Abstract: A radar system processes signals in a flexible, adaptive manner to determine range, Doppler (velocity) and angle of objects in an environment. The radar system includes transmitters configured to transmit radio signals, receivers configured to receive radar signals, and a control unit. The received radio signals include transmitted radio signals transmitted by the transmitters and reflected from objects in an environment. The control unit adaptively controls the transmitters and the receivers based on a selected operating mode for the radar system. The selected operating mode meets a desired operational objective defined by current environmental conditions. The control unit is configured to control the receivers to produce and process data according to the selected operating mode.

Abstract: The invention relates to an antenna soft switching system of an Angle of Departure, AoD, direction finding transmitter unit. The soft switching system comprises: a timing unit for obtaining at least a starting time of a switching event, a switching network arranged on a radio frequency, RF, signal path between an RF port and a first antenna port and a second antenna port, and a generator unit for generating at least one waveform for controlling the switching network. The generator unit is configured to control the switching network so that the amplitude of the RF signal is switched substantially smoothly from the first antenna port to the second antenna port so that level of unwanted emissions of a transmitted RF spectrum of the AoD directional finding transmitter unit are reduced. The invention relates also to an AoD direction finding transmitter unit comprising the antenna soft switching system and to an antenna soft switching method for an AoD directional finding transmitter unit.

Abstract: The present invention relates to a signal processing device for accurately detecting a moving object without being influenced by the speed of the moving object. This signal processing device is provided with: at least two cross-correlation calculation units for calculating cross-correlation functions for the waveform of a reflection signal obtained through the reflection, by an object, of a transmission signal having a varying frequency and different correlation waveforms generated from the waveform of the transmission signal; a combination unit for combining the at least two cross-correlation functions from the at least two cross-correlation calculation units so as not to be separated in the frequency shift direction; and a detection unit for detecting the object on the basis of the cross-correlation function resulting from the combination.

Abstract: Methods, systems and non-transitory computer readable mediums for processing radar signals to recover signals inside a blind region are disclosed. A transmission signal is transmitted from a radar system. The radar system receives a return signal. The return signal includes a first portion of the transmission signal leaked during transmission and a second portion reflected from an object within the blind region. The return signal is partially decoded by zeroing out the first portion of the transmission signal to form a modified return signal. Pulse compression is performed over the modified return signal to form a compressed return signal. The compressed return signal is processed to calculate moment products. The moment products are calibrated with a calibration factor, wherein the calibration factor is multiplied against only calculated moment products of range gates which have been partially decoded.

Abstract: A radar system for mobile applications includes transmitters and receivers. The transmitters are configured for installation and use in a mobile application. Each of the transmitters is configured to generate a radio signal. The receivers are configured for installation and use in the mobile application. Each of the receivers is configured to receive radio signals that include transmitted radio signals transmitted by the transmitters and reflected from objects in the environment. A first transmitter of the transmitters is configured to frequency modulate the transmitted radio signal using a shaped frequency pulse which is defined by a sequence of chips. The sequence of chips is selected to realize a selected frequency pulse shape.

Abstract: A system and method using a multi-node radar system involve receiving reflected signals at each node of the multi-node radar system, the reflected signals resulting from reflection of transmitted signals by one or more objects, and generating velocity lines associated with each of the reflected signals received at each of the nodes, each velocity line being derived from a radial velocity Vr and an angle of arrival ? determined from the reflected signal received at the node. The method also includes determining one or more intersection points of the velocity lines, and estimating a velocity of each of the one or more objects based on the one or more intersection points. Each intersection point corresponds with the velocity for one of the one or more objects and the velocity is a relative velocity vector between the one of the one or more objects and the radar system.

Abstract: A range-direction frequency domain converting unit (231-1) converts reception video signals into signals in a range direction frequency. A hit-direction frequency domain converting unit (232-1) converts the signals in the range direction frequency into signals based on the velocity and the range direction frequency so that the target Doppler frequency belongs to the same velocity bin number independently of variations in frequencies of transmission signals. A correlation unit (233-1) generates signals based on the velocity separated for each of the transmission frequencies and a range after correlation. An integration unit (234-1) generates band-synthesized signals based on the velocity and a range after correlation. A candidate target detecting unit (241) detects candidate targets based on the signal intensity from the output signals of the integration unit (233-1).

