Dds Signal Generator And Design

Signal generator is very important in modern electronic instruments. In the experiments, product development and debugging and system testing is essential, and the traditional signal generator performance is very limited, can not meet the requirements of some users. Direct Digital Synthesis is the new generation of frequency synthesis technology, it uses the numerical control signal the phase increase technology, has the frequency resolution high, the frequency cuts quickly, when frequency cut the phase continuously low as well as the entire digitization is easy with the phase noise to integrate and so on the merit is widely used. In recent years the super velocity digital circuit development as well as to the DDS thorough research, the DDS highest operating frequency as well as the noise performance approached and achieves the phase-lock frequency synthesizer suitable level. Along with this kind of frequency synthesis technology development, already widely applied to the communication, the navigation, the radar, remote control telemetering, electronic countermeasure as well as modernized do main and so on instrument measuring appliance industry.This article in the analysis existing signal generating device principle of work foundation, reasonably has used the DDS technology according to the system target, take the AD9854 chip as the core, by Atmel Corporation's monolithic integrated circuit chip AT89S52primarily controlling machine, has designed one kind of structure simple performance fine signal generating device. This signal generating device has the output frequency accurately, the frequency stability high, the frequency resolution high-frequency convers ionrate quick, produces the modulation signal, the suppression is good and so on the characteristic. This article completes the main work has:(1)Compared with the many kinds of signal generating device principle of work, analyzes their good and bad points, finally has determined take the DDS technology as the core development signal generating device plan.(2)Compared with the different type DDS chip characteristic, has chosenAD9854, and as the core has carried on the signal generating device system design, the hardware design, the panel and the realization take AD9854. (3)Used the C51 language to carry on the software design and the realization for monolithic integrated circuit AT89S52, and carried on the control to AD9854 then to be allowed to produce each kind of signal.(4)Carries on the debugging and the test to the system, enables the system to achieve the design target demand, and makes the elaboration to the system improvement.