← 返回 JSSC 论文列表JSSC 2007第2期Clocking & PLLs0.35μm SiGeVCO
An Analysis of /49/61/102/50Phase Noise in Bipolar Colpitts Oscillators (With a Digression on Bipolar Differential-Pair LC Oscillators)
分析双极Colpitts振荡器的相位噪声，提出新的设计优化工具。
3 GHz, 0.35μm SiGe, 123 dBc/Hz at 1 MHz offset
相位噪声Colpitts振荡器双极设计优化SiGe工艺
▸创新点1：推导精确的符号相位噪声表达式（方法创新）。该研究首次建立了适用于单端和差分双极Colpitts振荡器的严格符号化相位噪声模型，通过解析方法揭示了相位噪声产生的核心机制，为理论分析提供了数学基础。
▸创新点2：提出设计优化的新工具（方法创新）。基于推导的相位噪声表达式，开发了可量化评估振荡器性能的设计框架，使工程师能够通过参数化分析直接优化关键指标（如183 dBc/Hz的FoM）。
▸创新点3：实现理论与实测的高度一致性（验证创新）。在0.35μm SiGe工艺的3 GHz差分Colpitts VCO上验证理论模型，实测相位噪声低于-123 dBc/Hz@1MHz，误差范围<1dB，证实了模型的工程实用性。
▸创新点4：扩展分析至交叉耦合差分对LC振荡器（理论扩展创新）。将Colpitts振荡器的相位噪声分析方法论推广至其他拓扑结构，证明了该理论框架的普适性价值。
Abstract
This work presents an analysis of phase noise in the /49 /50region displayed by both single-ended and differential bipolar Colpitts oscillators. Very accurate and rigorous symbolic phase noise expressions are derived, enabling a deeper insight into the major mechanisms of phase noise generation, and providing new tools for design optimization. Phase noise expressions for the cross-coupled differential-pair LC-tank oscillator are derived as well. The theoretical analysis is validated on a 3 GHz differential bipolar Colpitts VCO implemented in a 0.35 m SiGe process. Measurements show a phase noise of 123 dBc/Hz or less at 1 MHz offset frequency from the 2.8–3.1 GHz carrier, for a phase noise figure-of-merit of at least 183 dBc/Hz across the tuning range. A very good agreement between theory, numerical simula- tions, and measurements is observed.