Microstrip Branchline Coupler
Above: This example shows a microstrip branchline coupler on alumina (er = 9.8) material with a thickness of 25 mils. Analysis also includes a shielded enclosure with metal lid 100 mils above the surface of the alumina substrate.
View of the circuit in Sonnet Lite project editor. Port de-embedding is referenced to the ends of the four microstrip lines on the substrate edge.
Surface current density (Jxy) on the microstrip filter at 4.8 GHz, near the frequency of optimum performance. Red indicates high current density, blue is low. Current density shown is displayed by the current density viewer in Sonnet Lite.
Below: Simulated S-parameter response by Sonnet Lite. Input return loss (S11) is shown in the red graph, isolation between ports 1 and 4 (S14) is shown in black, and the balanced quadrature ports (S21 and S31) are shown in blue and magenta. Analysis results are for lossless metal inside a metal shielded enclosure (no radiation loss).
This analysis required 6 Mbytes at the highest frequency of 5.5 GHz. This simulation may be performed using the Registered version of Sonnet® Lite. All results and graphics shown were created using Sonnet Lite.
