When two 2-port networks are connected in series, the primary parameters you need to calculate are:
1. **Overall Impedance (Z-parameter)**
2. **Overall Admittance (Y-parameter)**
3. **Overall Hybrid (H-parameter)**
4. **Overall Transmission (ABCD-parameter)**
Here's a breakdown of how to calculate each set of parameters:
### 1. Overall Impedance (Z-parameters)
For two networks with Z-parameters \( Z_1 \) and \( Z_2 \), the overall impedance parameters \( Z_{total} \) can be calculated as:
\[ Z_{total} = \begin{bmatrix}
Z_{11} & Z_{12} \\
Z_{21} & Z_{22}
\end{bmatrix} \]
Since the networks are in series, you add the impedances of each network:
\[ Z_{total} = Z_1 + Z_2 \]
### 2. Overall Admittance (Y-parameters)
For two networks with Y-parameters \( Y_1 \) and \( Y_2 \), the overall admittance parameters \( Y_{total} \) are:
\[ Y_{total} = Y_1 + Y_2 \]
However, if the networks are connected in series, you need to convert the Z-parameters to Y-parameters for each network first, then add them.
### 3. Overall Hybrid (H-parameters)
For H-parameters, if you have \( H_1 \) and \( H_2 \), the overall hybrid parameters \( H_{total} \) can be calculated as:
\[ H_{total} = \text{H}_1 + \text{H}_2 \]
Like with Y-parameters, conversion might be required if you are adding parameters from different network representations.
### 4. Overall Transmission (ABCD-parameters)
For two networks with ABCD parameters \( A_1, B_1, C_1, D_1 \) and \( A_2, B_2, C_2, D_2 \), the overall transmission parameters \( A_{total}, B_{total}, C_{total}, D_{total} \) are found by:
\[ \begin{bmatrix}
A_{total} & B_{total} \\
C_{total} & D_{total}
\end{bmatrix} = \begin{bmatrix}
A_1 & B_1 \\
C_1 & D_1
\end{bmatrix} \cdot \begin{bmatrix}
A_2 & B_2 \\
C_2 & D_2
\end{bmatrix} \]
### Summary
In essence, when two 2-port networks are connected in series, you need to:
1. **Calculate** the equivalent impedance, admittance, hybrid, and transmission parameters for the entire series connection.
2. **Convert** between different parameter representations as needed based on the type of calculation you are performing.
Each method requires accurate addition or multiplication of parameters based on the network's connection configuration.