Abstract: In a radio wave radar system using a two-frequency CW modulation method, it is possible to detect a distance between a host vehicle and a forward vehicle and to realize a stable ACC following travel, even in a condition in which the relative speed is 0. By combining the two-frequency CW modulation method with the frequency pulse CW modulation method, that is, by using combination with the two-frequency CW method when the relative speed occurs and the frequency pulse CW method when the relative speed is close to 0, even if the relative speed is 0, the IF signal obtained from the reflected wave from the forward vehicle can be generated to detect the existence of the ACC target vehicle, so that it is possible to realize a stable ACC following travel.

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: In a device for bistatic radar applications, at least two spaced-apart radar sensors having separate carrier-frequency oscillators are provided, which do not require phase synchronization. The pulse modulation is carried out time-synchronously for all transmitter and receiver pairs. The cross-echo signals can be analyzed in an analyzing unit, in which a mixing of the transmitted and received signals takes place.

Abstract: A method for processing a received, modulated pulse (i.e. waveform) that requires predictive deconvolution to resolve a scatterer from noise and other scatterers includes receiving a return signal; obtaining L+(2M?1)(N?1) samples y of the return signal, where y(l)={tilde over (x)}T(l) s+v(l); applying RMMSE estimation to each successive N samples to obtain initial impulse response estimates [{circumflex over (x)}1{?(M?1)(N?1)}, . . . , {circumflex over (x)}1{?1}, {circumflex over (x)}1 {0}, . . . , {circumflex over (x)}1{L?1}, . . . , {circumflex over (x)}1{L}, {circumflex over (x)}1{?1 +(M?1)(N?1)}]; computing power estimates {circumflex over (?)}1(l)=|{circumflex over (x)}1(l)|? for l=?(M?1)(N?1), . . . , L?1+(M?1)(N?1) and 0<??2; computing MMSE filters according to w(l)=?(l) (C(l)+R)?1s, where ?(l)=E[|x(l)|?] is the power of x(l), for 0<??2, and R=E[v(l) vH(l)] is the noise covariance matrix; applying the MMSE filters to y to obtain [{circumflex over (x)}2{?(M?2)(N?1)}, . . .

Abstract: The present invention provides a method for generating HF signals for determining a distance and/or a speed of an object, having the following steps: generating a pulsed demodulated signal (6?) from a first signal (3) and a second signal (4) in a signal generator (31; 1, 2, M1, 7, 8); with a transmitting device (20), sending the pulsed modulated signal (6?) in the direction of an object (40); with a receiving device (21), receiving a pulsed signal (6?) reflected by the object (40); generating a pulsed demodulated signal (4?) from the received signal (6?) and the first signal (3) in a first signal processor (32; M2, 15); and generating a coherent signal (23) from the pulsed demodulated signal (4?) and the second signal (4) and a noncoherent signal (22) from the pulsed demodulated signal (4?) in a second signal processor (33; M3, 16, 17, 18). The present invention also provides an apparatus for generating HF signals for determining a distance and/or a speed of an object.

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 general purpose system and method for transmitting and coherently detecting UWB waveforms is predicated on the formation of conjugate pair of UWB waveforms. The in-phase and conjugate quadrature waveforms are orthogonal to each other and have the same power spectrum so that when squared and added they sum to the modulation envelope of the waveforms. By defining the waveform pair in this manner, a relatively simple and inexpensive transceiver can be used to transmit and receive the waveforms and yet preserve maximum range resolution and recover all possible energy in the returned waveforms. The transceiver transmits the in-phase UWB waveform and the conjugate quadrature UWB waveform with either a known time delay or orthogonal polarization relation. The time delay may be varied to suppress aliased return signals.

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: A radar transmits electromagnetic energy in pulse repetition intervals and receives reflections from objects in range gates including Doppler filters. The radar approves desirable ambiguous echoes and suppresses ambiguous echoes of no interest or that interfere with the radar's display. The radar frequency varies according to a staggered or wobbling pattern. The ambiguous echoes produce one pulse in the range gates within a predetermined number of periods. The Doppler filter works with an impulse function response that includes a small number of samples. The Doppler filter, during the predetermined number of periods, gives rise to independent samples from reflectors within the radar's unambiguous range. When the independent samples exceed the small number of samples, the radar approves the ambiguous echo. Otherwise, it is suppressed. In this way, ambiguous echoes are prevented from interfering with the reception or display of echoes. The suppression of asynchronous interferences can be made easier.

