High-resolution through-the-wall radar imaging (TWRI) systems can provide a high degree of situational awareness in urban sensing applications. However, such systems generate huge amounts of data, owing to the use of wideband signals and large arrays to achieve high resolutions in range and crossrange. This makes both data acquisition and processing challenging. In this paper, we present fast data acquisition and processing schemes for TWRI. We use compressive sensing and novel concepts of microwave tomography to establish a reduced-redundancy spatial and frequency measurement configuration, which provides clear advantages in terms of measurement time and algorithm complexity. Performance validation of the proposed strategy is provided using laboratory experiments.