Abstract: A vehicle includes a plurality of transmitters of a code division multiple access (CDMA) radar system to simultaneously transmit a frame of transmit signals. A first time duration between transmissions of a first pair of sequential ones of the transmit signals is linearly increased to a second time duration between transmissions of a second pair of sequential ones of the transmit signals. The vehicle also includes a receiver of the CDMA radar system to receive reflected energy resulting from reflection of one of more of the transmit signals of one or more of the plurality of transmitters by an object. A controller processes the reflected energy to obtain information about the object and to control an operation of the vehicle based on the information.

Abstract: A radar apparatus includes a plurality of transmit antennas that transmits a plurality of transmission signals using a multiplexing transmission, and a transmission circuit that applies phase rotation amounts corresponding to combinations of Doppler shift amounts and code sequences to the plurality of transmission signals. Each of the plurality of transmission signals is assigned a different combination among the combinations. The combinations include at least one combination of different numbers of multiplexing by the code sequences.

Abstract: The invention relates to a locating method for localizing at least one object using wave-based signals, wherein a wave field emanates from the object to be localized and the wave field emanating from the object is received by a number N of receivers, at least one measurement signal is formed in every receiver, said measurement signal being dependent on the spatial and temporal distribution of the wave field and the phase progression of said measurement signal being characteristically influenced by the signal propagation time from the object to the receiver, wherein, for position locating, phase values for each of the at least two measurement signals are taken as measured phase values, and wherein the current position (P(k)) of the object to be located at the time k is determined by a comparison of at least one linear combination of the measured phase values with at least one linear combination of the associated hypothetical phase values, which result from the transmitter-receiver distance(s), and using a recu

Abstract: A radar system that can block false echoes includes: a local oscillator configured to generate a chirp signal comprising a plurality of chirps, each having a corresponding envelope; a transmitter configured to transmit a signal corresponding to the chirp signal; and a modulation circuit configured to modulate the transmitted signal by regulating a magnitude of one or more portions of the chirp envelopes in a predetermined pattern such that the radar system can discern false echoes which do not match the pattern.

Abstract: A radar device capable of detecting a location of an object using a phased-array antenna capable of receiving a reflected wave from all directions includes one or more linear array antennae and a controller capable of transmitting of a wave T from one or more linear array antennae, and receiving a reflected wave R at the one or more linear array antennae. At least one linear array antennae is the same and/or is different from a linear array antenna that transmits the transmitting wave T, and the reflected wave R being generated by the transmitting wave T illuminating the object. A location of the object is estimated using time from transmission of transmitting wave T to reception of reflected wave R, and a direction of the transmitting wave and/or using a frequency of the transmitting wave and a frequency of the reflected wave, and the direction of the transmitting wave.

Abstract: According to one embodiment, a radar apparatus includes a signal processing device that has a first circuit, a second circuit and a transmitter. The first circuit is configured to determine whether or not there is a radio interference based on a radio signal received via an antenna. The second circuit is configured to, when the first circuit determines that there is the radio interference, select a predetermined pulse pattern based on an avoiding function of a wireless communication device having the avoiding function of the radio interference, the predetermined pulse pattern being separately defined from a pulse pattern of transmission processing for operating a radar. The transmitter is configured to transmit from the antenna a radio signal matching the pulse pattern selected by the second circuit.

Abstract: A direct radiation wireless digital communication system based on a digital programmable metamaterial, including a transmitting system and a receiving system, where information transmitted by the transmitting system is loaded to a programmable metamaterial, and is directly radiated into free space in a form of an ever-changing far-field pattern under the illumination of a feeding antenna; the receiving system collects electric field values received by receiving antennas located at different positions of a far-field region to obtain a far-field pattern, and recovers the transmitted original information according to a mapping relationship between the far-field pattern and a coding sequence. The system does not require a digital-to-analog conversion module and a frequency mixing module.

Abstract: Method and apparatus is a handheld ground penetrating radar which transmits radar pulses and acquires and processes received data for presentation on a display allowing a user to identify buried targets. Novel low cost approach to portable high-resolution light weight penetrating imaging. Method and apparatus for a portable penetrating radar incorporating a display depicting permittivity variation versus distance and time as the medium is scanned.

