Abstract: A method and apparatus for generating short electronic pulses using a modified differential trigger that is partly an analogue sinusoidal voltage and partly a selectable, DC voltage. The differential trigger is applied to a differential base band pulse generator having a NAND gate and AND gate. The trigger is applied to both NAND inputs and to one AND input. The NAND output is applied the other AND input. Such a circuit is an OFF state for all input states. However, as the input switches state, the NAND gate delay causes the AND gate to be ON briefly, generating a short pulse. The timing of this pulse can be controlled by varying the constant DC voltage. By using fast switching SiGe CML gates, short pulses with a controllable time off-set can be generated that are suitable for use in automotive radar applications, using only sub-GHz clocks.

Abstract: A method for reducing the interference between a source transmitting pulses and equipments having nominal bandwidths which are outside the nominal bandwidth of the transmitted pulses, but which respond to sideband energy of the pulses. Phase perturbations are applied to the edges of the pulses produced by the source, to thereby tend to null the sideband energy lying in the nominal bandwidth of the equipments occupying the adjacent nominal bandwidths.

Abstract: A conventional waveform generation circuit was required to increase a number of bits or a sampling rate for a D/A converter to enhance a precision of waveform shaping, and had a problem that a cost was increased. Therefore, as a method for enhancing the precision of waveform shaping, a quantization error of an output waveform is made smaller by controlling an output time interval of an output value from a D/A converter so as to make a difference in an output voltage between target waveform and output waveform smaller. As a result, even if the D/A converter has a small number of bits, the waveform can be generated at high precision. Also, this waveform generation method may be applied to modulation control of a radar apparatus, as a result, constituting a small and inexpensive modulation circuit for an oscillator.

Abstract: The invention relates to a method for detecting the passage by a vehicle of a determined point for monitoring on a road, wherein from a remotely situated location a radar beam is transmitted continuously to the point for monitoring, reflections from the transmitted radar beam are received at the remotely situated location, and it is determined from the received reflections that the vehicle is passing the point for monitoring. The radar beam can herein be transmitted at an acute angle to the travel direction of the passing vehicle. The detection can be used to activate a red-light camera, to measure the speed of the vehicle or measure the traffic intensity, without sensors, for instance induction loops, having to be arranged in the road for this purpose.

Abstract: A method for detecting targets and determining their distance by means of an HPRF radar system including a transmitter for transmitting bursts having a preselectable number Z of transmission pulses and a preselectable pulse repetition frequency PRF and a receiver for receiving the echo signals. Successive bursts are transmitted with a preselectable time lag, where the time lag corresponds to a preselectable number E of transmission pulses. A data record of Z+E detected signals is generated, where each detected signal consists of superimposed echo signals from different unique distance ranges, each distance range having a number A of distance lines, each line having Z+E distance cells. A target is detected by calculating a Z+E-point fast Fourier transform for each distance line, and determining when the signal amplitude is greater than a preselectable threshold value.

Abstract: A pulse compression processor 20 compressing a modulated pulse signal correlately received by a receiver, includes a coefficient calculator 30 calculating a set of filtering coefficients for converting sampled output signal values outside a vicinity of main-lobe of a compressed pulse signal into zero as well as for minimizing S/N loss in a peak value of the main-lobe, and a pulse compression filter 40 compressing the modulated pulse signal based on the set of the filtering coefficients calculated by the coefficient calculator.

Abstract: A radar device includes a code generator, a transmission section, a reception section, a delay section, a despreading process section, a correlation value detection section, a target detection section, an estimation section, an acquisition section, and a correction section. The estimation section estimates a reception intensity of a reflection wave from a target located at a first distance on a basis of a detected correlation value. The acquisition section acquires a cross-correlation value between the first distance and a second distance, on a basis of the estimated reception intensity of the reflection wave from the target located at the first distance, a delayed despreading code used to detect a correlation value for the first distance and a delayed despreading code used to detect a correlation value for the second distance. The correction section corrects the correlation value for the second distance on a basis of the cross-correlation value.

