second amplifier (4), respectively.

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 is provided. A first edge on a first gating signal is generated, and a local oscillator and a shared clocking circuit with the first edge on the first gating signal. A second edge on a second gating signal is generated following the first edge on the first gating signal, and a receiver circuit is activated with the second edge on the second gating signal, where the receiver circuit includes a mixer. A transmit pulse following the first edge on the first gating signal is generated with the transmit pulse having a third edge. A switch that short circuits outputs of the mixer is then released following the later of the third edge of the transmit pulse and a delay.

Abstract: A pulse transmission controller generates transmission timing signals for a high-frequency radar transmission signal in every transmission cycle. A transmission phase shifter gives a transmission signal generated by a modulator phase shifts each corresponding to a transmission cycle on the basis of the transmission timing signals generated at intervals that are equal to the transmission cycle. A reception phase shifter gives a reception signal that is output from an A/D converter reception phase shifts that are opposite in direction to the respective transmission phase shifts given by the transmission phase shifter on the basis of the transmission timing signals generated at intervals that are equal to the transmission cycle.

Abstract: The invention relates to environmental characterization on the basis of an Ultra Wide Band (UWB) radiofrequency communication network. Pulses are emitted and the waveform received is compared with predicted waveforms corresponding to well determined interactions between the wave and its environment. The comparison is done by searching for maximum temporal correlation. The interactions can be notably reflections of the wave on walls or obstacles. The deformations are very dependent on the nature of the materials and directions in which the pulses are emitted and received. If predicted waveforms are stored for various pairs of direction of emission and of reception, it is possible through these correlation operations to find where a wall which gave rise to a reflection is situated.

Abstract: Systems and methods for protecting an airborne platform against collisions are provided. One system includes FMCW radar sensors including transmitting antennae, means for receiving signals from echoes and for processing and digitizing same, and means for sending a central unit data representing said digital signals via a dedicated point to point link. The central unit includes means for processing said data to detect obstacles, means for calculating parameters for each obstacle including its radial velocity, distance range and azimuth, and means to transmit an avionic system of said platform data representing said detected obstacles and parameters. The system further includes means for guaranteeing that said emitted signals are shifted in time to create a shift in frequency guaranteeing that the radar sensors operate in the whole frequency band without perturbing each other.

Abstract: There are provided an ultra-wideband radar imaging system comprising an antenna with at least one receiver and a plurality of transmitters operating in multi-static mode, method of operating thereof and volume visualization unit to be used in conjunction with the multi-static ultra-wideband radar imaging system. The method comprises: receiving by said at least one receiver a plurality of signals, each respectively representing return data in a channel associated with the receiver and one of the transmitters among said plurality of transmitters, thus giving rise to a plurality of spatial data channels; among said plurality of spatial data channels selecting data channels for further processing; and providing volume visualization by processing data corresponding merely to the selected spatial data channels.

Abstract: A radar sensor for a motor vehicle has at least one antenna arrangement for transmitting and receiving radar signals and a controller for controlling the operation of the antenna arrangement. The controller evaluates the received radar signals. The controller also operates the antenna arrangement to transmit and/or receive messages in a car-to-car communication.

Abstract: A method of detecting an abnormal driving includes receiving a RF signal transmitted from a vehicle in front; performing digital down conversion on the RF signal to obtain a baseband digital signal; performing frequency shift detection on the baseband digital signal to obtain frequency shift between the received RF signal and the RF signal transmitted from the vehicle in front; and determining that the abnormal driving condition in front exists response to determining that the frequency shift has reached a set threshold.

Abstract: A radar device capable of removing noise signals before digital conversion and detecting an object with high precision by a simple configuration is provided. In a transmitting RF unit 110, a signal switch 141 is switched so that the noise signal generated by the operation of a first switch 111 passes through a signal delaying device 142. The signal switch 141 is switched so that the noise signal generated by the operation of a second switch 112 passes through a signal delaying device 143. Furthermore, the signal switch 141 is switched so that a baseband pulse signal obtained when the first switch 111 and the second switch 112 are operated at the same time passes through a signal delaying device 144. In a signal synthesizer 145, synthesizing is carried out so that the noise signals mixed in pulse signals are cancelled out.

Abstract: This invention relates to capturing and processing the full bandwidth of an Ultra-Wideband (UWB) signal. An incoming UWB signal is processed in two different analog signal bands in parallel and their magnitudes summed to facilitate a Field programmable gate array (FPGA) processing of the entire UWB bandwidth to minimize digital implementation loss and promote a higher range.

