Implementation and Testing of Low Power FMCW S-Band Radar System Design for Small UAV

Abstract —The paper importantly discuss about design of low power Frequency Modulated Continuous Wave (FMCW) S-Band (~2.3GHz) radar system, and then the implementation and testing procedure. The main system of FMCW S-Band radar consists of a ramp generator, a Radio Frequency (RF) System, and an audio amplifier. The ramp signal is generated from IC XR-2206 (modulator). This ramp signal is connected to a voltage-controlled oscillator (VCO), one part of RF system, to produce a chirp signal with varying frequencies as a result of inclined voltage signal (ramp signal) generated by modulator. Besides VCO, in RF system there are also signal amplifier (either for transmitting signal or receiving signal), splitter signal (for transmitting purpose) and mixer (for receiving purpose). Audio amplifier consists of a gain stage/amplifier and two-stages 15 KHz active Low-Pass Filter (LPF) which are applied to process the signal from RF mixer’s output before being acquired through audio jack. At the front end of the system, two Vivaldi Antennas with 4dBi gain are installed and act as transmitter and receiver. The system is tested to detect simple corner reflectors placed in an area. The future application of this light weight and low power FMCW radar system is able to be mounted on a small Unmanned Aerial Vehicle (UAV) to do myriad tasks such as forest survey, crop monitoring, and reconnaissance.