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: An on-vehicle radar system capable of detecting a range error from range data based on an echo from a target (6). Range error is detected when amplitudes of beat frequency components in two adjacent range gates are substantially equal. The system includes a transmitting unit (1, 2, 4, 5) for radiating a modulated wave having frequency increasing and decreasing repetitively after pulse modulation, a receiving unit (8, 9, 10, 11, 12) for receiving the echo, and an arithmetic unit (13) for detecting a range error ascribable to aberration of modulation band width due to frequency increase and decrease of transmission wave (W1) by comparing a range corresponding to the range gate with that determined from a frequency difference between transmission wave and echo. The arithmetic unit (13) detects the range error on the basis of frequency difference components having substantially same amplitudes in adjacent range gates.

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: Generating an image matrix includes accessing a round-trip time matrix for a space having points. The round-trip time matrix describes an estimated round-trip time for a signal to travel from a transmit antenna, to a point, and to a receive antenna. Signals reflected from an object of the space are received at the receive antennas. The following are repeated for at least a subset of the points to generate an image matrix: select a point of the subset of points; for each receive antenna, establish a waveform of a signal received by a receive antenna and identify a waveform value of the established waveform that corresponds to the selected point according to the round-trip time matrix; and combine the waveform values for the selected point to yield an image value for the selected point. The image matrix is generated from the image values.

Abstract: A system and method are provided for authenticating a new device in a wireless network using an authentication device. First, the new device estimates the distance between the new device and the authenticating device as a first distance measurement, and sends the first distance measurement to the authentication device. The authentication device then estimates the distance between the new device and the authenticating device as a second distance measurement. The authentication device then evaluates the first and second distance measurements to determine if they meet authentication criteria and sends authentication data to the new device only if the first and second distance measurements meet the authentication criteria. These criteria can be that they do not differ by more than a set error value or that they both are below a set maximum value.

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: A security system senses intrusions into a shipping container through the opening of doors, cutting an opening, or removing the doors from their hinges. Intrusion information is transmitted to a remote receiver without interrogation, thereby reducing power consumption. Sensing is accomplished by employing a range-gated micro-impulse radar (“RGR”) that generates microwave pulses that bounce around the interior of the container. The RGR includes a range gate that enables measuring reflected signals during the time gate period that is set for the time it takes a pulse to propagate a maximum distance within the container and reflect back. A direct current signal level is produced that represents the average reflected signal level within the container, and a Doppler shift measurement is made that represents motion inside the container. The signals are conveyed to the transmitter for conveyance to the remote receiver.

Abstract: A pulse wave radar device transmits at a constant period a transmitting signal in which identification data for identifying of pulse wave radar devices is added to a distance-measuring signal so that any other pulse wave radar device can identify a receiving wave reflected by a target owing to a transmitting wave that itself has transmitted.

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: A millimeter wave pulsed radar system includes a radar synthesizer having a voltage controlled oscillator/phase locked loop (VCO/PLL) circuit, direct digital synthesizer (DDS) circuit and quadrature modulator circuit that are operative to generate an intermediate frequency local oscillator signal (IF/LO signal). A radar transceiver is operative with the radar synthesizer for receiving the IF/LO signal. A transmitter section has a frequency multiplier that multiplies the IF/LO signal up to a millimeter wave (MMW) radar signal and a receiver section and includes a direct conversion mixer that receives a MMW radar signal and the IF/LO signal to produce I/Q baseband signals that are later digitized and processed.

Abstract: A method, an arrangement and a radar level gauging system for preventing interference, which radar level gauging system comprises at least two radar level gauges arranged to measure a filling level of a product kept in a container. Microwave pulses are transmitted towards the surface of said product and microwave pulses reflected by said surface are received by said at least two radar level gauges. Information is provided with said microwave pulses and said information is used for controlling the measurement pulses of said at least two radar level gauges.