Abstract: A bistatic radar has a radar transmitter at a first location on a moving platform having a motion and a radar receiver at a second location, remote from the first location. The transmitter illuminates a target along an indirect path with an encoded radar signal. The target reflects the encoded radar signal to the radar receiver. The transmitter concurrently provides the encoded radar signal to the radar receiver along a direct path. The encoded radar signal is radiated at a start time from a central reference point, and contains the first location, the pulse start time, the central reference point and the motion of the moving platform. Bit synchronization codes are also included. The radar receiver receives the encoded radar signal from the radar transmitter along the direct path during a first time interval, and the same encoded radar signal reflected from the target along the indirect path during a second time interval.

Abstract: A radar has a transmission section, a reception section that receives a reflected wave of the transmission wave, a transmission switch section, a delay section that delays a predetermined timing, a reception switching section, a difference processing section, and a calculation section. The transmission section switches between a first frequency and a second frequency to transmit a transmission wave having one of the frequencies. The transmission switch section switches between turning-on and turning-off of an operation of the transmission section at the predetermined timing. The reception switching section switches between turning-on and turning-off of an operation of the reception section according to the timing delayed. The difference processing section outputs a difference between the transmission wave and the reflected wave. The calculation section calculates a distance on a basis of a delay amount, when a detection waveform has a difference frequency between the first frequency and the second frequency.

Abstract: A method for reducing the interference between a source transmitting pulses and equipments having nominal bandwidths which are outside the nominal bandwidth of the transmitted pulses, but which respond to sideband energy of the pulses. Phase perturbations are applied to the edges of the pulses produced by the source, to thereby tend to null the sideband energy lying in the nominal bandwidth of the equipments occupying the adjacent nominal bandwidths.

Abstract: A satellite positioning system (SATPS) receiver has a mix of standard and enhanced digital channel processors. The standard digital channel processors perform continuous tracking. During a low SNR and/or fast acquisition mode, the enhanced digital channel processor accumulates samples of a SATPS signal that are identically positioned within corresponding PRN code repetition periods, and plays back the stored accumulated values of the samples in an integration period to a correlation section for correlation with a locally generated PRN code.

Abstract: Described herein is a method and apparatus for improving high range resolution of a radar system. The method comprises phase shifting a radar pulse to be transmitted at substantially the radar transmission frequency and phase shifting the received radar pulse at substantially the radar transmission frequency. The phase shifting is implemented using a monolithic microwave integrated circuit (MMIC) (42) driven by a digital circuit (44) to provide a phase profile which is applied to radar pulse (52) produced by a radar pulse generator (54) and which is also applied to a received radar pulse (60). A master clock and synchronizer (72) provides clock signals for an analogue to digital converter (ADC) (68), the generator (54) and the digital circuit (44) so that the MMIC (42) is clocked at a frequency which is directly harmonically related to the ADC (68). This avoids spurious beat frequencies which could interfere with a wanted radar signal.

Abstract: A distance measuring apparatus measure the distance to a target by measuring the time required for an emitted beam of light to go to and return from the target. The light receiving section of the apparatus converts the received light into an electric signal. The clamp/inversion section of the apparatus clamps and inverts the output of the light receiving section. The comparing section of the apparatus compares the output of the light receiving section and the output of the clamp/inversion section. The determining section of the apparatus identifies the time of receiving the light on the basis of the outcome of the operation of the comparing section.

Abstract: A method for active ranging, such as radar, which sequentially transmits pulses of mutually different waveforms. Receive processing is performed concurrently for all the transmitted waveforms during each interpulse interval, to thereby provide range ambiguity resolution together with continuous return signal integration.

Abstract: A transmission wave is transmitted to a target from a transmission section. A receiving section receives a wave reflected from the target as a received wave. A conversion section converts a time difference between the transmission time at which a transmission wave is transmitted and the receiving time at which a received wave is received in to a voltage. The thus-obtained voltage is subjected to analog-to-digital conversion by means of a processing circuit, whereby a distance is computed.

