A device for determining distance and radial speed of an object relative to a measuring point, comprising:
- a first signal generator, coupled to a transmitting antenna or to another transmitting antenna, and configured to generate first transmission signals and to emit the first transmission signals from the transmitting antenna or the other transmitting antenna, the first transmission signals being radar radiation in a form of first frequency ramps;
- a second signal generator, coupled to the transmitting antenna or to the other transmitting antenna, configured to generate second transmission signals and to emit the second transmission signals, from the transmitting antenna or the other transmitting antenna, at the same time as the first signal generator emits the first transmission signals from the transmitting antenna or the other transmitting antenna, the second transmission signals being radar radiation in a form of second frequency ramps, the second frequency ramps differing from the first frequency ramps by a frequency offset difference (df);
- a receiving antenna, configured to receive, as received signals, reflections from the object of the first transmission signals and reflections from object of the second transmission signals;
- a mixer, configured to mix one among the first transmission signals and the second transmission signals with the reflections from the object of the first transmission signals and the reflections from the object of the second transmission signals, creating mixed signals, which include a result of mixing the one among the first transmission signals and the second transmission signals with the reflections from the object of the first transmission signals and of mixing the one among the first transmission signals and the second transmission signals with the reflections from the object of the second transmission signals;
- a bandpass filter, configured to pass, as passed mixed signals, a portion of the result of mixing the reflections from the object of the first transmission signals with the one among the first transmission signals and the second transmission signals, and a portion of the result of mixing the reflections from the object of the second transmission signals with the one among the first transmission signals and the second transmission signals;
- an analog-to-digital converter (ADC), configured to generate samples of the passed mixed signals;
- a digital signal processor, configured to receive the samples of the passed mixed signals, and to:
- generate a range-Doppler matrix based on computing a two-dimensional Fast Fourier Transform (FFT) using the samples of the passed mixed signals, the range-Doppler matrix including two peaks, one of the two peaks corresponding to the passed portion of the mixing of the reflections from the object of the first transmission signals with the one among the first transmission signals and second transmission signals, and the other of the two peaks corresponding to the passed portion of the result of mixing the reflections from the object of the second transmission signals with the one among the first transmission signals and the second transmission signals,
- detect, based on the two peaks in the range-Doppler matrix, two Doppler frequencies, each of the two Doppler corresponding to the radial velocity of the object, and the two Doppler frequencies differing from one another in correspondence to the frequency offset df, and
- determine the radial speed of the objection, based on one or more of the two Doppler frequencies, or a frequency information of the passed mixed signals obtained from the range-Doppler matrix, or both.