Abstract: A plurality of repeater devices, each of which may enable forwarding extreme high frequency (EHF) communication between EHF-enabled wireless devices, may form a repeater mesh network. Some or all of the plurality of repeater devices may utilize non-extremely high frequency (non-EHF) control connection in communicating with other repeater devices in the repeater mesh network. The non-EHF control connections may be utilized in establishing, configuring, and/or managing the repeater mesh network. The non-EHF control connections may be also be utilized to enable sending, requesting, and/or receiving periodic and/or dynamic control information. The non-EHF control connections may also be utilized while forming, and/or managing forwarding routes of EHF communication via the repeater mesh network, to enable negotiating and/or setting different isolation techniques among the repeater devices, such as polarization isolation, spatial isolation, and/or use of different frequencies.

Abstract: A vehicle-mounted radar apparatus includes transmission antenna members and a transmitting section provided with an oscillator and phase shifters, a controller, a reception antenna member, and a receiving section. The transmission antenna members transmit radar waves. The oscillator generates radio waves necessary to transmit the radar waves. Each phase shifters changes a phase of the radio waves generated at the oscillator and supplies the phase-shifted radio waves to a corresponding one of the transmission antenna members. The controller controls the phase shifter. The reception antenna member receives reflected waves of the of the radar waves. The receiving section generates a reception signal including the reflected waves that are received through the reception antenna member.

Abstract: A method for determining an undesired condition in an electrical drive system including an electrical machine and an electrical drive, wherein the method includes a) obtaining a measured signal of an electrical or mechanical parameter, b) obtaining a frequency spectrum of the measured signal, that contains a measured frequency component, c) determining whether the measured frequency component is within a predetermined distance from a trend line, which trend line is associated with only one specific frequency component of the electrical or mechanical parameter present during a specific undesired condition, d) on the condition that the measured frequency component is within the predetermined distance from the trend line increasing a counter associated with the trend line, e) repeating steps a) to d), wherein in case the counter reaches a predetermined number determining that the electrical drive system is subjected to the undesired condition associated with the trend line.

Abstract: A radar device that transmits a high frequency signal and detects an object by a reflected wave that is reflected by the object includes a transmitting antenna that transmits the high frequency signal, a receiving antenna that receives a reflected wave that is transmitted by the transmitting antenna and reflected by the object, and a dummy antenna that attenuates a reflected wave that is reflected by a structure arranged on a transmission path of the high frequency signal. The dummy antenna is configured be selectable as an antenna having another function.

Abstract: A power-supply device for supplying electrical power to a radar device that transmits and receives a continuous wave and detects an object reflecting the continuous wave on the basis of a spectrum of a beat signal of the transmitted and reflected waves. The power-supply device includes a power supply section that generates electrical power in a predefined voltage range through a switching section being turned on and off in response to a switching signal, and a switching signal output section that, outputs the switching signal whose frequency is set within one of assignable bands. This leads to a radar system comprised of the radar device and the power-supply device, capable of securely preventing erroneous detection of a frequency peak of the switching signal as a frequency peak of the object.

Abstract: A transmitter device arranged to encode a set of digital input data into a succession of modulated chirps, whereby said digital input data are encoded according to a Gray code into codewords (320, 321, 322) having a plurality of bits, and having an interleaver that distributes the bits (C00, . . . Cnn) of each codeword into a series of digital modulation values (S0, . . . S7), at different bit positions, and to synthesize a series of modulated chirps whose cyclical shifts are determined by the modulation values. A special frame structure is defined in order to ensure high robustness, and variable bit-rate flexibility.

Abstract: An apparatus and method for reducing FM audio artifacts in a receiver are provided. A direct conversion radio frequency (RF) receiver converts an analog FM signal into a phase shifted digital low IF signal. A digital controller coupled to the analog FM receiver provides adaptive frequency translation for different channel spacing and provides adaptive low IF configuration through the different channel spacing, thereby suppressing audio artifacts.