Abstract: A system and method to detect an object with a radar system involve transmitting two or more sets of linear frequency modulated signals with a gap duration Dg, during which there is no transmission, between each of the two or more sets of the linear frequency modulated signals. Each of the two or more sets of the linear frequency modulated signals defines a sub-frame, and two or more sub-frames defines a frame. The method includes receiving reflections resulting from the linear frequency modulated signals encountering one or more objects in a field of view of the radar system, and processing the reflections to identify the one or more objects. The processing includes performing an on-off Radon transform to correct a phase bias caused by the gap duration during which there is no transmission.

Abstract: The technology described in this document can be embodied in a radar system that employs pulse compression waveforms. In one aspect, a radar system includes a transmitter device and a receiver device, which are both configured to access a storage device. The storage device is configured to store a first sequence of values and a second sequence of values. The first sequence of values can represent phase values for a transmit waveform. The second sequence of values can represent complex values for a filter waveform. The first and second sequences of values are generated via a joint optimization process. An objective function of the first and second sequences is a weighted sum of metrics indicative of a sidelobe level of a simulated range response and frequency suppression of the transmit and filter waveforms outside and portions inside of a target bandwidth.

Abstract: A ranging system includes an input for receiving a wireless signal and a detector for determining an estimate of a time-of-arrival of the wireless signal at the ranging system. The detector includes a first module for processing the wireless signal according to a non-linear, monotonic transformation to generate a modified signal, a second module for compressing the modified signal according to a linear transformation, resulting in a compressed signal including a number of elements, each element corresponding to a different time segment of the modified signal, and a third module for applying a decision function for determining an output including a first element of the number of elements, corresponding to the time-of-arrival of the wireless signal at the ranging system, applying the decision function, including comparing the elements of the compressed signal to corresponding thresholds of a number of thresholds associated with the number of elements.

Abstract: A method (e.g., a method for measuring a separation distance to a target object) includes transmitting an electromagnetic first transmitted signal from a transmitting antenna toward a target object that is a separated from the transmitting antenna by a separation distance. The first transmitted signal includes a first transmit pattern representative of a first sequence of digital bits. The method also includes receiving a first echo of the first transmitted signal that is reflected off the target object, converting the first echo into a first digitized echo signal, and comparing a first receive pattern representative of a second sequence of digital bits to the first digitized echo signal to determine a time of flight of the first transmitted signal and the echo.

Abstract: There is provided methods and device for imaging objects comprising unsupervised classifying and data analyzing of the object to detect and identify the structure of the object and further display the object's structure/underlying structure, for example the arrangement of and relations between the parts or elements of the object by using a location module configured to record the physical location of an antenna array.

Abstract: A wireless communication system, comprising one or several nodes (A) equipped by a wireless radio interface that is adapted for transmitting digital messages modulated in the form of a series of frequency chirps, for example, LoRa-modulated radio signals. The message is received simultaneously by several base stations (C, D, E), and a server (S) is arranged for dividing the frames by the diverse stations and recombining a corrected frame for the intended recipient (B) based on error codes. Advantageously, the base stations being adapt their timing error compensation strategy when the error codes indicate a corruption of the message.

Abstract: Methods and apparatus to determine an accurate distance to a target using reference signal interpolation is disclosed. An example apparatus includes an interpolator to receive a first sample of a reference signal and a second sample of a reference signal; and interpolating a reconstructed reference signal sample based on the first and second samples, the reconstructed reference signal corresponding to the reference signal; a correlator to generate a plurality of phase-shifted, reconstructed reference signals; and correlate each of the plurality of phase-shifted, reconstructed reference signals with a reflected signal; and an optimal phase selector to determine an optimal phase based on the correlations and output a distance to a target based on the optimal phase.

Abstract: Various embodiments are described that relate to a switched-capacitor in a chaotically modulated communication device. For one chaotically modulated communication device to communicate with another chaotically modulated communication device, the devices should be finely tuned with one another. To achieve this fine tuning, the devices can employ a switched-capacitor set that can function as a variable resistor set. Employing the switched-capacitor set can cause achievement of precise resistances that allow the devices to successfully communicate with one another.

