Starting RF Study: Wavelength and Electrical Length
I started by asking why RF is more than a label for high frequency. When physical size is no longer negligible relative to wavelength, phase and reflection must be tracked along position.
RF · Microwave Series
RF Foundations Revisited with RFDH
A study path from wavelength and electrical length through 50 ohms, transmission lines, reflection, S-parameters, and decibels.
Reading 50 Ohms, Ports, and Matching as One Flow
Memorizing 50 ohms, ports, and matching separately made S-parameter setups confusing. I drew the source-line-load reference planes first and connected all three terms on one path.
Comparing Transmission Lines, Microstrip, CPW, Coax, and Waveguide
Instead of listing line names, I compared each structure by return path, field confinement, mode, and fabrication variables.
Converting Reflection Coefficient, Return Loss, and VSWR
I rewrote the conversion order so that sign conventions and ratios are not mixed when one mismatch is expressed three ways.
Reading the S-Parameter Matrix and VNA Screens
I relabeled S11, S21, S31, and S23 by excitation and observation ports rather than treating them as curve names.
Checking dB and dBm Calculations by Hand
I write the reference and unit first to avoid mixing a dB ratio with absolute dBm power.