The Design And Implementation Of Wide-band Arbitrary Waveform Generator Platform

As the electronic system’s input stimulus,waveform generator is widely used in radar communication,electronic test,teaching and science research. With the development of electronic technology,the traditional waveform generator based on simulation method now can not meet our requirement to the output signal,and research on the waveform generator which can output arbitrary waveform of high stablility,wide band and quick parameter changing is now becoming the popular direction. Waveform generated by DDS(direct digital synthesis) technology is of precise phase and frequency resolution, which can also generate any waveform and realize parameter agility,so the research on realization of the wideband arbitrary waveform generator based on digital techonoly is of highly practical significance.A wideband arbitrary waveform generator(AWG) platform is designed and implemented in this dissertation.This platform is composed by software and hardware two parts.The host computer user interface is the software module,which can calculate and send waveform data to the hardware module.The hardware module is composed by a frequency module and a digital waveform generator,the frequency module is the clock source of the DAC.The main work in the dissertation is:1. Introduction of the related theory in the radar signal process and the comparing between the two kinds of waveform synthesis in DDS:DDWS and DDFS.According to their characteristics,the DDWS is chosen as the implementation scheme.2. Designing the UI on PC by the virtual insrtument software Labview.Waveform parameters can be input on it,such as the waveform kind,time duration,frequency width,number of quantization bits and so on.Waveform data is calculated on it and then downloaded to the AWG module by serial or ethernet dataline.3. Realization the function of the frequency module.This frequency module is the high speed clock to the DA and can output frequency ranging from137.5MHz-4400MHz,what’s more,the input parameters can be displayed on a LCD.4. Designing the AWG module.This AWG module is based on the DDWS technology,waveform data is downloaded to FLASHs on it and sent to the high speed catch SDRAMs by FPGA;then it is output to the DAC through4channels,every channel’s data rate is1Gsps;finally,the4channels’ data is mutplexed in DA and the generated signal’s data rate is up to4Gsps.