The 2-D imaging will be realized by using single-frequency radar, when the target executes 2-D rotation relative to the radar. Especially when the target rotates around two orthogonal rotation axes which are both perpendicular to the radar line-of-sight, therefore the projection image plane is perpendicular to the radar line-of-sight, the image whose angle of sight is similar as photographic camera will be obtained. The principle of 2-D imaging using single frequency radar is analyzed. The single frequency THz(at 1.5 THz) radar echo from a tank model is simulated by using GRECO(Graphical Electromagnetic Computing) software. The side view of the model is obtained through 2-D azimuth compression using Fast Fourier Transform(FFT).