Abstract: Example methods and apparatus to detect transport faults in media presentation systems are disclosed. An example method includes identifying, by executing an instruction with a processor, a cause leading to sending of a first transport failure alert associated with a media stream, counting, by executing an instruction with the processor, a number of false alerts associated with the cause, and when the number of false alerts associated with the cause satisfies a first threshold, adjusting, by executing an instruction with the processor, a second threshold used to determine whether to generate a second transport failure alert associated with the cause.

Abstract: It is common practice in modern radar to utilize some type of downconversion to an intermediate frequency or baseband before analog-to-digital conversion takes place. Several microwave components are needed for this downconversion process, including a tunable local oscillator, bandpass filters, amplifiers, and other signal conditioning devices. The present invention eliminates many microwave components in the radar receiver by sampling the received signal directly, without downconversion or mixing. The manipulation of the received signals that was formerly done with microwave hardware is now done in a digital signal processor. In addition to simplifying the receiver hardware, this invention will also lead to better utilization of the frequency band, less interference from adjacent bands, improvements in system reliability and stability, reduction in system operation and maintenance costs, and will facilitate future system modifications and upgrades.

Abstract: A radar system for a vehicle includes a transmitter and a receiver. The transmitter transmits an amplified and frequency modulated radio signal. Each transmitter comprises a frequency generator, a code generator, a modulator, a constant-envelope power amplifier, and an antenna. The frequency generator generates the radio signal with a desired center frequency. The code generator generates a sequence of chips at a selected chiprate. A modulation interval between successive chips is a reciprocal of the chiprate. The modulator frequency modulates the radio signal using shaped frequency pulses. The shaped frequency pulses correspond to a first signal, the frequency of which deviates from the desired center frequency during each of the modulation intervals according to a selected pulse shape. The selected pulse shape is determined by the generated sequence of chips. The constant-envelope power amplifier amplifies the frequency modulated radio signal at a desired transmit power level.

Abstract: The present invention concerns a method of detecting particles which move along a trajectory and which produce or at least influence electromagnetic radiation, an electrical field or a magnetic field, wherein the electromagnetic radiation, the electrical field or the magnetic field is detected, in which a structuring device is used, which either ensures that the particles along the trajectory produce or at least influence electromagnetic radiation, an electrical field or a magnetic field substantially only at non-periodic spatial spacings, or ensures that the electromagnetic radiation, the electrical or the magnetic field is detected substantially only at non-periodic spatial spacings along the trajectory.

Abstract: A method, device, system and use for determining a distance, location and/or orientation including the at least relative determination of a position of at least one object using at least two active anchors. A first signal is emitted by a first of the two anchors and is received at the object and by a second of said two anchors. A phase measurement is performed at said second anchor and wherein a distance determination with respect to said first anchor is performed and/or the distance from said first anchor to said second anchor is known. A second, particularly electromagnetic, signal is emitted from said second anchor, and information on phase measurement and distance between said first and second anchors is made available to a computation unit and at least one phase measurement respectively of said first and second signal is performed at said object and made available to said computation unit.

Abstract: A system of active fiducial markers for pose calculation of head mounted displays is described in which information is exchanged among said markers for the purpose of synchronization. Fiducial patterns are made more easily identifiable by selective duty cycles of sub groups of synchronized emitters and means is described to propagate pose information among markers.

Abstract: Disclosed is an apparatus for processing a radar signal, including: a transmitting unit which irradiates a plurality of baseband signals as a plurality of division band penetration signals to a target object based on a channel frequency; a receiving unit which receives a plurality of reflection signals reflected from the target object to integrate the received reflection signals as an integration band response signal; and a control unit which sets the channel frequency so that at least some bands of adjacent division band penetration signals among the plurality of division band penetration signals are overlapped with each other.

Abstract: A system is provided for monitoring communication in a wireless network. The system comprises a sniffer device comprising a first antenna, and a beamsplitter having a curved shape and configured to reflect a portion of a beam transmitted by a second antenna toward the first antenna while transmitting a remaining portion of the beam toward a target.