Abstract: Systems and methods for allowing dual-mode radar operation. An exemplary transmission system includes a hybrid coupler that receives a signal produced by a synthesizer and couples the received signal to two output ports. A pulse transmitter receives a pulse transmit-activate signal from a controller, receives an input signal from the hybrid coupler and, if the activate signal has been received, amplifies the received signal based on a predefined desired pulse output transmission setting. A frequency-modulation continuous-wave (FMCW) transmitter receives an FMCW transmit-activate signal from the controller, receives an input signal from the hybrid coupler and, if the activate signal has been received, amplifies the received input signal based on a predefined desired FMCW output transmission setting. An isolator protects the pulse transmitter during FMCW operation and also the FMCW transmitter from receiving power reflected off of pulse transmitter components.

Abstract: Systems and methods are described for computing device motion direction and orientation.

Abstract: The present invention relates to a method for separating transmitted signals in radar systems and an associated radar system. In the method, the signals for transmission are shared among multiple subcarriers by means of OFDM, which subcarriers are assigned to the transmitting antennas according to a distribution scheme. In this distribution scheme, each subcarrier is assigned to one transmitting antennas only. The subcarriers assigned to a given transmitting antenna are spread over the entire signal bandwidth. In this way, very high dynamics may be achieved while retaining complete orthogonality of the signal paths.

Abstract: A non-linear radar is disclosed that is able to detect non-linear target responses that are below the harmonic-noise floor of the radar. To accomplish this below-the-noise-floor sensitivity feature the proposal specifically addresses all of the problems commonly faced by non-linear radar such as linearity of the transmitter path, receiver path, and size, weight, and power, and cost (SWaP-C). The radar operates in both standard and nonlinear modes with signal processing that allows display of nonlinear alone, linear alone, or both types of backscatter. Different combinations of six methodologies allow customization to fit different application needs, from low-cost modest performance, to higher cost and extremely high performance.

Abstract: To provide a microwave/milliwave band high-frequency pulse signal generating device that enables realization of structural simplification, high performance, compact integration, easy design, low power consumption, and low cost.

Abstract: An iterative method for modifying an initial time signal to form a created signal having a prescribed envelope, and frequency notches at prescribed frequency values, wherein the created signal closely resembles the initial time signal, the envelope of the created time signal is the prescribed envelope, and the Fourier magnitude of the created time signal at the prescribed frequency values is nearly zero. The created time signal may be a real-valued signal as well as a complex-valued time signal which closely resembles an arbitrary initial time signal, including initial time signals which are standard transmit signals for radar systems, and which have Fourier transform magnitudes with notches and stop-bands at prescribed frequency values. These notches and stop bands are created by enforcing nulls of prescribed order at the prescribed frequency values within the modified time signal.

Abstract: A high frequency surface wave radar (HFSWR) system with improved performance. Two or more transmitters including separate transmitting antennas (120, 122, 410) are used to improve the performance of the HFSWR over the performance of a comparable system with a single transmitter. In one embodiment, two transmitters are used, and configured to transmit pulses alternately, with a time interval of at least a round-trip travel time corresponding to a maximum target range between any pair of transmitted pulses. A physical receiving antenna array (130) includes a plurality of receiving antenna elements (135), and is connected to receiver circuitry configured to distinguish returns corresponding to pulses emitted by the different transmitters. The returns are concatenated in the receiver circuitry to achieve improved resolution.

Abstract: Provided are a method and apparatus (receiver) of receiving and processing a radio signal in a transmitter-receiver environment. 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 dual mode ground penetrating radar includes an enclosure which houses radar electronics. The dual mode ground penetrating radar includes a enclosure housing radar electronics. The dual mode ground penetrating radar further includes a first antenna feed having ferrite loading and extending outside of the enclosure. The dual mode ground penetrating radar further includes a second antenna feed spaced apart from the first antenna feed, the second antenna feed having ferrite loading and extending outside of the enclosure. An RF signal is provided in at least one of the first and second antenna feeds by the radar electronics.

Abstract: Present novel and non-trivial optical, laser-based measuring systems and method are disclosed. An optical, laser-based, or LIDAR measuring apparatus is comprised of a radiation receiver/transmitter, a beam-forming optical element, a beam steering device comprised of a deviation optical element and at least one actuator used to steer the deviation optical element in response to drive signal(s) from a processor.

