Branch line

Open branch line (stub)

As a stub in is high-frequency systems a electric line for impedance matching , ie to improve the insertion loss or reduction of the reflected wave, respectively.

The branch line can be open at the end ( open circuit ) or short-circuited (short circuit).

In the Smith diagram it causes a rotation of the impedance or admittance point : open cable end to the right, short-circuited to the left.

The length of the branch line in relation to the specific wavelength in the medium determines “how far” this rotation takes place. ${\displaystyle \lambda }$

The English word "stub" has meanwhile entered the German language as "stub" .

See also

• Line theory
• Network analyzer
• Quadrupole parameters

literature

• Heinrich-Karl Podszeck: Carrier-frequency message transmission over high-voltage lines. Third completely revised edition, Springer Verlag Berlin, Berlin 1962.
• Otto Zinke , Heinrich Brunswig: Textbook of high frequency technology. First volume, fourth, revised and expanded edition, Springer Verlag Berlin - Heidelberg GmbH, Berlin 1990, ISBN 978-3-540-51421-3 .

Web links

• Adjustment (accessed October 12, 2015)
• Introduction to high frequency technology (accessed October 12, 2015)