Abstract: A method for randomly phase modulating a radar altimeter is described. The method includes momentarily applying a signal from a random noise source to an amplifier, applying an output of the amplifier to a voltage controlled oscillator (VCO), applying an output of the VCO to a transmitter and mixer of the radar altimeter to modulate transmissions of the radar altimeter and to demodulate reflected radar transmissions received by the radar altimeter and holding the output of the amplifier constant from before a radar altimeter transmission until after reception of the reflected radar signals from that transmission by the radar altimeter. The method further includes repeating the applying steps and the holding step.

Abstract: An apparatus for preparing a RF radar transmit waveform and for decoding RF return waveforms comprising: a RF-lightwave encoder and a decoding preprocessor to phase-encode the RF radar transmit waveform and partially decode the return signal, the encoder including switched optical delay lines for producing desired RF phase shifts, and the decoding preprocessor including a tapped optical delay line and optical delay lines that counteract the delays imposed by the delay lines of the encoder, wherein the RF-lightwave encoder and the decoders allow shorter compressed pulses and larger pulse-compression ratios to be achieved than can be obtained using conventional electronic approaches. Wideband transmit waveforms can be generated due to the use of the switched optical delay lines and, unlike prior art approaches, is not restricted to single-frequency waveforms. The taps can be weighted to accomplish objectives such as reduction of side lobes in the compressed pulse.

Abstract: To achieve a purpose of the present invention, a pulse wave radar device related to the present invention modulates a first transmitting pulse and a second transmitting pulse which are separated from each other by a predetermined lapse of time and transmits a transmitting pulse wave and, if a lapse of time from transmission of the transmitting pulse wave corresponding to the first transmitting pulse to outputting of a pulse by the receiving circuit is equal to a lapse of time from transmission of the transmitting pulse wave corresponding to the second transmitting pulse to outputting of a pulse by the receiving circuit, decides that the pulses are a receiving pulse reflected from a target.

Abstract: A method for measuring distance and relative speed between two points, one of which is stationary. The method employs a radio signal modulating a periodic pulse train sent from stationary point to a movable point and simultaneously being retransmitted back to the stationary point with both the transmission and the retransmission occurring during exactly the same period of time. The number of pulses sent from the stationary point during that period of time is known. The number of pulses received by the stationary point during the transmission period, being less than all of the pulses sent to the movable point is used to determine the distance. The process is repeated after a precise time period of no transmissions and a new distance is between the points is determined. Knowing the change in distance and the precise time period over which the change occurred, permits a determination of relative speed of the two points.

Abstract: The invention relates to a radar device for measuring a relative distance to a target. It is an object of the invention to precisely determine the relative distance to the target in a wide range. The radar device according to the invention generates a second pulse by demodulating a signal arriving from a target as a response to a wave signal modulated with a first pulse. The radar device evaluates, as the relative distance to the target, such two different instances that an absolute value of a deviation of a ratio of two instantaneous values of the second pulse from a reference value as a ratio of two instantaneous values of the first pulse is to be minimum. The respective two instantaneous values are with a predetermined interval therebetween on a time axis.

Abstract: The invention relates to remote distance measurement by means of a transmitted noise modulated probing signal (E), whereby at least one of a distance (Y(t)) and a velocity (V(t)) in relation to a signal transceiver (200) is determined. The probing of signal (E) is generated on basis of at least one first noise signal (x1(t), x2(t)). The transmitted signal (E) is presumed to be reflected to the signal transceiver (200) via at least one signal reflecting object in the form of an information carrying signal (e). This signal thus constitutes a delayed and possibly doppler shifted version of the transmitted signal (E). Moreover, according to the invention, a second noise signal (x2(t)) is added either to the probing signal (E) before it is transmitted or to the information carrying signal (e) before information pertaining to the reflecting object is derived there from.

