TABLE OF CONTENTS One of the common four-terminal two-port networks is the lattice, or bridge network, shownin Figure 10.26(a). Lattice networks are used infiltersections and are also used as attenuaters filter and attenuaters which we will discuss in Chapter 13. Lattice structures are sometimes used in preference to ladder structures in some special applications. Z a and Z d are called the series arms, Z b and Z c are called the diagonal arms. It can be observed that if Z d is zero, the lattice structure becomes a ?-section as shown in Figure 10.26(c). The lattice network is redrawn as a bridge network as shown in Figure 10.26(b).
Z-parameters,
When
Therefore
If the network is symmetric, then Z a = Z d, Z b = Z c
Therefore
When I2 = 0, V2 is the voltage across 2-2 ?
Substituting the value of V 1 from Equation (10.87), we have
Therefore
If the network is symmetric, Z a = Z d, Z b = Z c
When the input port is open, I 1 = 0,
The network can be redrawn as shown in Figure 10.27.
Substituting the value of V2 into Equation (10.88), we get
If the network is symmetric, Z a = Z d, Z b = Z c,
Therefore
From Equation (10.89), we have
If the network is symmetric, Z a = Z
