Week 11
Branch-Line Hybrids
I revisit transmission lines through Wilkinson and branch-line networks using my assignments, Cadence circuits, and S-parameter figures.
What I connect in this unit
A branch-line hybrid uses four quarter-wave branches to divide an input between through and coupled ports with an approximately ninety-degree phase difference. Four-port symmetry controls amplitude balance, and the remaining port should be isolated.
Concept map
- Ninety-degree phase difference
- Four-port network
- Coupled and isolated ports
- Amplitude balance
Technical anchor
Plot magnitude and phase of both transmission paths at the design frequency and compute Δφ=unwrap(angle Scoupled-angle Sthrough). Read the isolated-port S-parameter at the same marker.
How I review it
First reconcile physical port placement with S-parameter indices, then evaluate amplitude imbalance, phase error, and isolation as separate quantities.
Connection to the full course
Unit 11 of 12. Unit numbers arrange the saved assignments and circuits by concept flow rather than attendance weeks.