Abstract: A ring-shaped first ring-shaped magnetic core, a first excitation coil wound on the first ring-shaped magnetic core, two detection coils wound on the first ring-shaped magnetic core in such a manner that respective input axes of the detection coils are orthogonal to each other, two signal detection/feedback units that detect outputs of the detection coils and feed output signals back to the detection coils, and a first excitation circuit that supplies an excitation current to the first excitation coil are provided, a second ring-shaped magnetic core, a compensation coil wound on the second ring-shaped magnetic core, and a compensation signal generation unit that generates, from an output of a detection coil, a compensation current to be applied to the compensation coil, are further provided, and the second ring-shaped magnetic core and the compensation coil are disposed in positions and directions so that a compensation magnetic field created by the compensation coil cancels interference between magnetic fiel

Abstract: Described are radar systems and methods. A transmit pulse is generated by the radar system. A first portion of the transmit pulse is processed by the radar system to form transmit pulse data. A second portion of the transmit pulse is directed by the radar system into a monitored volume. A return signal is received by the radar system, the return signal at least partially comprising a portion of the second portion of the transmit pulse reflected by one or more objects in the monitored volume. The return signal is processed, by the radar system, to form return signal data.

Abstract: The present invention relates to a method for separating transmitted signals in radar systems and an associated radar system. In the method, the signals for transmission are shared among multiple subcarriers by means of OFDM, which subcarriers are assigned to the transmitting antennas according to a distribution scheme. In this distribution scheme, each subcarrier is assigned to one transmitting antennas only. The subcarriers assigned to a given transmitting antenna are spread over the entire signal bandwidth. In this way, very high dynamics may be achieved while retaining complete orthogonality of the signal paths.

Abstract: A target object detection apparatus is provided. The apparatus includes a transmitter, a receiver, a threshold determiner, a parameter setter, a parameter selector, and a timing controller. The transmitter repeatedly transmits a transmission pulse at a transmission timing. The receiver receives a reception signal at a reception timing set based on the transmission timing. The threshold determiner determines whether an amplitude value of the reception signal exceeds a predetermined threshold at every sampling point and counts the number of sampling points at which the amplitude value of the reception signal exceeds the threshold. The parameter setter sets a plurality of different parameters for controlling the transmission timing. The parameter selector selects the parameter from the parameter settings, to minimize the number of sampling points counted by the threshold determiner. The timing controller controls the transmission timing, based on the parameter selected by the parameter selector.

Abstract: A method for transmission and detection in an adaptive-on-transmit (AT) system operating in the electromagnetic spectrum comprising determining a waveform-filter pair; and employing the waveform-filter pair in transmission and detection, wherein two or more are provided of the group consisting of an auto-correlation function sidelobe level reduction proportional to a the filter length, K, or better, an out-of-band spectral suppression of at least about 40 dB, and a frequency spectrum power tail power decay of K?4 or better.

Abstract: A new approach to radar imaging is described herein, in which radar pulses are transmitted with an uneven sampling scheme and subsequently processed with novel algorithms to produce images of equivalent resolution and quality as standard images produced using standard synthetic aperture radar (SAR) waveforms and processing techniques. The radar data collected with these waveforms can be used to create many other useful products such as moving target indication (MTI) and high resolution terrain information (HRTI). The waveform and the correction algorithms described herein allow the algorithms of these other radar products to take advantage of the quality Doppler resolution.

Abstract: The invention includes a method for transmitting and detecting high speed Ultra Wideband pulses across a wireless interface. The transmitter includes a serializer and pulse generator. The receiver comprises a fixed delay line, multiplier, local serializer (with a sequence matching the transmitter), digital delay lines, low noise amplifier and logic fan-out buffer along with an array of D flip-flop pairs. Each flip-flop pair is enabled, at fixed time increments, to detect signals at a precise time; the timing is controlled by the pseudo-random sequence generated by the local serializer. A local tunable oscillator is controlled by detecting the phase change of the incoming signal and applying compensation to maintain the phase alignment and clock synchronization of the receiver to the clock reference of the transmitter. The invention uses a pair of pulses with a fixed delay and then relies on mixing the two to provide better noise immunity.