Abstract: Methods and apparatus are provided for radar systems using multiple pulses that are shorter than the expected range delay extent of the target to be imaged. In one implementation, a method for performing radar includes the steps of: transmitting a plurality of pulses, each pulse having a different center frequency and a time duration shorter than an expected range delay extent of a target, wherein a total bandwidth is defined by a bandwidth occupied by the plurality of pulses; receiving reflections of the plurality of pulses; and performing pulse compression on the received pulse reflections to generate a detection signal having a radar resolution approximately equivalent to the transmission and reception of a single pulse having the total bandwidth. In preferred form, the pulses comprise ultrawideband (UWB) pulses each occupying a sub-band of the overall system bandwidth.

Abstract: A positioning system including a sensor, a drive sequencer and an actuator. The sensor senses the actuator position and provides position signals to drive the sequencer which responsively computes and drives the actuator in open loop moves containing dwell intervals of position. The actuator positions a mirror or other load means to reflect an optical beam as desired. Either preprogrammed or non-repeating sequences of actuator stopping positions can be synchronized with a laser. During dwell times, mirror position accuracy better than 10 microradians is suitable for tuning CO2 pulse burst or CW lasers.

Abstract: A method of controlling a switching element in a switching regulator power supply of a radar. The method of controlling the switching element comprises only switching the switching element during predetermined time intervals, the predetermined time intervals advantageously being sample intervals of a pulse repetition interval of the radar. Thereby by having knowledge of the time intervals the switching element is switching, being able to remove or diminish any influence the switching can have on the quality of received signals and subsequent processing of these signals.

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: In order to create a method for eliminating dummy objects in short-range pulse radar sensors, in which radar pulses are transmitted at a defined frequency, and the time until they are reflected by an object and received again is measured, and besides the transmitted pulse (TX pulse), a delayed second pulse (RX pulse) is generated, which avoids the known disadvantages of the prior art and with which the elimination of dummy objects in short-range pulse radar sensors can be assured, it is provided that the transmitted pulses (TX pulses) and the additionally generated second pulses (RX pulses) delayed relative to them are modulated by a binary phase-shift keying process.

Abstract: A method for processing a received, modulated pulse (i.e. waveform) that requires predictive deconvolution to resolve a scatterer from noise and other scatterers includes receiving a return signal; obtaining L+(2M?1)(N?1) samples y of the return signal, where y(l)={tilde over (x)}T(l)s+v(l); applying RMMSE estimation to each successive N samples to obtain initial impulse response estimates [{circumflex over (x)}1{?(M?1)(N?1)}, . . . , {circumflex over (x)}1{?1}, {circumflex over (x)}1{0}, . . . , {circumflex over (x)}1{L?1}, {circumflex over (x)}1{L}, . . . , {circumflex over (x)}1{L?1+(M?1)(N?1)}]; computing power estimates {circumflex over (?)}1(l)=|{circumflex over (x)}1(l)|2 for l=?(M?1)(N?1), . . . , L?1+(M?1)(N?1); computing MMSE filters according to w(l)=?(l)(C(l)+R)?1s, where ?(l)=|x(l)|2 is the power of x(l), and R=E[v(l)vH(l)] is the noise covariance matrix; applying the MMSE filters to y to obtain [{circumflex over (x)}2{?(M?2)(N?1)}, . . . , {circumflex over (x)}2{?1}, {circumflex over (x)}2{0}, .

Abstract: A synthetic aperture radar (SAR) compensates for ionospheric distortions based upon measurement of the group delay, particularly when operating in the VHF/UHF band. The SAR is based upon a multi-input multi-output (MIMO) technique for estimating the effective ionospheric conditions, which is referred to as the group delay approach. The group delay approach is divided into a 1-dimensional (range) approach and a 2-dimensional (range and cross-range) approach. The group delay measures the effective or observed TEC, which is used to reduce the ionospheric distortion.

Abstract: A synthetic aperture radar (SAR) for a moveable platform includes an antenna, a radar transmitter and radar receiver cooperating with the antenna. A radar processor is connected to the radar transmitter and radar receiver to account for the Faraday rotation introduced by propagation through the ionosphere by estimating an individual ionospheric distortion for each received echo pulse based upon a measured Faraday rotation, and reducing the ionospheric distortion for each received echo pulse based upon the estimated individual ionospheric distortion associated therewith for providing a compensated echo pulse.