Abstract: A vehicle remote function system is provided for determining a location of a fob relative to a vehicle. The system includes a controller adapted to be mounted in the vehicle and configured for communication with antennas mounted at different vehicle locations, the controller for use in determining the location of the fob based on ultra-wide band wireless signals transmitted between the antennas and the fob. The controller is configured to locate the fob within one of multiple three-dimensional zones, one of the zones configured to have a non-spherical shape. A method is also provided for use in a vehicle remote function system, the method for determining a location of a fob relative to a vehicle. The method includes transmitting ultra-wide band wireless signals between the vehicle and the fob, and determining the location of the fob within one of multiple three-dimensional zones, one of the zones having a non-spherical shape.

Abstract: A radar apparatus includes: a transmission circuit; a reception circuit; a Doppler filter that discriminates baseband signals per distance and per Doppler frequency corresponding to the speed of an object; a threshold processing unit group that removes unwanted signals from output signals of the Doppler filter; and an estimation unit that estimates a position and speed of the object from the output signals removed of the unwanted signals. The threshold processing unit group includes threshold processing units corresponding to respective discriminated Doppler frequencies. Each threshold processing unit calculates a threshold value for a corresponding Doppler frequency using a peak value of the output signals in a range of distance corresponding to an object detection area, and determines output signals in the range that are no greater than the threshold value to be the unwanted signals.

Abstract: Systems and methods are described herein for determining the presence of radar signals within the 5 GHz band using an active communications channel and a portion of the channels adjacent to the active channel. The access point radio may collect the bandwidth of the active and adjacent channels concurrently to avoid having to tune to each channel separately. Further, the radar scanning and a portion of the active channel processing may be completed simultaneously to improve access point utilization.

Abstract: A radar system includes at least one transmit array comprising a plurality of metamaterial elements. The radar system further includes at least one near-field stimulator for inputting electromagnetic signal to the transmit array so that a sub-wavelength target is illuminated with an electromagnetic wave.

Abstract: A surveillance system includes a multi-propeller aircraft having a main propeller and a plurality of wing unit propellers; a housing that houses the main propeller and the wing unit propellers; an ultra-wideband (UWB) radar imaging system; a control system for controlling flight of the multi-propeller aircraft from a remote location; and a telemetry system for providing information from the ultra-wideband (UWB) radar imaging system to the remote location. A method includes: remotely controlling flight of the aircraft using a main propeller and a plurality of wing unit propellers with airflow from the main propeller to the wing unit propellers for lift and propulsion; operating an ultra-wideband (UWB) radar imaging system from the aircraft; and transmitting information from the UWB radar imaging system to a display at a location remote from the aircraft.

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: Systems and methods involve generating a baseband signal, up-converting the baseband signal to a radar signal frequency, filtering a lower sideband of the up-converted signal, and transmitting the filtered up-converted signal. Systems and methods also involve receiving a return signal, down-converting the return signal using a signal having a frequency offset from the up-converted signal, filtering the upper sideband of the down-converted return signal, and producing a baseband return signal.

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 analogue isolator connected to said antenna arrangement, said transmitter, and said receiver. Said analogue 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: Ultra wideband radar motion sensors strategically placed in an area of interest communicate with a wireless ad hoc network to provide remote area surveillance. Swept range impulse radar and a heart and respiration monitor combined with the motion sensor further improves discrimination.

Abstract: A system for controlling an active electronically scanned array (AESA) antenna, which enables the AESA antenna to switch rapidly between different antenna states, includes memories (38) connected to a common address bus (40). Each memory (38) is also connected to a digitally controlled RF signal transmission block (32) within the AESA antenna, and stores digital control words for the digitally controlled RF signal transmission block (32). When a new address is provided on the address bus (40), each memory (38) outputs a new digital control word to its respective digitally controlled RF signal transmission block (32), causing a change in the state of the AESA antenna.

Abstract: One embodiment is directed to an aircraft position report system. The system comprises a satellite, an aircraft position reporting receiver mounted on the satellite, an antenna element mounted on the satellite, and an antenna interface mounted on the satellite. The aircraft position reporting receiver receives aircraft position reports through the antenna element by associating a spot beam with a narrow coverage area. The aircraft position reports are derived from a signal produced by the antenna element. The antenna interface changes the narrow coverage area associated with the spot beam to receive aircraft position reports from a wide coverage region within a reporting period. In one exemplary embodiment, the antenna interface mechanically steers the spot beam for each receiver to one of the narrow coverage areas. In another exemplary embodiment, the antenna interface electronically steers the spot beam for each receiver to one of the narrow coverage areas.

