The Study And Development Of Multichannel Digital Frequency Conversion System Based On Time Sequence Reconstruction Technology

In order to meet target detection in complex electromagnetic environment,the active phased array radar has been widely used in target search,target recognition and other scopes,and has become an indispensable part of attack or defense system because of its advantages of rapid scanning,changeable control mode,flexible beam form and multi-target monitoring.Under the premise of miniaturization and multi-functions of phased array radar,the multi-channel digital frequency conversion system as an important part of connecting links between the preceding and following.With the rapid updating of highly integrated components and component-based software programming technology,the integration of multi-channel digital frequency conversion system has been greatly promoted,meanwhile,it possesses increasing receiving dynamic range,optimizing hardware layout integration,system design with digitalization and improving anti-jamming capability to make the multi-channel digital frequency conversion system more softwareized.Based on the technology of fusion FPGA time sequence reconstruction,a multi-channel digital frequency conversion system of active phased array radar is designed and developed according to the specific requirements of engineering input specifications.The multi-channel digital frequency conversion system uses time sequence reconstruction technology to construct the internal timing control relationship of the system.As the control reference of the system operation,the control circuit adopts the highly integrated complex programmable chip to core controller,and the mixed signal circuits layout is used in the hardware design,the PCB board adopts the mixed compression method for its structure,meanwhile,the multi-channel phase synchronization system is built and then the output signal phase control and signal mode control are realized for the multi-channel digital frequency conversion system.The system internal instruction transmission is controlled by parallel port mode,and the system external instruction transmission adopts optical fiber communication technology,and the designing application program of their related software is written in Verilog HDL language on the ISE software design platform to achieve the transmit/receive and control of instructions between different subsystems of the radar.In the stage of engineering realization,we test the multi-channel digital frequency conversion system through with special instruments,and verify that the hardware composition and software design of the system meet the expected requirements of the user.The engineering design is of great significance.