Improved phase noise for dielectric resonators oscillators with broadband tuning

In this article, we describe a method of design of very low phase noise dielectric resonators oscillators at 13 GHz. By using two Silicon Germanium transistors with total gains 8 dB and lower flicker noise corner between 10 kHz and 40 kHz, the phase noise of the oscillators can be achieved −125 dBc/Hz at 10 kHz offset. The resonator has unloaded Q around 14,000 at operating frequency and is then optimized and coupled to the amplifiers for minimum phase noise where Q L / Q 0 = 1/2 hence S 21 = −6 dB. To incorporate tuning, phase shifter is also investigated. The phase noise measurement system is also presented using two identical oscillators phase locked at the same frequency.© 2009 Wiley Pe riodicals, Inc. Microwave Opt Technol Lett 51: 1312–1316, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24334