# For an ABCD parameter of a transmission line, which of the following is correct?

For an ABCD parameter of a transmission line, which of the following is correct?

### Right Answer is:

AD − BC = 1

#### SOLUTION

ABCD parameters are also known as transmission line parameters.

We know that the ABCD parameter of the transmission line

$\left[ {\begin{array}{*{20}{c}} {{V_1}}\\ {{I_1}} \end{array}} \right] = \left[ {\begin{array}{*{20}{c}} A&B\\ C&D \end{array}} \right]\left[ {\begin{array}{*{20}{c}} {{V_2}}\\ { – {I_2}} \end{array}} \right]$

The symmetry condition for a two-port network in terms of transmission parameters is: A = D

The Reciprocity condition for a two-port in terms of transmission parameters is **AD – BC = 1**