Topic: Electromagnetics
Scattering Matrix for a microwave network, which is matched at all the ports, will satisfy the following condition
- A. All non-diagonal elements will be zero
- B. All diagonal elements will be zero
- C. None of the matrix elements will be zero
- D. All the matrix elements will be zero
Answer: B. All diagonal elements will be zero
Explanation: For a microwave network that is perfectly matched at all its ports, there are no reflections at any port when the other ports are terminated in matched loads. This implies that the reflection coefficients (the diagonal elements $S_{ii}$ of the scattering matrix) are all zero.