本设计采用AT89S52为控制核心，以DDS芯片AD9850产生频率可以自动可调的正弦扫频信号，实现了全频范围和特定范围内自动搜索和手动搜索，并且鉴别外来信号的调制方式：调频、调幅、等幅。通过单片机自动显示外来信号频率并存储，达到侦察接收机的性能要求。-AT89S52 the design for the control of the core, have a DDS chip AD9850 automatically adjustable frequency swept sine signal, to achieve the full frequency range and a specific range of automatic search and manual search, and identification of external signal modulation: FM, AM, amplitude. Through the single-chip external signal frequency automatically display and storage, to achieve the performance requirements of the reconnaissance receiver.