宽带频率合成器设计及应用  

Design and Application of a Wideband Frequency Synthesizer

作　　者：陈大海[1] 邓贤进[2] 张健[2] 

机构地区：[1]电子科技大学电子工程学院,成都610054 [2]中国工程物理研究院电子工程研究所,绵阳621900

出　　处：《电子测量与仪器学报》2008年第1期94-98,共5页Journal of Electronic Measurement and Instrumentation

摘　　要：设计并实现了一种能够覆盖C波段的宽带低相噪频率合成器。它基于改进的DDS+PLL组合频率合成方法。在较低频段利用DDS激励PLL方式来完成细步长,虽然有环路带宽内杂散恶化的问题,但由于倍频数N值很小,大大地避开了其缺点。然后通过PLL内插DDS方式,将频段搬移到高端,不但降低了PLL环路内带通滤波器的设计难度,同时可进一步抑制带外杂散。测试结果满足设计指标,证明了方案的正确性。另外,该频率合成器被成功地用于构造S波段多模式信号源,介绍了其原理和实验结果。A wideband low phase noise synthesizer that covers C band has been designed and implemented. It is based on an improved DDS ＋ PLL synthesis method. At lower frequency band, a DDS-driven-PLL synthesizer is applied to realize fine step length; although spurs inside the loop may become worse, but this situation can be greatly overcome due to the small value of frequency multiples of N. The output is then up-converted to higher frequency band with another PLL-offset-DDS synthesizer, in this way, not only the bandpass filter inside the PLL loop is easier to be implemented but also the spurs outside the passband are further suppressed. Test results are presented, which satisfy the required specifications and prove the correctness of the scheme. In addition, the wideband synthesizer has been used to build an S band multi-mode signal generator successfully; its design principle and experimental results are also introduced.

关 键 词：频率合成 宽带 DDS+PLL 信号源 

分 类 号：TN74[电子电信—电路与系统]