It describes the system design and software and hardware control and realization of a ground-based beam direction detecting system which is verified through injection simulation system by using power detector in this article. Through inputting simulated power signal from different satellite positions, and angle and position information of target satellite in the platform coordinates system into the injection simulation system, on one hand the ground-based detecting system technical solution feasibility can be defined and relevant detecting devices tested, on the other hand it can verify whether the detection capability against target satellite transmission antenna main lobe can meet the accuracy requirement. The simulation test results have proved the facts that the injection simulation system is easy for operation and cost effective, and through controlling relevant devices can it also record accurately the calculation information on target satellite simulation data which is carried out by the ground-based detecting system.