SDR-based Speed Measurement with Continuous-Wave Doppler Radar

This paper presents a single frequency Continuous-Wave Doppler Radar capable of estimating the velocity of mobile agents. This kind of radar can be implemented at less complexity and a relative low cost by using Software Defined Radio (SDR). Moreover, open source software (GNU Radio) and hardware (Adalm-PlutoSDR) are used because of their flexibility in operation and integration. Compact parabolic antennas operating at 5.5 GHz are employed for radar signals transmission and reception. From the obtained signal in reception, further low pass filtering and Fast Fourier Transform (FFT) is performed in order to measure the Doppler shift. Experiments were performed using a car as the moving target taking advantage of its speedometer for measurements and error determination. The theory of the Doppler mathematical model is verified showing error calculation over the obtained results from theory and the realized tests.