4-8GHz宽带DDS锁相扫频源的研制

【作者】 赵宏飞；

【导师】 张玉兴；

【作者基本信息】 电子科技大学 ， 电路与系统， 2002， 硕士

【摘要】 本课题来源于与天津中源仪器设备公司的合作项目：4～8GHz频谱分析仪，电子科技大学负责其中的4～8GHz宽带扫频源部分。课题的最终实现方案采用了DDS+PLL+倍频+混频等综合频率合成技术，该方案不论是在技术上还是在一些具体模块电路的实现上都具有一定的创新与独到之处。 课题中所采用的DDS+PLL频率合成方法可以将DDS的超高频率分辨率、高频率精确度、容易实现程控等优点与锁相环良好的窄带跟踪滤波特性相结合，从而实现系统所要求的宽带扫频功能及相应的技术指标。 本文首先介绍了扫频源的相关原理，接着简述了频率合成、锁相环频率合成、DDS频率合成、DDS+PLL频率合成等的基本理论以及具体的系统设计中应该考虑的方面。然后就本课题所涉及到的内容简要介绍了一些微波固态频率源方面的知识。最后详细叙述了本课题采用的方案、各个模块的功能实现、实际设计中应该注意的问题以及最终系统的测试结果。更多还原

【Abstract】 The subject derives from the project of "4 ~ 8GHz spectrum analyzer", which is collaborated with TianJin ZhongYuan instrument and equipment Inc., and UESTC (University of Electronic Science and Technology of China) undertake the 4~8GHz Wideband Sweep Source in this project. The integrative frequency synthesis technology of DDS+PLL+Douber+Mixer is adopted in the final scheme. The scheme is innovative and original not only in the technology but also in some module circuit.The hybrid frequency synthesis technology----DDS + PLL used in thesubject have many advantages. Using this method, the merits of DDS such as super fine frequency resolution ? high frequency accuracy -, easy programmed can be in combination with the excellent character of narrow-band tracing filter merits of PLL. Thereby, the wideband sweep function and specification of the system can be realized.The principle of sweep source is introduced at first in this paper. Subsequently, the basic theory and some question about the concrete design of the system on frequency synthesis^ PLL^ DDS> DDS + PLL are discussed. And then some contents about Microwave Solid-State Source which is related to the subject are introduced. At last, the scheme of subject, the functional realization of each module, some questions which must be pay much attention in the system design, and the ultimate testing result of this subject is represented and analyzed in detail.更多还原