Broadband Matching With
Short (<1/4 Wave) LinesLINC2 features a new matching tool that employs ¼ wave stepped impedance transformers to affect a broadband match between any two real or complex impedances.
One problem with using cascaded ¼ wave transformers (as demonstrated in DEMO 3) is the accumulated length of the lines. 50 ohm quarter wave microstrip lines on 32 mil Rogers 4003 have lengths of 1.8 inches (1800 mils) each at 1000 MHz. The 3-section transformer in DEMO 3 would have a total length of close to 5.4 inches!
LINC2 features a new matching tool that employs short (<¼ wave) stepped impedance transformers to affect a broadband match between any two real or complex impedances. The length of the transmission lines used can be continuously adjusted from a maximum electrical length of 90° down to a minimum length determined by the program.
The design tool is directly linked to the schematic window so that "live" schematics are automatically generated by clicking the "Schematic" button at the bottom of the screen.
The following example demonstrates how to use the LINC2 Impedance Matching tool to match 50 ohms to 10+J1.5 ohms over a 25% bandwidth centered at 1 GHz using short transmission lines. The LINC2 synthesis tool will be used to shorten the lines to nearly 50% of their maximum length.
Click here to see the step by step procedure using LINC2.