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: A robot cleaner system is described including a docking station to form a docking area within a predetermined angle range of a front side thereof, to form docking guide areas which do not overlap each other on the left and right sides of the docking area, and to transmit a docking guide signal such that the docking guide areas are distinguished as a first docking guide area and a second docking guide area according to an arrival distance of the docking guide signal. The robot cleaner system also includes a robot cleaner to move to the docking area along a boundary between the first docking guide area and the second docking guide area when the docking guide signal is sensed and to move along the docking area so as to perform docking when reaching the docking area.

Abstract: In embodiments, a device is illustrated for determining a sample rate difference between a first information signal and a second information signal including an offset determiner for determining for each of a plurality of segments of the first information signal, associated offset values which temporally align the plurality of segments with respect to the second information signal and a calculator for calculating the sample rate difference on the basis of the offset values.

Abstract: Distance between two radio frequency devices is estimated by receiving a plurality of spread spectrum chirp signals frequency offset from one another, and evaluating the received plurality of spread spectrum chirp signals for relative phase shifts between the plurality of spread spectrum chirp signals. A fine propagation time is derived using the phase shifts between the spread spectrum chirp signals. A frequency domain despreading window is shifted to reduce the influence of time-delayed near multipath signals in receiving the plurality of spread spectrum chirp signals.

Abstract: A radar system (100) is described including a transmitting assembly (10), a receiving assembly (20), a control unit (30) and a signal processing unit (40). The transmitting assembly (10) receives an input signal (31) and transmits an incident radar signal (2). The transmitting assembly (10) includes a Rotman lens (12) having a lens cavity (74), a plurality of beam ports (60), a plurality of array ports (62) and a patch antenna assembly (14). The lens cavity (74) has a lens gap (h) between 10 microns to 120 microns, and preferably 40 microns to 60 microns. The patch antenna assembly (14) includes a plurality of antenna arrays (130) operable to receive a plurality of time-delayed, in-phase signals from the Rotman lens (12) and to transmit the incident radar signal (2) towards a target (4). The receiving assembly (20) receives a reflected radar signal (6) and produces an output signal.

Abstract: Disclosed is a radar apparatus supporting short range and long range radar operations, wherein a plurality of short range transmitting chirp signals and a plurality of long range transmitting chirp signals are generated by a predetermined modulation scheme and is transmitted to an object through at least one transmitting array antenna and signals reflected from the object is received through at least one receiving array antenna, and the plurality of long range transmitting chirp signals have transmission power larger than that for the plurality of short range transmitting chirp signals.

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

Abstract: A parameter changer changes the parameter of the complementary code input from a multiplexer. A separator separates the time-multiplexed complementary code of which parameter has been changed into the code sequences at the even numbers of the time slots and the code sequences at the odd numbers of the time slots. A demodulator demodulates the received signals using the parameter-changed complementary code in order to obtain the demodulated signal. An interference identifying unit identifies the interference signal included in the received signals using the demodulated signal from the demodulator.

Abstract: Presented is a method for determining speeds (vr14, vr16) and distances (r14, r16) of objects (14, 16) relative to a radar system (12) of a motor vehicle (10), wherein a coverage area (EB) of the radar system (12) is divided into at least two part-areas (TB1, TB2, TB3), the coverage area (EB) is examined for reflecting objects (14, 16) in successive measuring cycles (MZ1, MZ2; MZi, MZi+1), wherein radar signals received in a measuring cycle (MZ1, MZ2; MZi, MZi+1) are processed separated in accordance with part-areas (TB1, TB2, TB3) and processed signals are assembled to form a total result differentiated in accordance with spatial directions. The method is characterized in that from signals received in a first measuring cycle (MZ1; MZi), hypotheses for the distance (r14, r16) and speed (vr14, vr16) of reflecting objects (14, 16) are formed and the hypotheses are validated in dependence on signals received in at least one further measuring cycle (MZ2; MZi+2).