Abstract: In order to refine a device and a method for registering, detecting, and/or analyzing at least one object, a registration range and/or at a detection gate being displaced at a scanning speed over a measuring range, in such a way that a target-unique velocity measurement is ensured in continuous detection operation with low latency time and resistance to fluctuations, it is provided that, the receive circuit be divided into at least two channels, which are operable separately from one another, in particular using at least one power divider unit connected downstream from the output terminal of the I/Q mixing unit, of which the first channel of the receive circuit is designed for the purpose of displacing the registration range and/or the detection gate at a constant scanning speed over the entire measuring range, and the second channel of the receive circuit is designed for the purpose of displacing the registration range and/or the detection gate at a variable, in particular reducible scanning speed over the m

Abstract: In an automotive radio wave radar, a center frequency of a transmitted wave is shifted at a certain cycle, and position information of an obstacle detected at three or more center frequencies is subjected to decision by majority to determine whether detection results of the obstacle are erroneous with the occurrence of jamming. If any of the detection results is determined to be abnormal, the abnormal result is discarded. An automotive radio wave radar is realized which can correctly perform the obstacle detection even in the event of jamming without causing erroneous obstacle detection or omission of the detection.

Abstract: A satellite positioning system (SATPS) receiver has a mix of standard and enhanced digital channel processors. The standard digital channel processors perform continuous tracking. During a low SNR and/or fast acquisition mode, the enhanced digital channel processor accumulates samples of a SATPS signal that are identically positioned within corresponding PRN code repetition periods, and plays back the stored accumulated values of the samples in an integration period to a correlation section for correlation with a locally generated PRN code.

Abstract: A radar, sonar, lidar or like active detection, tracking system calculates the clutter which would occur with various different transmit waveforms, and selects from among those waveforms that one which, given the current clutter, is expected to minimize variation or variability of the clutter. The calculation is performed by generating a clutter kernel for the current transmitted or other reference waveform, and calculating the clutter which would result with alternate transmit waveform(s). The variability of the various clutter responses is determined, and the transmit waveform exhibiting the least clutter variability is selected for a later transmission.

Abstract: A pulse radar system has a high-frequency source, which supplies a continuous high-frequency signal and is connected on the one side to a transmission-side pulse modulator and on the other side to at least one mixer in at least one receive path. A pulse modulator is connected upstream of the mixer with regard to its connection to a receiving antenna. The mixer evaluates a radar pulse reflected by an object together with the signal of the high-frequency source. This system does not require a ZO switch and is insensitive to interference.

Abstract: A ranging Doppler radar system for identifying, and measuring range, velocity, direction of movement of a vehicle with minimal interference from surrounding environs and with low probability of intercept by the vehicle. The transmitted radar signal is modulated with pseudorandom code which acts as a frequency spreading agent and which allows a radar system to resolve range to targets into discrete “range cells”. Range cells can be grouped to yield a “range segment” which defines a region of roadway, such as a school zone. Traffic can be monitored in all range cells, or only in a predetermined range segment. Maps of traffic flow and vehicle parameters are generated and displayed using radar output parameters. Images representing vehicles violating posted speed limits are identified and highlighted on the traffic flow maps.

Abstract: A synthetic aperture radar system uses RF bandwidth and Doppler beam sharpening principles to develop fine altitude and along-track resolutions. To achieve accurate cross-track position measurements the system and method exploit a combination of modes based on a novel antenna pattern combination. The unique arrangement of the antenna patterns allows the radar to process terrain elevation measurements in three independent modes, namely, time-delay response (TDR), amplitude monopulse (AM) and phase monopulse (PM). The additional modes address the interfering scatter problem and the calibration issues required for practical and cost effective operation. The approach also maximizes the number of terrain measurements made per look, thereby reducing the impact of errors and noise through averaging and “voting” (i.e., the comparison of measurements and discarding of “outliers”).

