An FMCW radar architecture was chosen because of its
simplicity. It is not difficult to generate slow 20 ms wideband
linear FM chirps using a voltage controlled oscillator
(VCO) and a ramp generator, then de-chirp down to audio
frequency range which can be digitized inexpensively using
the audio input port of a laptop computer. The center frequency
is 2.4 GHz with a chirp bandwidth adjustable up to 330
MHz. An equivalent short pulse radar system would require
a significantly more complicated (and expensive) wide-band
digitization system.