Utilizing multi-point temperature sensing to evaluate the low frequency noise of phasemeter for intersatellite laser...

Area of Science:

• Physics
• Astronomy
• Engineering

Background:

• High-precision phasemeters are crucial for intersatellite laser interferometers detecting gravitational waves (GWs).
• Meeting the demanding bandwidth (5-25 MHz) and resolution (μrad/Hz at mHz) requirements poses significant electronic signal processing challenges.

Purpose of the Study:

• To investigate the primary noise source in the low-frequency band of phasemeters.
• To develop and evaluate a method for assessing thermal drift noise in phasemeters.

Main Methods:

• Established a mathematical model linking thermal drift to phase noise.
• Proposed and implemented a multi-point temperature sensing scheme for critical electronic components.
• Evaluated a commercial phasemeter platform using the developed model and sensing scheme.

Main Results:

• Identified thermal drift noise as the dominant noise source for phasemeters between 0.1 and 1 mHz.
• Demonstrated the significant impact of temperature linear drift and component overcorrection on phase noise.
• Validated the proposed mathematical model and temperature sensing scheme.

Conclusions:

• Thermal drift is the primary limiting factor for phasemeter performance at low frequencies.
• The proposed multi-point temperature sensing scheme offers a universal solution for evaluating temperature effects in electronic circuits.
• This work provides a pathway for improving the sensitivity of future gravitational wave observatories.