Conference paper
Accurate Noise Figure Measurements for Highly Mismatched Preamplifiers
Center for Hyperpolarization in Magnetic Resonance, Centers, Technical University of Denmark1
Department of Electrical Engineering, Technical University of Denmark2
Center for Magnetic Resonance, Department of Electrical Engineering, Technical University of Denmark3
Electromagnetic Systems, Department of Electrical Engineering, Technical University of Denmark4
A method reducing the uncertainty of noise figure measurements of highly mismatched preamplifiers is presented. In many cases when measuring the noise figure of preamplifiers for MRI receive arrays the uncertainty is approximately ±0.4 dB. Since the noise figure of the preamplifier is also in this range, a more accurate method is needed.
Here we show an increase of 59 % in noise figure accuracy by adding an attenuator between the noise source and preamplifier.
| Language: | English |
|---|---|
| Year: | 2018 |
| Proceedings: | Joint Annual Meeting ISMRM-ESMRMB 2018 |
| Types: | Conference paper |
| ORCIDs: | Johansen, Daniel Højrup , Sánchez-Heredia, Juan D. , Zhurbenko, Vitaliy and Ardenkjær-Larsen, Jan Henrik |