Abstract: An improved method of estimating target elevation angle for dual squinted beam radar systems is disclosed. The target's elevation angle is estimated by receiving complex I/Q data from two receive radar beams and calculating the complex ratio of the complex I/Q data. The calculated complex ratio is compared to a set of previously determined reference complex ratios in complex lookup tables that have been corelated to known target elevation angles.

Abstract: A radar fill level measurement sensor for measuring the level of material in a container, includes a transmit/receive circuit that transmits an electromagnetic pulse, and detects reflected electromagnetic pulses and provides an intermediate frequency signal indicative of the reflected electromagnetic pulses. A logarithm detector circuit receives the intermediate frequency signal and provides a logarithmic output signal indicative of the logarithm of the intermediate frequency signal. An evaluation unit receives and processes the logarithmic output signal, to determine the fill level of the material within the container, and provides a fill level measurement signal indicative thereof.

Abstract: The invention relates to remote distance measurement by means of a transmitted noise modulated probing signal (E), whereby at least one of a distance (Y(t)) and a velocity (V(t)) in relation to a signal transceiver (200) is determined. The probing of signal (E) is generated on basis of at least one first noise signal (x1(t), x2(t)). The transmitted signal (E) is presumed to be reflected to the signal transceiver (200) via at least one signal reflecting object in the form of an information carrying signal (e). This signal thus constitutes a delayed and possibly doppler shifted version of the transmitted signal (E). Moreover, according to the invention, a second noise signal (x2(t)) is added either to the probing signal (E) before it is transmitted or to the information carrying signal (e) before information pertaining to the reflecting object is derived there from.

Abstract: A method and apparatus for information modulation for impulse radios are presented in both single-tone and pulse stream configurations. The modulation techniques include combinations of amplitude and phase modulation. The modulation techniques include both digital and analog schemes, including baseband on/off keying modulation, wavelet on/off keying modulation, pulse-position modulation, and FM modulation. Techniques for varying the modulation rate are also provided. Additionally, harmonics impulse ratio configurations are presented to take advantage of the modulation techniques.

Abstract: A method for processing pulsed-Doppler radar signals to detect a target includes transmitting radar signals from a radar system according to a predetermined frequency technique including signals having frequency diversity, receiving signals within a frequency band, including a target return signal having a frequency indicative of the velocity of the target, and transforming the target return signal using a Fourier Transform having a variable frequency scale.

Abstract: First-arriving-pulse detector (FAP) circuitry includes a correlator circuitry and a threshold circuitry. The correlator circuitry correlates a received signal with a template signal to provide an output signal. The threshold circuitry provides a first-arriving-pulse signal depending on the relative values of the output signal of the correlator circuitry and a threshold signal.

Abstract: A system and method for detecting a target. The inventive method includes the steps of receiving a complex return signal of an electromagnetic pulse having a real and an imaginary component; extracting from the imaginary component information representative of the phase component of the return signal; and utilizing the phase component to detect the target. Specifically, the phase components are those found from the complex range-Doppler map. More specific embodiments further include the steps of determining a power spectral density of the phase component of the return signal; performing a cross-correlation of power spectral density of the phase component of the return signal between different antenna-subarray (quadrant channels); and averaging the cross-correlated power spectral density of the low frequency components. In an alternative embodiment, the cross-correlation is performed on the phase component of the range-Doppler map directly.

Abstract: An embodiment comprises a unit generating a control pulse signal by delaying a basic signal in generating a transmission pulse, and a unit performing a gate operation on a received signal using the control pulse signal. Another embodiment comprises a unit generating a control pulse signal by delaying a signal generated using a first basic signal, a second signal for phase modulation having a lower frequency than the first signal, and a pseudo-random signal generated at an intermediate frequency between the frequencies of the first and second signals, and a unit performing the gate operation.

