Abstract: A radar signal processing method and system for detecting target objects of unknown acceleration and having low SNRs which reduces the computational burdens and provides a more efficient way of performing the operation of non-coherent integration. Radar signal processing is conducted according to a predetermined scheme in which partially processed received signal data is selectively stored and reused, reducing redundant processing. The radar system receives return signals frequency shifted from a predetermined frequency scheme by unknown amounts. The received signals are coherently integrated transforming them into frequency domain templates which are non-coherently arranged into an array matrix. The data of the frequency domain templates are processed to form presums which are stored for use in forming higher level presums and for forming acceleration bins. Once the acceleration bins have been formed, they are analyzed to detect the presence of target object return signals.

Abstract: A motion detector based on the Doppler principle contains a microwave module for emitting a microwave signal containing at least two frequencies into a room under surveillance and for receiving the radiation reflected from the latter. An evaluation stage is connected to the microwave module and generates first and second Doppler signals from the received radiation. The first and second Doppler signals have a phase difference which is proportional to the distance of an object reflecting the microwave signal. The phase difference is determined by an integral transformation. In addition, the relative size of an object and the direction of travel of an object reflecting the microwave signal can be determined by the evaluation stage.

Abstract: Dual path detection processing in which a low SNR signal processor detects signals over a limited range of low acceleration values and a high SNR signal processor detects signals over a wider range of acceleration values. The low SNR signal processor uses acceleration bins formed from a noncoherent FFT array to detect low SNR signals of far away objects which tend to have lower angular acceleration. Because close proximity target objects tend to have higher SNR return signals, it is not necessary to rely on acceleration bins formed from an FFT array for signal detection. Close proximity targets with high SNR can often be detected in individual coherently integrated FFT templates, despite the likelihood of large acceleration uncertainty from higher angular acceleration rates.

Abstract: A signal-processing method for a motor-vehicle radar arrangement is specified, which method provides more extensive information on the traffic situation in observation direction by evaluating echo signals deflected at the road surface.

Abstract: The invention relates to a method for monitoring the earth's surface with a moving aircraft using a radar sensor with a synthetic aperture. In order to produce high resolution radar images, the flight parameters of the aircraft are also required. According to the inventive method, key parameters, such as speed and acceleration, are detected in the sight line of the radar sensor from the radio signals received. One of the advantages of the invention is that an inertial navigation system (INS) is no longer required for this purpose.

Abstract: A velocity calculating apparatus includes an acceleration sensor for detecting acceleration in the direction in which a motor vehicle travels. The acceleration sensor is connected to a CPU through an A/D converter. The CPU is connected to a GPS-signal receiver through a digital converter, and is also connected to a memory. The apparatus carries out a program for compensating for an error in the output signal of the acceleration sensor, wherein the program compensates the output signal of the acceleration sensor according to a GPS signal received from the GPS-signal receiver.

Abstract: In an obstacle recognition system for a vehicle, transmission wave is irradiated per given angle for recognizing an obstacle ahead of the subject vehicle based on angle/distance data obtained from received reflected wave. A position of the obstacle is estimated based on a previously recognized position of the obstacle. The estimated position of the obstacle and an actually recognized position of the obstacle are compared so as to determine whether the obstacle currently recognized is identical with the obstacle previously recognized. Relative acceleration is derived for the obstacle which has been determined plural times to be identical with the previously recognized obstacle. When the derived relative acceleration is outside a given range, the corresponding obstacle is excluded from objects of further obstacle recognition.

Abstract: Radar detection of accelerating airborne targets in accordance with the present invention utilizing a sequence of velocity, acceleration matched filters. This system includes a transmitter generating a signal oscillating at a predetermined frequency controlled by modulator such that the transmitter repeatedly outputs short duration pulses. The output pulse frequency is passed to an antenna that radiates the energy into free space. Reflected electromagnetic wave energy is received by the antenna to produce a radar return signal that is processed to a receiver that includes a radio frequency amplifier having an output that is mixed with a local oscillator signal an applied to an IF amplifier. An output of the IF amplifier is mixed with the output of an IF oscillator where the mixed signal passes through a low pass filter to a pulse compression network. An output of the pulse compression network is input to a matched filter processor array having multiple outputs applied to an adaptive threshold detector.

Abstract: An angular velocity calculating apparatus which is low-priced and capable of obtaining an angular velocity with high accuracy is realized. Two velocity detectors which are substantially small in offset error, noise, or the like, unlike the conventionally employed gyroscope, is disposed at portions on the moving matter or in the vicinity thereof, and the angular velocity is obtained on the basis of the velocity information obtained from these detectors. Accordingly, the angular velocity calculating apparatus and a navigation apparatus can be realized which is higher in accuracy and cheaper as compared with the conventional ones.

