Because of the advantage in target detecting, target identifying and anti-jamming, the UWB radar technology has been applied to more fields. It is very important to apply the UWB radar technology to the aerial defence missile for military aim. How to gain bigger cooperative efficiency between fuze and warhead of missile is a pivotal technology problem. The problem can be solved if we can make use of the information of target echo and the relative speed of target and missile well. With the information of target echo in the encountering course of target and missile, the distance value and angle value of target can be estimated. The time domain characteristics of short range target body echo of UWB array are analyzed based on the Gaussian impulse. The mathematical relations between the pulse duration and the most radiation direction of UWB array, the angle of target position are brought forward. A way for angle estimation using pulse duration of target echo is proposed. And the method of improving the cooperation efficiency of fuze and warhead of missile is educed based on the echo information of UWB array and the relative speed between target and missile. So the best explosion location of warhead of missile for killing target can be calculated. Through simulation and calculation, the feasibility of the new method is verified.