Abstract: Provided is a pulse radar device which can attenuate an interference signal and significantly amplify a reflected wave without saturating the interference signal. A baseband amplifier unit (5) is installed in a pulse radar device (1) which is configured to transmit from antenna (3) a transmission pulse wave obtained by modulating a transmission control signal, and to be afterwards switched to a standby mode for a reflected wave obtained by reflecting the transmission pulse wave by an object to be detected.

Abstract: Circuits and methods for generating a pulse are provided. The generating can comprise receiving at least one trigger input signal with a pulse generating circuit; generating a voltage pulse having a duration less than the avalanche time of a transistor in response to at least a portion of the at least one trigger input signal with the pulse generating circuit; transmitting the voltage pulse from the pulse generating circuit to a terminal of the transistor, the transistor constructed and arranged to be operable in an avalanche mode; and outputting an avalanche pulse from at least one terminal of the transistor in response to the voltage pulse. In some embodiments, the pulse can be transmitted with an antenna in a radar system, and a return pulse can be received and processed.

Abstract: A first sector radar generates signals which are obtained by modulating a first code sequence at a first transmission cycle, obtained by modulating a second code sequence at a second transmission cycle, obtained by modulating the first code sequence at a third transmission cycle, and obtained by modulating the second code sequence at a fourth transmission cycle respectively. A second sector radar generates signals which are obtained by modulating the second code sequence at the first transmission cycle, obtained by modulating, at the second transmission cycle, a third code sequence having the opposite polarity to the first code sequence, obtained by modulating, at the third transmission cycle, a fourth code sequence having the opposite polarity to the second code sequence, and obtained by modulating the first code sequence at the fourth transmission cycle respectively.

Abstract: A new approach to radar imaging is described herein, in which radar pulses are transmitted with an uneven sampling scheme and subsequently processed with novel algorithms to produce images of equivalent resolution and quality as standard images produced using standard synthetic aperture radar (SAR) waveforms and processing techniques. The radar data collected with these waveforms can be used to create many other useful products such as moving target indication (MTI) and high resolution terrain information (HRTI). The waveform and the correction algorithms described herein allow the algorithms of these other radar products to take advantage of the quality Doppler resolution.

Abstract: A radar apparatus transmits a high-frequency transmission signal, and receives a signal of a reflective wave reflected by a target. Given a first code sequence of a first code length, a second code sequence of a second code length which is longer than the first code sequence, and a third code sequence obtained by inverting each code of the first code sequence, a first transmission signal obtained by modulating the first code sequence, a second transmission signal obtained by modulating the second code sequence, a third transmission signal obtained by modulating the third code sequence and a fourth transmission signal obtained by modulating the second code sequence are generated in a first transmission period, a second transmission period, a third transmission period and a fourth transmission period respectively.

Abstract: An iterative method for modifying an initial time signal to form a created signal having a prescribed envelope, and frequency notches at prescribed frequency values, wherein the created signal closely resembles the initial time signal, the envelope of the created time signal is the prescribed envelope, and the Fourier magnitude of the created time signal at the prescribed frequency values is nearly zero. The created time signal may be a real-valued signal as well as a complex-valued time signal which closely resembles an arbitrary initial time signal, including initial time signals which are standard transmit signals for radar systems, and which have Fourier transform magnitudes with notches and stop-bands at prescribed frequency values. These notches and stop bands are created by enforcing nulls of prescribed order at the prescribed frequency values within the modified time signal.

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

Abstract: A radar apparatus transmits a radio frequency transmission signal from a transmitter antenna in a given transmission period, and receives a signal of a reflected wave reflected by a target via a receiver antenna. The radar apparatus includes a transmission signal generator that generates a first transmission signal obtained by modifying a code having a third sub-code sequence and a fourth sub-code sequence coupled to each other in a first transmission period, and generates a second transmission period obtained by modifying a code having a fifth sub-code sequence and a sixth sub-code sequence coupled to each other in a second transmission period, and a transmitter RF unit that converts the first and second transmission signals into radio frequency transmission signals, and transmits the radio frequency transmission signals from the transmitter antenna.

