Variable Frequency Radar Signal Generator Signal Generating Module Of The Design

The radar signal generator is used to simulate the radar echo signal, which makes that the post stage of radar system is debugged without the former stage ture. In traditional radar signal generator, the phase-locked frequency synthesizer technology is used. Due to the existence of frequency preset time and lock time, its frequency agility speed is not very high.With the target more and more complex, more performences of radar signal are needed, such as the ability of fequency agility. The frequency agile radar signal generator cames into being.The design of signal generation module is discussed in this paper, which is from the project of "frequency agile radar signal generator". In this project, the frequency agile time is required less than100ns. And the system can be operated at frequency guided mode and self-produce mode. Contents of this paper are as follows:1. Aim at the requirement of frequency agile time in this project, the advantages and disadvantages of the three frequency synthesizers are analyzed, and finally the direct digital synthesis (DDS) technology is adopted to design the signal generation module.2. The sampling rate and implementation of the DDS are determined by analyzing the working principle, the output spectrum characteristics and the main source of error of DDS, combined with the indicator requirement and the device status. For the bottleneck of the current device’s working speed, the parallel storage technology is used to breakthrough its limit and achieve a high sampling rate.3. The overall design scheme of signal generation module is put forward. The type of relevant device is determined, and the clock generator, the DDS module, the signal conditioning module and other key part of the design are discussed in detail.4. The logical design of signal generation module is put forword. The function and indicator of sweepwave and frequency-hopping wave are analyzed, and the frequency control module is designed, completing the frequency control of these two waveforms. 5. The appropriate methods are used to test the system. And the design is proved correct by analyzing the test data.