Influence of Noise on Scattering-Parameter Measurements

Area of Science:

• Electrical Engineering
• Metrology
• Signal Processing

Background:

• Scattering-parameter (S-parameter) measurements are crucial for characterizing electronic components.
• Vector network analyzers (VNAs) are standard instruments for S-parameter measurements.
• Understanding and quantifying measurement noise is essential for accurate results.

Purpose of the Study:

• To present a general model for noisy S-parameter measurements using a VNA.
• To statistically analyze the residual error introduced by noise in S-parameter measurements.
• To validate the proposed noise model through experimental data.

Main Methods:

• Development of a general mathematical model for noisy S-parameter measurements.
• Statistical analysis of the residual error, treating it as a complex Gaussian quotient.
• Derivation and discussion of relevant statistical quantities.
• Experimental validation using a two-port VNA.

Main Results:

• The residual error in S-parameter measurements due to noise can be modeled as a complex Gaussian quotient.
• Statistical quantities characterizing the noise influence were derived.
• Experimental results validated the proposed noise model.
• Noise-induced uncertainty is often critical, particularly for small-magnitude S-parameters.

Conclusions:

• The developed model accurately describes noise in VNA S-parameter measurements.
• Statistical analysis provides a framework for understanding noise impact.
• Accurate characterization of noise is vital for reliable S-parameter data, especially in sensitive applications.