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PUBLICATIONS

Noise Characterization of Multiport Amplifiers

Published

Author(s)

James P. Randa

Abstract

I address the issue of the definition and measurement of noise figure and parameters to characterize multiport devices, particularly differential amplifiers. A parameterization in terms of the noise matrix appears to be the most practical. the noise figure for a given output port is defined and related to the noise matrix and scattering parameters of the device. Two examples are considered in detail: a 3-port differential amplifier and a 4-port mixed-mode amplifier, both with reflectionless terminations. The noise figures, effective input temperatures, and gains are related to the results of a series of hot-cold measurements, as in the familiar two-port case.
Citation
IEEE Transactions on Microwave Theory and Techniques
Volume
49
Issue
10
Pub Type
Journals

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Keywords

amplifier noise, differential amplifier, multiport amplifier, noise, noise figure, noise matrix, thermal noise
Advanced communications, Electronics, Electromagnetics and Semiconductors

Citation

Randa, J. (2001), Noise Characterization of Multiport Amplifiers, IEEE Transactions on Microwave Theory and Techniques, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=5219 (Accessed October 11, 2025)

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Created October 1, 2001, Updated January 27, 2020
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