Abstract— This paper describes two approaches to short-range
microwave imaging by means of ultra-wideband (UWB)
technology. The first approach deals with synthetic aperture
radar (SAR) that employs a transmit-receive antenna pair on
mechanical scanner. The second one represents a multiple input
multiple output (MIMO) antenna array that scans electronically
in the horizontal plane and mechanically, installed on the
scanner, in the vertical plane. The mechanical scanning in only
one direction reduces significantly the measurement time. Two
respective prototypes have been built and compared. Both
systems comprise the same 10-18 GHz antennas and multichannel
video impulse electronics while the same focusing based
on Kirchhoff migration is applied to acquired data for radar
imaging. The study has been carried out for an application of
concealed weapon detection.