基于锁相环技术的X波段频率源的研制

Design of X-Band Frequency Synthesizer Based on PLL

介绍了一种X波段频率源的设计方案及相关理论。采用数字锁相环内混频技术实现的该X波段频率源具有频带宽,相位噪声低,杂散低等特点。其主要技术指标如下:输出频率范围为9.8GHz～10.8GHz,频率步进为5MHz,在偏离1KHz处相位噪声优于-85dBc/Hz,在偏离10KHz处相位噪声优于-88dBc/Hz,杂散抑制优于60dBc。由最后的测试结果可知,采用该方法设计的频率源既能保证低杂散又能显著改善相位噪声水平,可广泛用于通信设备和测试系统中。

The design method and correlated principles of a X-band frequency synthesizer are described.This frequency synthesizer with wide frequency coverage,low phase noise,and low spurious is achieved by combining Phase locked loop(PLL) and mixer.Main technical specifications of the frequency synthesizer are as follows:frequency range of 9.8GHz～10.8GHz,frequency step of 5MHz,the phase noise is better than-85dBc/Hz@1kHz,-88dBc/Hz@10kHz,and spurious suppression is better than 60dBc.The final test result proves that this frequency synthesizer not only can ensure low spurious but also improve the phase noise level.It can be widely used in communication and test systems.