200 You Know Arbitrary Waveform Generator Digital Circuit Design

AS Arbitrary Waveform Generator has the advantages of high stability of output frequency, high frequency resolution, fast frequency switching, generating continuous phase waveform and being able to output the user-defined waveforms and so on, it is increasingly widely used in the test system. With the rapid development of electronic technology, the complexity and diversity requirements of instimulating signal of the test task is increasing. The requirement of diversity of the arbitrary waveform generator function is also increasing.Based on the above background, the requirement of developing a Multi-function200MSPS arbitrary waveform generator is proposed. This thesis is mainly to complete the digital circuit design of the arbitrary waveform generator. The main contents are as follows:1) Analyze the relevant indicators of digital circuits of the200MSPS arbitrary waveform generator and analyze the advantages and disadvantages of the DDWS and DDFS. Proposed the digital circuit scheme of arbitrary waveform generator of using these two methods to synthetic waveforms so that the Arbitrary Waveform Generator has the advantage of fast frequency switching when generating the ordinary waveform and has the advantage of keeping the Waveform details when generating the arbitrary waveform.2) Use dual-DDS structure to realize AM, FM, PM, sweep, ASK, PSK, FSK, and Burst function in the digital circuit. Use the orthogonal carrier wave signals generated by DDS method to realize the IQ modulation in the digital circuit. And the multi-band digital modulation such as BPSK, QPSK,8PSK,4QAM,8QAM,16QAM,32QAM and so on can be realized by using the IQ modulation.3) The clock circuit is designed to provide the clock signal ranging from10MHz to200MHz. This clock circuit is able to use the local reference clock source and the external reference clock source, which can automatically identify the external reference clock source and be able to provide the external with reference clock.4) The embedded system controller based on ARM9is designed to realize the functions including the local control of the instrument, communication with the host computer through the LAN and USB interfaces, loading and storing waveform data through U disk and some other functions. And the external modulation source input circuit and the trigger signal input and synchronization signal output circuits are designed.5) The functions and indicators of the digital circuit of the200MSPS arbitrary waveform generator have been tested. And the analysis of results proves the feasibility of the design.