Radar sensor signal acquisition and multidimensional FFT processing for surveillance applications in transport systems

The design and test of a Radar sensor signal acquisition and processing platform is presented in the paper. The Radar sensor operates in real-time and is suited for surveillance applications in transport systems. It includes a front-end with a continuous-wave frequency-modulated transceiver operating in X-band, with a single transmitter and multiple receivers, and a multi-channel high-speed A/D converter. Sensor signal processing and data communication tasks with external hosts are managed by an FPGA (Field Programmable Gate Array). The signal processing chain includes region of interest selection, multi-dimensional FFT (Fast Fourier Transform), peak detection, alarm decision logic, data calibration and diagnostic. By configuring the Radar sensing platform in low-power mode (7 dBm transmitted power) it is possible to detect still and moving targets with a covered range up to 300 m and 30 cm resolution. The measuring range can be increased up to 2 km by adding an extra 34.5 dBm power amplifier. The Radar sensing platform can be configured for a maximum detected speed of 200 km/h, with a resolution of 1.56 km/h, or a speed up to 50 km/h with a resolution of 0.4 km/h. The cross-range resolution depends on the number of receiving channels; a trade-off can be found between cross-range resolution of the Radar sensor and its complexity and power consumption. With respect to the state-of-the-art of surveillance Radar sensors and Lidars, the proposed solution stands for its high configurability, and for the better trade-off that can be found in terms of covered distance and power consumption