THz time-domain systems driven by photoconductive antennas (PCAs) promise a bandwidth of the order of hundreds of GHz. This characteristic can be utilized to build see-through radars with sub-mm resolution and a field of view comparable to the current mm-wave radars at a relatively low cost. These radars can solve the issues in the field of public safety and security. However, the analysis and design of a THz time-domain radar is a challenging and time-consuming task even at the preliminary level. In this work, a Matlab based GUI is built that serves as a one-stop solution for the THz time-domain radar design and analysis. The GUI has three interfaces, the first one is the “Transmitter interface” which implements the Norton equivalent circuit of the PCAs and quantifies its radiated THz power along with other important parameters of the PCA semiconductor gap such as the conductance and current across the gap, and the resistance of the gap. The second interface, known as the “QO Channel Analyzer interface”, of the GUI tool analyzes a pre-defined QO channel model to estimate the power loss in the channel and the power received at the receiver. The third interface is the “Main interface” which analyzes the detection and imaging-related parameters of the radar such as the resolution, field-of-view, detection bandwidth and integration time.