The Design of a 50MHz Colpitts Low Phase Noise Crystal Oscillator Based on ADS Simulation
The importance of loaded quality factor QL is analyzed on the basis of Leeson model and the formula of QL is derived from the analysis of Colpitts oscillator circuit. According to the results, we can draw a conclusion that QL is explicitly related to circuit parameters. The phase noise of the SOMHz Colpitts crystal oscillator is simulated by the Agilent Advanced Design System (ADS). Based on the simulation results, a design of the prototype crystal oscillator is presented. The crystal resonator we use is AT-cut 3rd overtone crystal resonator with 49U resistance welding package, its unloaded quality factor Q0 is about 1.45 ×105. The measured results of phase noise are -107dBc/Hz@10Hz, -134dBc/Hz@100Hz and 152dBc/Hz@lKHz. Experimental results show that it is feasible to design low phase noise crystal oscillators on the basis of improving QL.
Leeson model loaded quality factor phase noise Colpitts crystal oscillator
Yan Wang Xianhe Huang
School of Automation University of Electronic Science & Technology of China Chengdu, China
国际会议
海口
英文
313-315
2011-07-15（万方平台首次上网日期，不代表论文的发表时间）