Abstract: An ultra-wideband (UWB) radar transmitter apparatus comprises a pulse generator configured to produce from a sinusoidal input signal a pulsed output signal s having a series of baseband pulses with a first pulse repetition frequency (PRF). The pulse generator includes a plurality of components that each have a nonlinear electrical reactance. A signal converter is coupled to the pulse generator and configured to convert the pulsed output signal into a pulsed radar transmit signal having a series of radar transmit pulses with a second PRF that is less than the first PRF.

Abstract: A method of surveying the condition of an underground enclosure including the steps of: (a) positioning at least one transmitter/receiver unit (including an antenna) within an underground, substantially nonconductive enclosure, such that a substantial air gap exists between the antenna and the inner wall of the enclosure; (b) transmitting an ultra wideband (UWB) signal toward at least a portion of the inner wall; and (c) processing the return signal in order to identify the interface between the soil and a region of conductivity different from the soil.

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: 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: A system includes a multi-system approach to detecting concealed weapons and person borne improvised explosive devices (PBIED). A first and second radar system operate at different center frequencies to provide, respectively, isolation of a target of interest from clutter and fine detail information on the target, such as whether the target is a living person, whether a concealed object may be present, material composition of the object, and shape, size, and position of the target relative to the system. Circular polarized radar beam may be used to distinguish a suspect object from within a crowd of people. Radar image of the object may be overlaid on visual image of a person carrying the object. Radar tracking of the object is coordinated with visual tracking of the target provided by a camera system, with visual display and tracking of the target overlaid with the radar information.

Abstract: Anti jamming system comprising a tunable negative jamming signal feedback loop for feedback suppression of a received jamming signal, including an receiver receiving an jamming signal followed by a replica jamming signal generator for generating an replica jamming signal. The receiver comprising a zero IF PLL receiver having a synchronous demodulator and a phase detector, signal inputs thereof being coupled to said input means and carrier inputs coupled to in-phase and phase quadrature oscillator outputs, respectively, of a local voltage controlled oscillator (VCO), said VCO receiving a tuning control signal for tuning the zero IF PLL receiver at the carrier frequency of the jamming signal. The VCO is included in a phase locked loop (PLL) comprising subsequent to the VCO, said phase detector and a loop filter.

Abstract: Anti jamming system comprising a tunable negative jamming signal feedback loop for feedback suppression of a received jamming signal, including a receiver receiving an jamming signal followed by a jamming signal replica generator for generating an replica jamming signal. The receiver comprising a zero IF PLL jamming signal receiver having a synchronous demodulator and a phase detector, signal inputs thereof being coupled to said input means and carrier inputs coupled to in-phase and phase quadrature oscillator outputs, respectively, of a local voltage controlled oscillator (VCO), said VCO receiving a tuning control signal for tuning the zero IF PLL jamming signal receiver at the carrier frequency of the jamming signal. The VCO is included in a phase locked loop (PLL) comprising subsequent to the VCO, said phase detector and a loop filter.

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: 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 homodyne motion sensor or detector based on ultra-wideband radar utilizes the entire received waveform through implementation of a voltage boosting receiver. The receiver includes a receiver input and a receiver output. A first diode is connected to the receiver output. A first charge storage capacitor is connected from between the first diode and the receiver output to ground. A second charge storage capacitor is connected between the receiver input and the first diode. A second diode is connected from between the second charge storage capacitor and the first diode to ground. The dual diode receiver performs voltage boosting of a RF signal received at the receiver input, thereby enhancing receiver sensitivity.

Abstract: The present invention comprises a method for through the wall radar imaging. An impulse synthetic aperture radar system transmits short, ultra-wideband carrierless microwave pulses at an obstacle behind which a target of interest is located. The return signals are received, stored and analyzed. Portions of the return signals that represent reflections from the obstacle are identified and analyzed in the time domain to estimate the transmission coefficient of the wall, either by estimating wall parameters or by using a novel shift and add procedure. The estimated transmission coefficient is used to filter the received signals to reduce the components of the received signal that are generated by the obstacle, and to compensate for distortion caused by the obstacle in the portions of the transmitted signal that are reflected by the target and returned, through the obstacle, to the radar system.

