多环小步进频综杂散分析与设计

Analysis and Design of the Spurs in the Multiple-loop Small Step Size Synthesizer

对多环混频锁相式小步进频综的杂散和相噪等关键指标进行理论分析,对杂散规律、杂散电平及杂散频率给出简单、有效的工程数学方法。在此基础上设计实现S/C频段宽带小步进高性能频综,带宽分别为500MHz/1300MHz,杂散电平<-75dBc。

This paper presents the theoretical analysis of the spurs and phase noise in the multiple-loop small step size synthesizer.Based on the fundamental analysis,the unique design methods of the spur rules,spur levels and spur frequency are proposed by combining rigorous mathematical calculating methods for formulas with actual measured data.A broadband small step size synthesizer with high performances operating at S/C bands is designed.Its bandwidths are 500MHz and 1300MHz respectively.And its spur level is lower than-75dBc.