RF cat corner
Nonlinear impedance (draft)
A comprehensive analysis of nonlinear impedance effects in power amplifiers, including transistor output impedance behavior and gain compression.
New co-authors
At the beginning, this site had one author, Hadrien Theveneau F4INX. Since some coauthors are now contributing on a more or less regular basis, I...
The fine art of (not) doing oscillators
Practical insights and common pitfalls in oscillator circuit design, with real-world examples and solutions.
A (not so) gentle introduction to operational amplifiers.
A comprehensive guide to understanding operational amplifiers, their characteristics, configurations, and practical applications in analog circuits.
Hilbert transform demo.
The discrete Hilbert transform seems rather mysterious. However, the principle as well as his mathematics are not so complicated: the Hilbert transform is mainly a...
LC ladder impedance matching.
2025-12-21: Replace statically generated plots by dynamically generated and interactive plots using plotly.js. Note the javascript code is also for you: if you need to...
On stability of capacitive loaded op-amps.
Introduction
IQ modulator and quadrature coupler sign issues.
Update from 2024-11-05: Steve from Microwaves 101 also tackled this topic (https://www.microwaves101.com/encyclopedias/branchline-coupler-port-definition), proposing a different port-naming convention for the branchline coupler. Steve names the direct...
Microstrip formulas comparison.
Introduction
MLCC voltage dependence.
This content was originally published on Microwaves 101 (https://www.microwaves101.com/encyclopedias/capacitor-voltage-effects). Many thanks to Steve for improvements on the original version. Have a look on his website...
Export QGIS maps and terrain height data to Forsk Atoll.
Forsk Atoll antenna planning software is not so hard to use when a suitable map and terrain height data is available for import into Atoll....
On group delay of antennas.
Many thanks, in the order of appearance in the LinkedIn discussion, to Dr. Pierre-Antoine Garcia, Theunis Beukman, Benoit Derat, Hüseyin Yiğit, Andreas Barchanski for the...
Design of a coaxial power combiner with low-impedance inputs and increased isolation.
Hadrien Theveneau, Christophe Gaquière, Romain Lenglet, Matthieu Werquin, Jean-Christophe Joly, and Stéphane Tortel
Transfer S parameters.
This content was originally published on Microwaves 101 (https://www.microwaves101.com/encyclopedias/transfer-s-parameters). Many thanks to Steve for hosting the original version. Have a look on his website for...
RFID coils should not be grounded.
Putting a solid ground plane in a PCB is a good practice. This allows to have good interconnexions between the different grounds of the components,...
Miller effect and solutions.
This content was originally published on Microwaves 101 (https://www.microwaves101.com/encyclopedias/miller-effect). Many thanks to Steve for improvements on the original version. Have a look on his website...
Why RFID antennas should not be called antennas ?
A friend of mine told me that he was looking for an “expert antenna engineer” to design RFID antennas, but he was not sure he...