In this paper, we consider the problem of detecting and localizing static objects in a room using thoughwall ultra-wideband (UWB) radar SAR measurements. This paper investigates basic inversion (imaging) techniques which are used for interpreting the raw radar data in an understandable way. We also introduce a fast method for estimating the travel time between the antennas and the targets. The accuracy and computational complexity of the imaging techniques are analyzed and compared.