Vehicle distance data processor A vehicle distance data processor precisely correlates or matches points of detection in a time serial manner to thereby accurately determine distances of a subject vehicle to a plurality of other vehicles or obstacles lying ahead as well as relative velocity vector data indicative of a velocity vector of each of the other vehicles or obstacles relative to the subject vehicle. Currently obtained coordinate data is correlated or matched with previously obtained coordinate data by means of a matching element 5A on the basis of coordinate data obtained by a distance data converting element 3A, reflection strength data obtained by a distance data/reflection-strength data input element 2A, and predicted coordinate data obtained by a coordinate data predicting element 4A. FM-CW radar system In an FM-CW radar system, a beat signal is frequency-analyzed for selecting ascending-side beat frequencies and descending-side beat frequencies for a plurality of targets. By pairing the ascending-side and descending-side beat frequencies one by one from each side, all possible combinations thereof are prepared. Based on these beat frequency combinations, beat frequency combinations after a given time are predicted, respectively. If an ascending-side beat frequency and a descending-side beat frequency of the predicted beat frequency combination are found in ascending-side beat frequencies and descending-side beat frequencies of a beat signal selected after the given time, respectively, or in the neighborhood of them, respectively, the predicted beat frequency combination of the found ascending-side and descending-side beat frequencies is set as a correct beat frequency combination. A further correct beat frequency combination/combinations can be set in the same manner. Based on these correct beat frequency combinations, information about the targets can be correctly achieved. Radar equipment and method for its operation A cost-effective FMCW radar equipment has a digital signal processor which controls at least one antenna through an oscillator and produces a mixed signal from transmitted and received signals modulated with a triangular waveform. The mixed signal is subjected to Fast Fourier transformation for each modulation phase (up and down) of each measurement cycle in order to obtain object frequencies, which are assigned to each target object, from the determined maxima. Object tracks which are formed from the object frequencies extend back over a plurality of measurement cycles and are used to form estimated values for those measured values of the object frequencies which are to be expected in the next measurement cycle. The mutually associated object frequencies of both modulation phases of a measurement cycle are determined and the distance and relative speed of each target object are determined from them. Object detecting system An object detecting system detects an object using an FM-CW wave, so that even if either one of rising-side and falling-side peak frequencies is missing, a plurality of objects can be accurately recognized by accurately combining pluralities of rising-side and falling-side peak frequencies. When it is determined that either one of rising-side and falling-side peak frequencies is missing, the combination of the peak frequencies is determined by calculating the missing peak frequency based on a peak frequency which is not missing. FM-CW radar system for measuring distance to and relative speed of a target An FM-CW radar is provided which may be employed in anti-collision systems or cruise control systems installed in moving objects such as automotive vehicles. The radar produces a first spectrum using a portion of a beat signal in a frequency rising range wherein the frequency of the radar wave increases and a second spectrum using a portion of the beat signal in a frequency falling range wherein the frequency of the radar wave decreases and moves the second spectrum by frequency shifts which are determined as a function of the speed of a radar-mounted vehicle and corrected for compensating various errors involved in measuring the speed of the vehicle to form spectrum groups each consisting of the frequency components moved by one of the corrected frequency shifts and frequency components in the other of the first and second spectra. The radar selects an optimum one of the spectrum groups for use in determining target data. FM-CW radar system for measuring distance to and relative speed of target An FM-CW radar is provided which may be employed in anti-collision systems or cruise control systems installed in moving objects such as automotive vehicles. The radar analyzes a beat signal in frequency to produce peak frequency components in a modulated frequency-rising range wherein the frequency of a frequency-modulated radar wave transmitted from the radar increases and a modulated frequency-falling range wherein the frequency of the radar wave decreases. If one of peak frequency pairs, each of which is made up of each of the peak frequency components in the modulated frequency-rising range and one of the peak frequency components in the modulated frequency-falling range, lies within a given lower frequency range, the radar identifies the one of the peak frequency pairs as radar data arising from a moving object appearing suddenly in a radar detection zone. Method of detecting moving and/or stationary objects in the path of a vehicle A method is described for detecting moving and/or stationary objects in the path of a vehicle, where the distance and velocity of the reflecting object are determined by using a radar sensor, where the frequency of the signal transmitted is modulated in the shape of a ramp according to a multi-ramp method, and some ramps have a lower slope in the frequency curve. The higher spectral components of the mixed signals from the ramps having the lower slope, which are to be assigned to a distance range of the reflecting object which is greater than the distance range belonging to the ramps having the greater slope, are used to determine the distance, speed and angle of objects. System for measuring the distance and the relative velocity between objects System for measuring the distance and the relative speed between objects using electromagnetic waves, having means for emitting electromagnetic waves from a first object and having means for receiving reflected electromagnetic waves from at least one second object, the frequency of the emitted signal being modulated in such a way that the modulation frequency, during a first time segment, increases approximately linearly from a first to a second modulation frequency value, that the modulation frequency, during a second time segment, is approximately constant, that the modulation frequency, during a third time segment, decreases approximately linearly from the second to a third modulation frequency value, that the modulation frequency, during a fourth time segment, is approximately constant, and that these time segments recur repeatedly, at least one of the modulation frequency values and/or the duration of at least one time segment being changeable. Method and apparatus for detecting multiple objects with frequency modulated continuous wave radar A method and an apparatus for multiple object detection by automotive FMCW radars provides distance and relative velocity information. A two chirp frequency sweep with small slope difference is utilized and, since the difference is small, the distance information can be obtained by automatically eliminating the Doppler frequency. Therefore, the distance and the relative velocity information for each of multiple objects can be calculated without ambiguity. Method for measuring the distance and speed of objects A method for measuring the distance and speed of objects using electromagnetic waves with a motor vehicle radar system is described, electromagnetic waves being transmitted and simultaneously received, the transmitted electromagnetic waves being modulated in the shape of a ramp, at least the signals received during one rise and one drop of the frequency of the transmitted signal being mixed in each case with the transmitted signal, a number of intermediate frequency signals being formed, and the distance and speed of the object being calculated using the intermediate frequency, a weather condition in the vicinity of the motor vehicle and/or a disturbance in the motor vehicle radar system being identified on the basis of characteristic intermediate frequency signals.