Abstract: A method for determining the position of at least one second transmitting and receiving device (3) in respect of a first transmitting and receiving device in a passive access control system operating in the GHz range, comprising the steps of using a radar method, wherein signals (f1, f2) are received in the first transmitting and receiving device on the left-hand side and right-hand side of a modulation frequency (fmod), determining the distance of two signals (f1, f2) closest to the left-hand side and right-hand side modulation frequency (fmod) wherein the distance is proportional to the distance between the first transmitting and receiving device and at least one second transmitting and receiving device (3), so that multipath propagations are not taken into consideration.

Abstract: A radar based sensor detection system comprises a microwave source operative to provide a continuous wave signal at an output. A pulse-former is coupled to the output of the source and is operative to provide at an output a variable length pulse that increases the transmitted energy of the radar system according to the range of object detection. A modulator is coupled to the output of the pulse-former for providing a modulated pulse signal when required. A transmit/receive switch coupled to the output of the modulator is selectively operative between a first transmit position and a second receive position. A transmit channel coupled to the transmit/receive switch transmits the pulse signal when the switch is operated in the transmit position. A receiving channel coupled to the transmit/receive switch receives the modulator signal when the switch is operated in the receive position.

Abstract: A guided wave radar transmitter comprises a probe defining a transmission line including a relatively low impedance target marker above an expected sensing region of the probe. A pulse circuit is connected to the probe for generating pulses on the transmission line and receiving a reflected signal from the transmission line. The reflected signal selectively includes a target pulse representing the target marker and a level pulse representing material along the length of the probe. A controller is operatively connected to the pulse circuit. The controller normally operates at a relatively low gain to determine a level time to the level pulse to determine material level, and periodically operates at a relatively high gain to determine a target time to the target pulse. The target time is used to compensate the level time for properties of vapor above the material level.

Abstract: Radar apparatus and methods of use thereof for imaging and/or spectrometric analysis. The invention employs pulsed radar signals for magnifying, imaging, scale measuring, identifying and/or typecasting the composition of substances by radargrammetric imaging and/or statistical analysis of energy/frequency spectrums. The invention may be used to locate and/or distinguish a substance from other substances, to image a substance/feature and to monitor the movement of an imaged substance/feature. The systems and methods can be adapted for a variety of applications at a wide range of scales and distances, from large scale, long range applications such as geophysical imaging/analysis, to the small scale such as material typecasting applications and small scale (including microscopic) imaging/analysis, including biological and medical imaging and diagnostic applications. The invention includes novel antenna assemblies and novel data processing techniques.

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: Simultaneous improvement in resolution, frequency range, dynamic ranges, as well as signal-to-noise ratio of spectrum analysis is possible by the huge increase in speed and capacity of digital data processing. In coherent pulse sounding (especially in monostatic Radar and Sonar), precise determination of the frequency, amplitude, and phase of wanted signals and unwanted interferers in the frequency domain and their elimination in the time domain data set leads to substantial improvement in the dynamic range of the analysis. Thus, a new apparatus and method of unevenly spaced transmitter pulses becomes feasible to increase the number of samples in a time period limited by the coherency requirements of the data set. The invented apparatus and method overcomes the inherent limitation in dynamic range of the spectral amplitudes due to cross-talk and sparse sampling. Non-linear spectrum analysis can improve signal-to noise further. Pre-cleaning of spread-spectrum data is another application of this method.

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: The present invention provides a method for generating HF signals for determining a distance and/or a speed of an object, having the following steps: generating a pulsed demodulated signal (6′) from a first signal (3) and a second signal (4) in a signal generator (31; 1, 2, M1, 7, 8); with a transmitting device (20), sending the pulsed modulated signal (6′) in the direction of an object (40); with a receiving device (21), receiving a pulsed signal (6″) reflected by the object (40); generating a pulsed demodulated signal (4″) from the received signal (6″) and the first signal (3) in a first signal processor (32; M2, 15); and generating a coherent signal (23) from the pulsed demodulated signal (4″) and the second signal (4) and a noncoherent signal (22) from the pulsed demodulated signal (4″) in a second signal processor (33; M3, 16, 17, 18).