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

Abstract: A high speed high dynamic range and low power consumption analog correlator for use in a radar sensor. The analog correlator combines various pulse replication schemes with various parallel integrator architectures to improve the detection speed, dynamic range, and power consumption of conventional radar sensors. The analog correlator includes a replica generator, a multiplier, and an integrator module. The replica generator generates a template signal having a plurality of replicated pulse compression radar (PCR) pulses. The multiplier multiplies a received PCR signal with the plurality of replicated PCR pulses. The integrator module is coupled to the multiplier and configured to generate a plurality of analog correlation signals, each of which is based on the multiplying between the received PCR signal and one of the replicated PCR pulses.

Abstract: A synthetic aperture processing system that includes a signal transmission unit for generating and radiating a plurality of chirp waves to an irradiation region from measuring sites, a signal reception unit for receiving a plurality of reflected waves caused by the plurality of chirp waves, a range compression unit for range-compressing each of the reflected waves and generating reception data consisting of sinc functions, a cross-correlation computation unit for, based on a plurality of model data segments, calculating correlation values representing a degree of correlation between each of the model data segments and the reception data, and image output unit for outputting the correlation values calculated by cross-correlation computation unit.

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: 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: Provided are transmitter topology, receiver topology and methods for generating and transmitting a radio signal at a transmitter and detecting and processing a radio signal at a receiver. The radio signals are transmitted across a wireless interface using Ultra Wideband (UWB) pulses. A transmitted reference approach is utilized. The radio signal include pairs of UWB pulses with each pair of pulses separated by a fixed time delay. The two pulses are then combined to provide for improved noise immunity.

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

Abstract: In conventional pulse compression processing, sidelobes from strong return signals may hide correlation peaks associated with weaker return signals. Example embodiments include methods of mitigating this near/far interference by weighting a received return signal or corresponding reference signal based the return signal's time of arrival, then performing pulse compression using the weighted signal to produce a correlation peak that is not hidden by sidelobes from another return. Multi-frequency processing can also be used to reduce the pulse width of the transmitted pulses and received return signals, thereby mitigating near/far interference by decreasing the overlap between signals from nearby targets. Weighting can be combined with multi-frequency pulse transmission and reception to further enhance the fidelity of the processed correlation peak. Weighting and multi-frequency processing also enable higher duty cycles than are possible with conventional pulse compression radars.

Abstract: The present invention is directed to an improved radar system that produces high range resolution while using existing narrow processing bandwidths and sampling rates to achieve a low cost radar product that is particularly useful for moving targets. The present invention uses a small number of closely spaced Linear Frequency Modulated Chirps. In one embodiment typically 2, 3, 4 chirps are used. Each frequency is sampled at a rate commensurate with the narrower bandwidth, corrected for motion, Time Aligned and combined to produce a single wide-band chirp but achieved using the lower sample rate commensurate with the narrower transmitted waveform.

Abstract: Methods and apparatus are provided to facilitate the alignment of an antenna. In one aspect, there is provided a transceiver. The transceiver may include an antenna and a downconverter module coupled to the antenna. The downconverter module may convert a signal received at the antenna to another signal. The downconverter module may measure received signal strength. The transceiver may also include a sequence detector for detecting an error rate of a sequence included in the other signal. The transceiver may also include an output module for providing an output representative the error rate, the received signal strength, and a combination of the error rate and the received signal strength. The provided output may be used to enable alignment of an antenna. Related apparatus, systems, methods, and articles are also described.

Abstract: A method and system for examining subsurface targets utilizing an elevated or airborne platform. A broad spectrum of frequencies is transmitted from the platform and is directed at the various subsurface targets. A plurality of chirp signals would be utilized to transmit the entire frequency range. These signals are reflected from the various subsurface targets and are received by the platform. The received chirp signals are combined in a manner to allow the visualization of the subsurface target.

Abstract: An apparatus and method for protecting against incoming projectiles comprising transmitting two radar waveforms, the first waveform comprising a pulsed continuous wave waveform, and the second waveform comprising a pulsed linear chirp waveform over a bandwidth, and based on returned radar data, causing deployment of a defense mechanism to intercept a detected incoming projectile.

