In this letter, an ultralow phase-noise differential oscillator is proposed using a balanced feedback filter based on quarter stepped-impedance resonators (QSIRs). Phase-noise performance of the designed oscillators can be significantly improved by taking advantage of high peak group delay, improved stopband suppression, and differential configuration of the proposed feedback filter. To verify the hypothesis and compare the phase-noise performance among single-ended and differential oscillators, both the prototypes are designed, fabricated, and measured. The measured results show that the designed single-ended and differential oscillators are operating at 1.953 GHz. The differential oscillator shows not only a good balanced output power of 8.29 dBm with a measured high suppression of 40.07 dB on the second harmonic but also a superior low phase-noise performance of −130.19 dBc/Hz at a frequency offset of 100 kHz. To the best of our knowledge, this is the best phase-noise performance among the state-of-the-art works designed on planar hybrid integrated circuits at a similar frequency range.

中文翻译：

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使用四分之一阶跃阻抗谐振器的超低相位噪声差分振荡器

在这封信中，提出了一种使用基于四分之一阶跃阻抗谐振器 (QSIR) 的平衡反馈滤波器的超低相位噪声差分振荡器。通过利用高峰值群延迟、改进的阻带抑制和所提出的反馈滤波器的差分配置，可以显着提高所设计振荡器的相位噪声性能。为了验证假设并比较单端振荡器和差分振荡器的相位噪声性能，设计、制造和测量了这两个原型。测量结果表明设计的单端和差分振荡器工作在 1.953 GHz。差分振荡器不仅显示出 8.29 dBm 的良好平衡输出功率和 40 的实测高抑制。07 dB 的二次谐波，而且在 100 kHz 的频率偏移下具有 -130.19 dBc/Hz 的卓越低相位噪声性能。据我们所知，这是在类似频率范围内在平面混合集成电路上设计的最先进作品中最好的相位噪声性能。