Abstract: A method for transmitting a radar signal comprises the step of transmitting a series of pulses, each of the pulses being separated in time by an interpulse period, and each of the pulses in the series being modulated in accordance with a different character of a first code

Abstract: A double side band diplex linear frequency modulated superimposed radar system determines the range of targets as a function of the amplitude variation of reflected target Doppler signals. The present invention includes a real radar system that accurately determines the range of fading targets and the magnitude of the velocity of the targets. The present invention also includes a complex radar system that determines the relative velocity of targets in addition to the range of targets. The present invention also includes a real radar system having BPSK modulation. The selection of BPSK modulation enables or facilitates. the implementation of a portion of the system in digital form.

Abstract: A method for radar-based gauging of the level of a substance in a tank (13) having at least one interfering structure (16a-c), comprises the steps of: (i) transmitting a microwave signal in a plurality of radiation lobes (15a-b; 15a-d), each of which being individually directed towards the substance and at least one of which being directed towards the interfering structure; (ii) for each of the radiation lobes detecting temporally resolved the microwave signal as reflected against the substance, and for at least one of the lobes detecting the microwave signal as reflected against the interfering structure; (iii) based on signal strengths of the detected microwave signals, distinguishing the detected microwave signals, which have been reflected against the substance; and (iv) based on a propagation time of at least one of the microwave signals distinguished as those, which have been reflected against the substance, calculating the level of the substance.

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: A method and a device for detecting objects that has at least two near distance sensors installed on a vehicle. The at least two near distance sensors have detection ranges that overlap at least partially. The relative positions of possible detected objects with respect to the at least two near distance sensors are determined in the overlap area by the triangulation principle. Possible apparent objects obtained by determining the relative position of possible detected objects are identified using dynamic object monitoring.

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: A pulse radar system capable of mapping multiple targets essentially simultaneously using a single radar antenna. By alternately transmitting radar pulses toward multiple targets positioned at different angles relative to the antenna and alternately receiving return signals from the multiple targets as the radar antenna is switched between multiple beam positions, a time-interleaved radar operation is achieved which enables multiples targets to be mapped, and thus tracked, at the same time. A different radio frequency is preferably employed for each target so as to avoid interference and ambiguous returns. Using the teachings of the present invention, between two and twenty radar maps, and possibly more, can be generated simultaneously in approximately the same amount of time required to map a single target using conventional systems of the prior art.

Abstract: A positioning system including a sensor, a drive sequencer and an actuator. The sensor senses the actuator position and provides position signals to drive the sequencer which responsively computes and drives the actuator in open loop moves containing dwell intervals of position. The actuator positions a mirror or other load means to reflect an optical beam as desired. Either preprogrammed or non-repeating sequences of actuator stopping positions can be synchronized with a laser. During dwell times, mirror position accuracy better than 10 microradians is suitable for tuning CO2 pulse burst or CW lasers.

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: A method and apparatus for the detection of radioactive material in an area is disclosed. The apparatus comprises a transmitter operatively arranged to transmit electromagnetic radiation, a receiver operatively arranged to measure an intensity of the electromagnetic radiation, and processing means operatively arranged to determine the presence of radioactive material based on the intensity measurement. Two receiver configurations are possible. In the first, the receiver measures the intensity of the electromagnetic radiation reflected by ion tracks in the air proximate to the area scanned for radioactive material. Alternatively, the receiver measures the intensity of the electromagnetic radiation transmitted by the air proximate to the area scanned for radioactive material.

Abstract: In a method for the determination of the unambiguous range for the measurement of the IF deviation in a frequency-regulated radar system, a frequency adjustment or tuning of the radar system is carried out during the reception of an echo signal by adjustingly setting respectively at least one value for the IF deviation around the value zero in the unambiguous range of the IF deviation as well as in an ambiguous range of the IF deviation. Then, the unambiguous range is recognized as such by comparison of the signal amplitude and/or the number of the detected targets during these adjustment settings, because the unambiguous range exhibits the highest signal amplitude and/or the greatest number of detected targets (i.e. echo signals).