Abstract: In conventional pulse compression processing, sidelobes from strong return signals may hide correlation peaks associated with weaker return signals. Example embodiments include methods of mitigating this near/far interference by weighting a received return signal or corresponding reference signal based the return signal's time of arrival, then performing pulse compression using the weighted signal to produce a correlation peak that is not hidden by sidelobes from another return. Multi-frequency processing can also be used to reduce the pulse width of the transmitted pulses and received return signals, thereby mitigating near/far interference by decreasing the overlap between signals from nearby targets. Weighting can be combined with multi-frequency pulse transmission and reception to further enhance the fidelity of the processed correlation peak. Weighting and multi-frequency processing also enable higher duty cycles than are possible with conventional pulse compression radars.

Abstract: A pulsed compression noise correlation radar uses noise modulation and pulse compression technology to scramble recognizable transmit signal characteristics and reduce transmit energy. The pulsed noise correlation radar advantageously uses pulse compression technology, a pulsed linear frequency modulated noise correlation mixer, and a new and innovative noise fused waveform to automatically correlate the pulsed linear frequency modulated (LFM) noise waveform with the received signal. The pulsed noise correlation radar apparatus and system now make it possible to effectively reduce transmitting power, preserve high band widths through oversampling in the receiver, and achieve multi-channel array frequency diversity. A secure pulsed compression noise correlation radar system and methods for undetected target detection with pulsed noise correlation radar and a pulsed LFM fused noise waveform are also provided.

Abstract: A radar having a high time and high spatial resolution and being capable of performing volume scanning with an inexpensive and simple structure, while enabling reduction is size and weight. A radar (50) is provided with an antenna unit (51) including a radio wave lens antenna device, which has a spherical transmission radio wave lens (2), a spherical reception radio wave lens (3), a primary radiator (4) arranged at a focal point of the radio wave lens (2), and a primary radiator (5) arranged at a focal point of the radio wave lens (3). The primary radiators (4, 5) pivot in an elevation direction about an axis connecting center points of the radio wave lenses (2, 3) and pivot in an azimuthal direction about an axis orthogonal to the axis connecting the center points of the radio wave lenses (2, 3).

Abstract: A receiver in an impulse wireless communication. The receiver (300) includes a pulse-pair correlator (304) that receives a signal (316) and divides it into two signals for paths. One of the signals is input to signal multiplier (312) while another signal is delayed by a delay unit (310). The signal multiplier (312) multiplies the received signal (316) by a delayed signal (318). An integrator (314) integrates an output signal (322) over a designated period of time. An adding module (306) sums an output signal (324) from the integrator (314). An acquiring module (308) compares an summing-up output (326) from the adding module (306) with a predetermined threshold value to detect the existence of a transmitting-standard preamble.

Abstract: Narrow virtual transmit pulses are synthesized by differencing long-duration, staggered pulse repetition interval (PRI) transmit pulses. PRI is staggered at an intermediate frequency IF. Echoes from virtual pulses form IF-modulated interference patterns with a reference wave. Samples of interference patterns are IF-filtered to produce high spatial resolution holographic data. PRI stagger can be very small, e.g., 1-ns, to produce a 1-ns virtual pulse from very long, staggered transmit pulses. Occupied Bandwidth (OBW) can be less than 10 MHz due to long RF pulses needed for holography, while spatial resolution can be very high, corresponding to ultra-wideband (UWB) operation, due to short virtual pulses. X-Y antenna scanning can produce range-gated surface holograms from quadrature data. Multiple range gates can produce stacked-in-range holograms. Motion and vibration can be detected by changes in interference patterns within a range-gated zone.

Abstract: An active YIG oscillator driving device is comprised of: an YIG oscillator including a main coil, an FM coil, a frequency generator operating to generate an output frequency in response to a magnetic field generated from the FM coil; a phase locker setting the output frequency to a target frequency by controlling an amount of current provided into the FM coil and adjusting the output frequency; and a main coil controller regulating the amount of current provided into the main coil, if the output frequency varies out of a controllable range by the FM coil, and adjusting the output frequency. A time for setting the output frequency of the YIG oscillator is shortened to improve the stability of the output frequency thereof against environmental conditions.