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arXiv · 2210.07080

Measuring Noise Parameters Using an Open, Short, Load, and 1/8-wavelength Cable as Source Impedances

Danny C. Price·Cheuk-Yu Edward Tong·Adrian T. Sutinjo·Lincoln J. Greenhill·Nipanjana Patra
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Abstract

Noise parameters are a set of four measurable quantities which determine the noise performance of a radio-frequency device under test. The noise parameters of a 2-port device can be extracted by connecting a set of 4 or more source impedances at the device's input, measuring the noise power of the device with each source connected, and then solving a matrix equation. However, sources with high reflection coefficients cannot be used due to a singularity that arises in entries of the matrix. Here, we detail a new method of noise parameter extraction using a singularity-free matrix that is compatible with high-reflection sources. We show that open, short, load and an open cable ("OSLC") can be used to extract noise parameters, and we detail a practical measurement approach. The OSLC approach is particularly well-suited for low-noise amplifier measurement at frequencies below 1 GHz, where alternative methods require physically large apparatus.

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Danny C. Price, Cheuk-Yu Edward Tong, Adrian T. Sutinjo, Lincoln J. Greenhill, Nipanjana Patra. 2022-10-13. Measuring Noise Parameters Using an Open, Short, Load, and 1/8-wavelength Cable as Source Impedances. https://doi.org/10.1109/tmtt.2022.3225317

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