Abstract: Embodiments relate to apparatuses, systems and methods for testing high-frequency receivers. In an embodiment, a method includes integrating a pulse train generator and a receiver in an integrated circuit; generating a pulse train by the pulse train generator and applying the pulse train to an input of the receiver; measuring at least one property of the pulse train; and determining at least one characteristic of the receiver using the at least one property of the pulse train. In an embodiment, an integrated circuit includes a receiver, and a pulse train generator configured to generate a pulse train and apply the pulse train to an input of the receiver, wherein at least one characteristic of the receiver can be determined using at least one measured property of the pulse train.

Abstract: Disclosed is a method and a radar apparatus for transmitting a transmission signal through a changing transmission frequency band in order to avoid signal interference, thereby exactly detecting a target object without misrecognition.

Abstract: A machine tool monitoring device of a machine tool for machining a work piece, includes a signal unit (24) provided for an ultra-broad-band operation. The signal unit (24) processes a signal (32, 34), which has a sequence (46) of pulses (48) and includes an arithmetic-logic unit (40) for associating a detected signal (34) with a use situation (52, 58) by means of a fuzzy logic-based and/or neural logic-based signal processing. The signal unit (24) preferably has a programmable data base (44) in which a use situation (52, 58) in a machining process is associated with a procedure (56, 60) for changing the machining process.

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: A multi-band RF transceiver for transmitting communications data and radar signals includes a transmitter having a source of communications data and radar signals. A modulator combines the data and radar signals and then modulates the combined signal with a carrier signal generated by a synthesizer. A processor instructs the synthesizer to change the carrier frequency and the source to provide data and radar signals corresponding to the carrier frequency so that multiple bands are transmitted over a desired spectrum. A receiver includes a demodulator that demodulates the received signal and a synthesizer that generates a signal that tunes the demodulator to the desired carrier frequency. A processor instructs the synthesizer to change the carrier frequency so that the demodulator demodulates the multiple bands of data and the radar signals over the desired spectrum.

Abstract: A system and method of vehicular wireless communication over a Dedicated Short Range Communication service band is provided. The system includes a vehicle having a navigation means, a processor, and a communication means for transmitting a message via a wireless communications link. The system includes a control channel for communication a safety communication and a service channel for communicating a non-safety communication. The control channel is subdivided into a contention-free period having a safety exchange interval of time for transmitting a safety communication and a contention period having a non-safety service interval of time for transmitting a non-safety communication. The system further includes an access point in communication with the vehicle via the communications link within region.

Abstract: A movement detection system includes a microwave antenna able to transmit microwave frequency signals into a space. An electronics controller is connected to the microwave antenna, and is configured to continually measure the impedance of the microwave antenna while it transmits microwave frequency signals into the space. An interpretive device is connected to receive impedance measurements from the electronics controller, and is configured to interpret and report changes in the magnitude and phase angles of individual impedance measurements as the passing of things and their direction through the space.

Abstract: Disclosure is a forward-looking 3D imaging radar, comprising: a transmitting unit which generates RF signals to be radiated for observing object in front of the radar; a transmitting antenna which radiates the RF signal generated by the transmitting unit; a receiving antenna which receives signals radiated from the transmitting antenna and reflected by the object in front of the radar; a receiving unit which mixes the signal received by the receiving antenna and the branched signal from the transmitting unit, and converts the signal to digital signal; and a signal processor which controls the operations of the transmitting unit and receiving unit, sends command to the transmitting unit to generate RF signals, receives the digitally converted signal from the receiving unit and extracts phase information of the object in front of the radar, and generates 3D radar image by producing altitude information based on the principle of interferometer.

Abstract: A beat-product radio imaging method (RIM) system uses a matched continuous wave (CW) transmitter and receiver to electronically image material in between. Signal attenuation measurements are taken from a number of different transmitter and receiver perspectives around the material. The transmitter and receiver each have a crystal oscillator rated at 10-ppm or better frequency uncertainty. The receiver's crystal oscillator is used as a local oscillator to beat down the transmitter's carrier frequency to baseband. The frequency error between the local oscillator and the transmitter carrier frequencies produces a beat product of less than one Hertz in frequency and its magnitude is inversely proportional to the path attenuation between the transmitter and receiver. An extremely low-pass filter is used to remove everything above one Hertz in the detector. The receiver sensitivity is therefore extraordinarily high.

Abstract: Embodiments of the disclosed technology comprise a ground penetrating radio device and methods of use for obtaining greater resolution. This is achieved by measuring the composition/reflection off a homogeneous material (e.g., metal plate), determining coefficients to correct the measured/reflection in order to make the measurements look like an idealized reference signal, and then using these coefficients in a digital filter to correct measurements/a reflection off a heterogeneous material, such as a road surface. In this manner, the composition of the heterogeneous material is determined with greater accuracy.