Low Phase Noise Frequency Sources Research Articles

Design of the X-Band Frequency Source Based on the Multiplying Technology

The phase noise performance of frequency source has a direct impact on the target measurement such as the adjacent channel interference of the electronic system, the transmission quality of information, the resolution of radar. In this paper, we achieved an X-band high stability, low phase noise frequency source which based on the DDS combination with frequency doubling technology. The test result shows that when the output of the frequency source is at 8.544GHz, the phase nosie is-103.58dBc/Hz at 1kHz and-101.94dBc/Hz at 10kHz.

A V-Band Monolithic AlGaN/GaN VCO

A V-band push-push GaN monolithic microwave integrated circuit voltage controlled oscillator (VCO) has been realized based on a 0.2 mum T-gate AlGaN/GaN high electron mobility transistor technology with an fT ~ 65 GHz. The GaN VCO delivered an output power of +11 dBm at 53 GHz with an estimated phase noise of -97 dBc/Hz at 1 MHz offset based on on-wafer measurement. To the best of our knowledge, this is the highest frequency VCO ever reported for GaN technology with a high output power at V-band, without using any buffer amplifier. This work demonstrates the potential of applying GaN technology to millimeter wave band, high power, and low phase noise frequency sources applications.

A Q-band low phase noise monolithic AlGaN/GaN HEMT VCO

A Q-band 40-GHz GaN monolithic microwave integrated circuit voltage controlled oscillator (VCO) based on AlGaN/GaN high electron mobility transistor technology has been demonstrated. The GaN VCO delivered an output power of +25dBm with phase noise of -92dBc/Hz at 100-KHz offset, and -120dBc/Hz at 1-MHz offset. To the best of our knowledge, this represents the state-of-the-art for GaN VCOs in terms of frequency, output power, and phase noise performance. This work demonstrates the potential for the use of GaN technology for high frequency, high power, and low phase noise frequency sources for military and commercial applications

A high-Q sapphire loaded superconducting cavity resonator

Describes the microwave properties of a sapphire loaded superconducting cavity resonator. The authors report measurements of energy confinement, evanescent field scale lengths and radiation losses. They report high quality factors, in excess of 109 at cryogenic temperatures, for a resonator based on a sapphire element mounted inside a superconducting cavity. From the measured properties we show that resonators of this type have potentially valuable applications as ultra-high-stability oscillators, high-Q filters and as low phase noise frequency sources.

High<tex>Q</tex>sapphire loaded superconducting cavities and application to ultrastable clocks

This paper describes the microwave properties of a sapphire loaded super conducting cavity resonator. We report measurements of energy confinement, evanescent field scale lengths, and radiation losses. We report high quality factors, in excess of 109at cryogenic temperatures, for a resonator based on a sapphire element mounted inside a superconducting cavity. Resonators of this type have potentially valuable applications as ultrahigh stability oscillators, high Q filters and as low phase noise frequency sources.