RF Electronics Chapter4: Transmission Line Transformers and Hybrids Page 81
2022, C. J. Kikkert, James Cook University, ISBN 978-0-6486803-9-0.
coupled port, the bottom right port 3. The remainder appears at the main output port 2
and no power appears at the isolated port 4. For a 3 dB coupler in a 50 system, lines
TL1 and TL4 have an impedance of 50/2 and lines TL2 and TL3 have an impedance
of 50 . A Microstrip PCB layout is shown in figure 4.27. The resistive losses of a
Branchline coupler are less than that of a 1.5 Rat-race hybrid.
Figure 4.26. Branchline coupler circuit.
Figure 4.27. Branchline coupler PCB layout.
Figure 4.28. Branchline Coupler analysis.
RF Electronics: Design and Simulation
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