A Low Phase Noise Differential Oscillator Employing Stub-Loaded Nested Split-Ring Resonator Inspired Balanced Bandpass Filter
- Resource Type
- Conference
- Authors
- Cai, Zongqi; Tang, Xiaohong; Li, Zhiyou; Zhang, Ting; Liu, Yong; Yang, Yang
- Source
- 2019 IEEE MTT-S International Microwave Symposium (IMS) Microwave Symposium (IMS), 2019 IEEE MTT-S International. :967-970 Jun, 2019
- Subject
- Components, Circuits, Devices and Systems
Computing and Processing
Engineering Profession
Fields, Waves and Electromagnetics
Photonics and Electrooptics
Phase noise
Band-pass filters
Resonator filters
Microwave filters
Couplings
Frequency measurement
Balanced filter
differential oscillator
group delay
Low phase noise
SLNSRR
- Language
- ISSN
- 2576-7216
This paper presents a low phase noise differential oscillator by employing a balanced feedback bandpass filter (BPF) designed with the proposed stub-loaded nested split-ring resonator (SLNSRR). The proposed balanced BPF functions as a frequency stabilization element in its feedback loop. Taking advantage of the balanced structure, a high group delay is obtained by introducing a transition zero near the upper passband of feedback loop filter. The proposed differential oscillator can present a differential output with low phase noise performance. For proof of the concept, a 2 GHz differential oscillator has been designed, fabricated and measured. The measured results show that the 180 o out-of-phase differential signals are obtained with almost the same peak-peak voltage among two channels. The output power is 9.18 dBm when oscillates at 2.004 GHz with the second harmonic suppression of 40.63 dB. The measured phase noise is -126.72 dBc/Hz at 100 kHz frequency offset. The figure-of-merit (FOM) at 100 kHz is -196.19 dBc/Hz. The phase noise performance of proposed differential oscillator is one of the best among open literatures.