System description of a stepped frequency CW radar for humanitarian demining

A multiple frequency stepped frequency continuous wave radar for detecting flush buried and surface laid antipersonnel landmines was designed and built. The system covers a frequency band from 400 MHz up to 4845 MHz. The range resolution is 3.4 cm and the maximum unambiguous range is 4.3 m. The antenna configuration is a bistatic one with two Archimedean spirals with opposite sense of rotation. The instrumented dynamic range is 40-50 dB per frequency channel. After synthesis of the range profile the dynamic range is significantly higher. The system parameters are aimed at imaging algorithms exploiting the phase evolution over the antenna footprint in particular. One example of the results achieved with and without synthetic aperture radar processing is presented.