Continuous wave frequency modulated radar imaging

Abstract

Continuous wave frequency modulated (CWFM) radar systems are a low-cost alternative to the more traditional pulsed radar systems, and are ideal for shortrange, low-power applications. An X-band CWFM radar system based on a commercially available low-cost Doppler radar module and using a linear frequency modulation was successfully developed and characterised. The system was operated both as a range-time-intensity (RTI) system and as a synthetic aperture radar (SAR) system. The performance and characteristics of the system were tested in both indoor and outdoor environments where different considerations of clutter and multipath apply. Signal processing techniques were implemented to improve the imaging quality and also extract target velocity (Doppler shift) information. The limitations of the system are discussed and possible improvements regarding both the hardware and the processing procedures are suggested based on the observations made.222