The use of ultra wideband radar for security systems is of interest because of the high range resolution. Much research has focused on developing effective methods for detecting, locating, tracking and imaging a human body with multiple radar systems. One important challenge in this field is how to handle data for multiple targets, because many conventional algorithms assume only a single target. In this paper, we propose a technique for separating two people walking using the texture of the time range image. This method calculates the image flow angle that depends on the motion and velocity of the target. We demonstrate that the proposed method can separate two people walking in opposite directions in the measurement.