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: According to one embodiment, a system for generating a signal includes a monocycle generator, one or more temporal modulators, and a pulse shaper. The monocycle generator generates monocycles that form a signal comprising pulses, where a pulse corresponds to one or more monocycles. The temporal modulators provide instructions the monocycle generator to create a specific spectral response in the signal. A pulse shaper individually modulates at least one monocycle of the monocycles corresponding to a pulse to shape the pulse.

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: Probe data is analyzed to derive Longitudinal Speed Profiles (LSPs) and an Optimal Longitudinal Speed Profile (18) for each road segment or link in a digital map network. The Longitudinal Speed Profiles (LSPs) profiles are calculated during defined time spans whereas the Optimal Longitudinal Speed Profile (18) is based on the LSP for the time span corresponding only to free flow traffic conditions. All of the LSPs can used to create a respective energy cost for each time span, or only the OLSP (18) can be used (or alternatively the RRDSL 16 or LRRDSL 17) to calculate an energy cost for the free flow conditions only. The energy cost can be used to predict the energy required by a vehicle to traverse the link. Navigation software can use the energy cost to plan the most energy efficient route between two locations in the digital map. Sensory signals can be activated if a driver strays from the Optimal Longitudinal Speed Profile (18) to achieve extremely high levels of energy efficiency.

Abstract: A plurality of mini radars that make the radar system conformable to a structure that it is attached or built into. A radar system includes a clock, a plurality of frequency modulated/continuous wave (FM/CW) radar units in signal communication with the clock and a processor in signal communication with the plurality of FM/CW radar units. Each of the plurality of FM/CW radar units includes a row of antenna elements.

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

Abstract: A transmitter apparatus generates a RF pulse signal having alternating high-amplitude pulse-on intervals and low-amplitude pulse-off intervals, and supplies the RF pulse signal as respective individual transmission signals of antenna elements of an array antenna, with the individual transmission signals having a phase distribution during each pulse-on interval whereby a beam is transmitted from the antenna in a predetermined transmission direction. During each pulse-off interval, a different phase distribution is established for the individual transmission signals, thereby reducing the level of noise radiated in the transmission direction during each pulse-off interval.

Abstract: This disclosure provides a target object detection device for detecting different areas by different pulse-shaped signals detecting an area from an antenna position to a given distance. The device includes a transmission module for transmitting different pulse-shaped transmission signals at predetermined timings, a reception module for receiving their reflection signals to generate a reception signal, a saturation detection module for comparing a level of each of the reception signals with a predetermined threshold to detect saturation of the reception signal, and an image forming module for forming a detection image based on the reception signals. The transmission module generates an alternative pulse-shaped signal that is different from the transmitted pulse-shaped transmission signal when the saturation detection module detects the saturation of the reception signal.

Abstract: To provide a smaller radar system having a simple structure with as small number of component parts as possible at a lower cost as compared to conventional ones. A radar system 1 including a 3 dB coupler 5 having four terminals, and a pulse generator 8. A first terminal 51 of the 3 dB coupler 5 is supplied with an output signal from a high frequency oscillator 2 while a second terminal 52 of the 3 dB coupler 5 is connected to a transmitting and receiving antenna 4. Third and fourth terminals 53 and 54 of the 3 dB coupler 5 are connected to two-state devices 6, 7, respectively, which are in impedance mismatched only for a predetermined period of time to totally reflect the signal from the 3 dB coupler 5 and are in impedance matched during the time period other than the predetermined time to direct a signal from the 3 dB coupler 5 to a subsequent electronic circuit.

Abstract: An embodiment of the invention includes a step of transmitting an OFDM waveform including several frequency carrier signals transmitted simultaneously, the frequency carrier signals being coded in order to improve the Doppler response. An embodiment of the invention includes a step of receiving the echoed waveform from the target. The initial phase of each frequency carrier signal is recovered from the echoed waveform. The recovered initial phase of each frequency carrier signal is cyclically shifted in order to compensate for the Doppler effect and subsequently decoded. A compressed pulse is synthesized from the decoded initial phases.