Network Analysis and Synthesis, 1st Edition by Pearson

490 Network Analysis and Synthesis

Now, substituting the value of I

1

in equation (11.71), the equation can be written as in the

following:

V

1

= I

1

(2)

=

6

17

2

2

I

()

=

12

17

2

I

or

Y

I

V

V

21

2

1

1

0

17

12

=

=

=

Example 11.12 For the symmetrical two-port

network shown in Figure 11.28, find the Z-parameters

and A, B, C and D parameters.

Solution: Using KVL for loops, we get the equation

as follows:

VI II

11

12

30 40

=+ +()

or

VI

I

11

2

70 40

=+

(11.72)

and

VI

II

II

22

12

12

30 40

40 70

=+ +

=+

()

(11.73)

Let us find the Z-parameters

Case I: When I

2

= 0 from equations (11.72) and (11.73), we get the following:

VI

VI

11

21

70 40

==

and

or

I

V

1

1

70

=

∴=

=

=













=Ω

Z

V

I

I

V

V

11

1

1

2

1

1

0

70

70

Z

V

I

I

I

I

21

2

1

2

1

1

0

40

40=

=

== ...