The Defense Support Program (DSP) is a US active early warning satellite system that conducts early detection and early warning of missiles. In order to analyze the target detecting ability of DSP satellites, this paper analyzes the deployment situation and working mode of the early warning satellite, and proposes the general framework of the early warning satellite simulation system which determines the functional modules and the realization mode of the system. According to the double-band detection mode of the early warning satellite, this paper proposed an infrared two-color scanning detection model. In this model, First a multi-frame correlation target detection algorithm based on double-Hough transform is proposed, which can effectively remove the background noise, then combines the information fusion strategy reducing the false alarm rate, and finally using double-star positioning function to estimate the trajectory of target, in the meantime the error between the predicted trajectory and the real trajectory is analyzed. This simulation system has gets the expected results, having the capabilities for detection and tracking the missile, and provide a means of simulation and basis for performance evaluation.