Abstract: A radar apparatus provided with a transmitter for periodic transmission of mutually disjunct groups of N radar transmitter pulses and provided with a receiver for the receipt of echo signals of the groups of radar transmitter pulses. The radar apparatus includes a video processor for processing echoes in a listening time observed between two of the mutually disjunct groups of radar transmitter pulses. By choosing a suitable staggering of the pulses in a group, the target range and velocity may be unambiguously determined.

Abstract: A pulse radar device includes a VCO that oscillates a carrier wave that has been modulated in frequency, a switch that modulates the carrier wave generated by the VCO to a pulse wave, a transmission antenna that transmits the pulse wave that has been modulated by the switch as an electromagnetic wave, a reception antenna that receives a reflection wave obtained by reflecting the electromagnetic wave that has been transmitted by the transmission antenna by a target substance, a mixer that demodulates the reception signal that has been received by the reception antenna on the basis of the carrier wave that has been generated by the VCO, and a limiter that limits an amplitude of the demodulation signal which has been demodulated by the mixer.

Abstract: The present invention relates to a diversity receiver and, more particularly, to a differential amplitude detection diversity receiver employing MRC and a method of receiving signals using the same, calculating the distances between the amplitude ratios of signals received at each antenna and each amplitude candidate value and multiplying the distances by the amplitudes of signals currently received at each antenna.

Abstract: A radar system having an arrangement for producing a code, an arrangement for modulating a transmission signal in a transmit branch, using the code, an arrangement for delaying the code, an arrangement for modulating a signal in a receive branch, using the delayed code, and an arrangement for mixing a reference signal with a receiving signal, the modulation of one of the signals being performed by an amplitude modulation (ASK; “amplitude shift keying”) and the modulation of the other signal by a phase modulation (PSK; “phase shift keying”). Furthermore, a radar system is proposed in which blanking of phase transitions is provided. Also described are methods which may advantageously be carried out, using the radar systems described herein.

Abstract: High dynamic range brightness information is acquired by inputting detection current to a high (adjustable) gain resettable integrator whose output V(t) is compared to a Vth threshold by a comparator whose output is counted by a reset counter as V(t)≧Vth. When a desired count is attained, data acquisition ends, the counter is read, and the entire circuit is reset. A TOF data acquisition circuit includes first and second sequences of series-coupled delay units, and a like number of latch units coupled between respective delay units. A phase discriminator compares output from each chain and feedback a signal to one of the chains and to a comparator and can equalize delay through each chain. A control voltage is coupled to the remaining chain to affect through-propagation delay time. The latch units can capture the precise time when V(t)≧Vth. Successive measurement approximation can enhance TOF resolution.

Abstract: Radar systems are used for ascertaining the range to at least one reflecting object present in an observation area and/or for ascertaining the speed of the at least one reflecting object. Such a radar system emits into the observation area successive transmitter pulses having a determined pulse duration, with a determined pulse-repetition frequency as a transmitted signal. The system receives transmitted pulses reflected by the at least one reflecting object of the transmitted signal as a received signal. The disadvantage thereby is, that the method has high signal dynamics, which has an unfavorable effect on the price of the circuit components required for the signal processing. The new method for operating a radar system shall be performable with cost effective means.

Abstract: The present invention relates to a light-wave rangefinder using a pulse method, which can reduce a measurement error, in which a tuned amplifier converts an electric signal of a light receiving unit into a damped oscillation waveform and thereby an arithmetic processing means can calculate a distance from a measuring position to a reflecting object on the basis of the damped oscillation waveform of the tuned amplifier. An optical noise sampling unit samples an optical noise produced in the rangefinder; an optical-noise storage unit stores sampling data of the optical-noise sampling unit; an arithmetic processing means reduces a measurement error caused by an optical noise on the basis of the sampling data of the optical-noise storage unit; and thereby a distance, a measurement error of which is reduced, can be calculated.

