Research On Simulation Generating Technology Of Radar Transmitting Waveform

With the form of increasing complexity of modern electronic warfare, the performance requirements of electronic equipment gradually improving, is no longer limited to meet the basic functions of the system. Radar indispensable as an electronic device on the electronic battlefield, plays a key role, the radar signal source as an important part of the radar system, its stability and reliability directly affect the performance of the radar system, and high-performance parameters of the radar signal source bound to the requirements of modern radar. Radar by transmitting and receiving electromagnetic signals to ascertain the relevant information of the target object, and the electromagnetic signal transmitted by the radar signal source is mainly generated by the radar system of the radar systems of different styles and transmitted waveform parameters vary, the use of frequency synthesis technology produce radar signal source is a very effective solution to the current development of electronic technology, the frequency synthesis technology in direct digital frequency synthesis(DDS) is a very good overall performance frequency synthesis method, but it still exists stray a little spurious and shortage.This paper begins with the analysis of the characteristics common radar waveform and makes the relevant simulation, followed by an overview of frequency synthesis, analytical technology, the basic principles of DDS, is derived from the theoretical paper analyzes the problem of stray DDS, summed up the generation DDS spurious noise sources. Firstly, the output signal spectral characteristics in the ideal case, followed by theoretical derivation of the phase accumulator truncation effect on the output signal, by increasing the phase accumulator wide or reduce the stray's digits can be improved DDS, and then analyzes the DAC quantization error on the amplitude of the output signal, or by increasing the bit-wide phase accumulator or increasing quantization bit number can improve the DDS stray, and then make a summary of DDS spurious issues, followed on the DDS spurious suppression technology research and simulation. Then on the DDS spurious suppression technology research and simulation, we discuss the random phase jitter method can effectively suppress spurious caused by the phase accumulator truncation. It describes the key indicators and frequency synthesis radar signal source. Finally, this paper for a dedicated DDS chip AD9914 development and application, according to its features, the use of FPGA design AD9914 controller for analog control AD9914 single-frequency signal previously studied, the chirp signal and the phase encoded signals, and discusses frequency Agility signal generation process. By Vivado software AD9914 controller encapsulates IP core, and discusses the application controller, and finally for radar signals to make simulation analysis.