Abstract: A measurement device (103) and method determines various metrics between a vehicle (101) and a ground surface (105) using a transmitter-antenna (109) for emitting energy including a portion directed down toward the ground surface. A receiving antenna (115), has a portion oriented facing toward the transmitter-antenna for receiving a portion of the emitting energy along a direct path (117), and a portion oriented facing downwardly toward the ground surface for receiving a portion of the emitting energy reflected from the ground surface along a reflected path (113). A decoder provides separate indications of forward (121) and sideward (123) velocity relative to motion of the vehicle along the ground surface.

Abstract: A radar processor is described which performs acceleration compensation for accelerating targets. A set of matched filters is formed that compensates for each one of a predetermined set of target accelerations. The matched filters optimize the signal-to-noise ratio by weighting and combining the Doppler filters over which the target is spreading. As a result, enhanced detection capability of maneuvering targets that spread their energy over Doppler filters is provided. Radar processor loading is reduced, thus making practical the implementation of long coherent arrays.

Abstract: A Doppler radar speed detecting method in which periods of a Doppler signal are measured within a predetermined sampling time, and frequency data corresponding to the thus obtained period data are obtained. Upper and lower limit values are set based on the previous Doppler frequency F(k-1). The frequency data are compared with these limit values. Frequency data within a low region lower than the lower limit value, and intermedaite region between the lower and upper limit values, and a high region higher than the upper limit value are respectively counted in accordance with the comparison. Further, for the frequency data between the lower and upper limits, an integrated value of differences between these data and the previous Doppler frequency is obtained. From these integrated value and the numbers of frequency data, the change from the previous to the present Doppler frequency is calculated. By adding this change and the previous Doppler frequency together, the present Doppler frequency is obtained.

Abstract: A method of preventing interference between `friendly` pulse doppler radars when in action against a common target or adjacents targets. Despite considerable separation of the radar r.f's the pulsed signals have repeated sideband pulses which may be taken by another radar as a doppler-shifted echo. This problem is to a large extent alleviated by frequency modulating the r.f. transmission at a very low cycle rate of the order of one cycle per second and at a modulation rate sufficient to indicate to a receiving radar that the source could not be a target accelerating at such a high rate.

Abstract: A method of and apparatus for counting objects present within a predetermined area, by detecting acceleration and deceleration of the objects employ at least one Doppler radar to sense the movements of the objects by monitoring the Doppler frequencies of signals reflected from the objects, amplifying the Doppler signal reflected from each of the objects to provide an amplified signal, effecting an automatic gain control of the amplified signal to provide a signal of substantially constant strength independent of the distance and size of the respective object, detecting a frequency variation of the constant strength signal as an indication of change in the speed of movement of a respective one of the objects, determining whether the constant strength signal represents an acceleration or deceleration of the respective object, and correspondingly modifying a count representing the number of the objects in the predetermined area.

Abstract: Vehicles are measured and photographed from the direction in which they are travelling by a Doppler radar speed measuring device equipped with a camera. During a measuring stage after the vehicle enters the radar beam, a measured speed value is determined and when this exceeds a specific limit value, the camera is triggered. The Doppler signal for checking the measured speed value is then further evaluated over a verification distance. If the measured speed value is confirmed then it is printed on the photograph at the end of the verification distance, if it has not been confirmed, then a cancellation indicator is printed. The film is then advanced and the detection of the entry of another vehicle is awaited. As a result of this checking of the measured speed value, the measuring reliability when registering oncoming vehicles is substantially increased and overtaking in particular can be detected in the range of the radar beam.

Abstract: An adaptive learning controller (ALC) for use with an inertial navigation system (INS). To correct quadratic position errors which result from acceleration bias errors, the ALC produces a position correction signal. The position correction signal is generated by twice integrating an acceleration correction signal produced by the ALC. The ALC receives signals which indicate a current system state based on the corrected position signal and the velocity bias signal. The ALC also receives a failure signal determined by comparing the corrected position signal to predetermined failure criteria, these criteria relating to excursions of the corrected position signals beyond acceptable error limits.

Abstract: Accurate vehicle pitch and roll can be computed from a corresponding signal loop which receives inertial data input contaminated by the effects of gravity on a vehicle. Data from Doppler radar is compared to the inertial data and an error signal dependent on pitch or roll angle is substracted from the input inertial data resulting in the generation of accurate navigational parameters.