Indoor THz Synthetic Aperture Radar (SAR) is an emerging research domain. It expands the conventional SAR applications to sub-mm resolution imaging and localization due to high available bandwidth and compact antennas at this spectrum. In general, high resolution is always preferred but it comes with the cost of complexity of the radio front-end chain. Therefore, in this paper three SAR systems with different carrier frequency fc and bandwidth Bw are studied. These systems are set-up with fc = 230 GHz and Bw = 20 GHz, fc = 245 GHz and Bw = 50 GHz and lastly, fc=275 GHz and Bw = 110 GHz. The paper presents the comparison between these systems w.r.t. the focused SAR image quality associated with the spatial resolution.