This paper presents a novel co-optimization configuration to simultaneously improve phase noise and FoM in order to solve the long-existing issue of excellent phase noise and mediocre FoM in the light of GaAs technologies. Considering traditional GaAs based Colpitts/class-C VCOs, a first step is taken with the introduction of noise shifting structure while a second step is carried out with the presentation of Darlington pair. Afterwards, a detailed outline of pros and cons of five VCO topologies, including Colpitts/class-C/noise shifting (NS) Colpitts/noise shifting class-C/noise shifting Darlington-based (NSDB) class-C VCO, is given in theory and in practice while respective start-up conditions and capacitive feedback factors are derived mathematically. It can be found that iterative phase noise and FoM improvement is achieved in GaAs based VCOs above in a gradual manner. Furthermore, the output power is stabilized with a simple trick of two-stage Darlington-based topology and thus, the power-hungry buffer is avoided. Ultimately, three VCOs out of the five are fabricated in GaAs technologies while their specifications are thoroughly compared with previous research. The fabricated Colpitts VCO demonstrates a frequency tuning range of 3.59–3.69 GHz with a current consumption of 11.2 mA@5 V supply, a phase noise of − 130.1 to − 129.1 dBc/Hz at 1 MHz offset from the carrier and the output power is around − 5 to − 5.1 dBm. The fabricated noise shifting Colpitts VCO demonstrates a frequency tuning range of 3.58–3.67 GHz with a current consumption of 10.8 mA@5 V supply, a phase noise of − 132.4 to − 130.2 dBc/Hz at 1 MHz offset from the carrier and the output power is around − 2.5 to − 3.5 dBm. The fabricated Darlington-based class-C VCO demonstrates a frequency tuning range of 2.76–2.91 GHz with a current consumption of 9.5 mA@5 V supply, a phase noise of − 138.6 to − 135.9 dBc/Hz at 1 MHz offset from the carrier and the output power is around − 3.06 to − 4.18 dBm. To the best of the authors’ expertise, the proposed Darlington-based class-C VCO achieves both exceptional phase noise and FoM, which far outweigh that of existing GaAs ones.

本文提出了一种新颖的协同优化配置，可以同时改善相位噪声和FoM，以解决GaAs技术长期以来存在的出色的相位噪声和中等FoM问题。考虑到传统的基于GaAs的Colpitts / C类VCO，第一步是引入噪声转移结构，而第二步是提出达林顿对。然后，在下面详细介绍了五种VCO拓扑的优缺点，包括Colpitts / C类/噪声转换（NS）Colpitts / C类噪声/基于Darlington的噪声转换（NSDB）C类VCO。理论和实践中，而各自的启动条件和电容性反馈因子则通过数学方法得出。可以发现，在上述基于GaAs的VCO中逐步实现了迭代相位噪声和FoM的改善。此外，通过基于达林顿的两级拓扑的简单技巧使输出功率稳定，从而避免了耗电的缓冲器。最终，五种VCO中的三种均采用GaAs技术制造，并且其规格与以前的研究进行了彻底比较。制成的Colpitts VCO演示了3.59–3.69 GHz的频率调谐范围，在5V电源下的电流消耗为11.2 mA，在距载波1 MHz偏移处的相位噪声为− 130.1至− 129.1 dBc / Hz。大约-5至-5.1 dBm。制作的噪声偏移Colpitts VCO演示了3.58–3.67 GHz的频率调谐范围，在5 V电源下的电流消耗为10.8 mA，相位噪声为− 132。从载波偏移1 MHz时为4至-130.2 dBc / Hz，输出功率约为-2.5至-3.5 dBm。基于达林顿制造的C类VCO展示了2.76–2.91 GHz的频率调谐范围，在5 V电源下的电流消耗为9.5 mA，在从载波偏移1 MHz时的相位噪声为− 138.6至− 135.9 dBc / Hz输出功率约为− 3.06至− 4.18 dBm。就作者的专业知识而言，所提议的基于达灵顿的C类VCO既实现了出色的相位噪声，又实现了FoM，远远超过了现有的GaAs。在距载波1 MHz处有9 dBc / Hz的偏移，输出功率约为− 3.06至− 4.18 dBm。就作者的专业知识而言，所提议的基于达灵顿的C类VCO既实现了出色的相位噪声，又实现了FoM，远远超过了现有的GaAs。在距载波1 MHz处有9 dBc / Hz的偏移，输出功率约为− 3.06至− 4.18 dBm。就作者的专业知识而言，所提议的基于达灵顿的C类VCO既实现了出色的相位噪声，又实现了FoM，远远超过了现有的GaAs。