Abstract: The present invention provides a pulse radar apparatus which is capable of detecting properly an object and measuring a distance up to the object in a short distance even if a leakage signal is contained in a received signal. The pulse radar apparatus includes: transmission means for transmitting an electric wave; reception means for receiving the reflected electric wave into which the electric wave transmitted by the transmission means has been reflected by an object to output the received signal thereof; waveform leading part extracting means for extracting a plurality of leading parts of the received signal outputted by the reception means; sampling means for sampling the output of the waveform leading part extracting means at predetermined time intervals; and detection/distance measuring means for judging on the basis of the time interval data outputted by the time interval measuring means whether or not an object is present and when an object is present, calculating the distance up to the object.

Abstract: A forward electromagnetic wave is generated in accordance with a succession of pseudo random noise code signals. An echo electromagnetic wave caused by reflection of the forward electromagnetic wave at an object is converted into a received signal. Direct-current and low-frequency components are removed from the received signal to generate a filtering-resultant signal. The filtering-resultant signal is compared with a preset decision reference voltage to generate a binary signal. The binary signal is sampled into received data. Calculation is made as to a correlation between the received data and the pseudo random noise code signal. The distance to the object is computed on the basis of the calculated correlation. The pseudo random noise code signal is repetitively generated to produce a succession of the pseudo random noise code signals during a surplus time covering a stabilization time taken by the received signal to stabilize in direct-current voltage level.

Abstract: A method for calculating a center frequency and a bandwidth for a radar doppler filter is herein described. The center frequency and bandwidth are calculated to provide radar performance over varying terrain and aircraft altitude, pitch, and roll. The method includes receiving an antenna mounting angle, a slant range, and velocity vectors in body coordinates, calculating a range swath doppler velocity, a track and phase swath bandwidth, and a phase swath doppler velocity. The method continues by calculating a range swath center frequency based on the range swath doppler velocity, calculating a phase swath center frequency based on the phase swath doppler velocity, and calculating a level and verify swath bandwidth based upon the track and phase swath bandwidth.

Abstract: A phase processor is disclosed which is configured to receive processed radar return data from a left radar channel, a right radar channel, and an ambiguous radar channel. The phase processor comprises a plurality of phase detectors each with an input and a reference input. The phase detectors are configured to determine a phase difference between radar return data received at the input and radar return data received at the reference input.

Abstract: A method for resolving radar range ambiguities is disclosed, where the radar is modulated with a phase code which comprises a number of chips. The method includes acquiring a radar return within a verify gate, the verify gate being aligned with one chip of the phase code, determining an amplitude of the return, stepping the gate outbound to a next chip of the code, acquiring a return, and determining if the return has an amplitude greater than a threshold based on the original return. The verify gate is repeatedly stepped outbound to determine if a chip can be found which has an amplitude in excess of the threshold or until returns from all chips within the phase code have been acquired. If such a position is found, search logic of the radar is moved outbound to the chip position which had the highest amplitude return, if not the original chip position and the entire process begins again.

Abstract: A sensor front end is disclosed that is able to discriminate objects based on their range from the sensor. The sensor includes an antenna that transmits a sensor signal and, if an object is present receives a reflected signal therefrom. A pulsed oscillator provides a pulsed first signal having a first frequency and phase, and wherein the pulsed oscillator provides the pulsed first signal for a predetermined pulse duration and with a predetermined pulse repetition frequency. The pulsed oscillator provides the pulsed first signal to a first input port of a dual mode mixer that is further coupled to the antenna via a second port. The dual mode mixer transmits a portion of the pulsed first signal from the first input port to the second port and thus to the antenna to be transmitted as the sensor signal. In addition, the dual mode mixer uses a portion of the first signal to mix with the received reflected signal. The dual mode mixer then provides a mixed signal as an output at a third port.

Abstract: A radar system provides unambiguous and uneclipsed range by virtue of pulse-to-pulse frequency diversity, in combination with alternating interpulse intervals and processing which “fills in” target information in the ranges which would otherwise be eclipsed by transmitted pulses.