Abstract: A new type wideband high resolution imaging radar is introduced, which employs many new technologies, such as multiple wideband high power TWTs , sub-array feeding network and time-delaying ISAR test system. The features of system design ,the principle and methods of its experimental study are introduced in detail. The result of range test is also presented. We analyzed the Stretch method for wideband signals and compensation for system distortion in matched filter in I and Q channels with 1GHz sampling frequency. The results of range experiments demonstrate that the range resolution can be less than 0.3 m and satisfactory two-dimensional image of civil plane can be acquired with these two methods.