Journal article
Association and Dissociation of Optimal Noise and Input Impedance for Low-Noise Amplifiers
Department of Electrical Engineering, Technical University of Denmark1
Center for Magnetic Resonance, Department of Electrical Engineering, Technical University of Denmark2
Electromagnetic Systems, Department of Electrical Engineering, Technical University of Denmark3
Center for Hyperpolarization in Magnetic Resonance, Centers, Technical University of Denmark4
For magnetic resonance imaging (MRI) receive coil arrays, an ideal low-noise amplifier (LNA) is noise matched while exhibiting a high-input reflection coefficient of unity or slightly higher. For this purpose, we present a design approach allowing to manipulate the optimal noise impedance and input impedance.
The method is based on noise and S-parameters, hence technology independent. As an example, the method is used to design an LNA for MRI receive coil arrays operating at 32.1 MHz. The design demonstrates the highest coil decoupling published so far of 54 dB. The measured noise figure of 0.44 dB is also better than other published designs.
The measured gain is 22 dB with a 1-dB compression point of -14.5 dBm. The power consumption is 81 mW. We expect this method to enable better MRI receive coil array designs resulting in lower examination time and cost due to higher quality images.
| Language: | English |
|---|---|
| Publisher: | IEEE |
| Year: | 2018 |
| Pages: | 5290-5299 |
| ISSN: | 15579670 and 00189480 |
| Types: | Journal article |
| DOI: | 10.1109/TMTT.2018.2869603 |
| ORCIDs: | Johansen, Daniel Højrup , Sanchez-Heredia, Juan D. , Zhurbenko, Vitaliy and Ardenkjær-Larsen, Jan Henrik |
Biomedical imaging Design methodology Gain Impedance matching Low-noise amplifiers (LNAs) Magnetic resonance Noise figure Optimized circuit design Scattering parameters
CMOS integrated circuits Impedance MRI Magnetic resonance imaging Optimized production technology Radio frequency Transistors biomedical MRI coil array designs coil arrays coils design methodology gain impedance matching input impedance low noise amplifiers low-noise amplifier low-noise amplifiers (LNAs) magnetic resonance magnetic resonance imaging noise figure optimal noise impedance optimized circuit design scattering parameters
