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ISRO Scientist EC 2014 Official Paper

Option 2 : All diagonal elements will be zero.

CT 3: Building Materials

3014

10 Questions
20 Marks
12 Mins

In the S matrix, the self terms (diagonal elements of the scattering matrix) are the reflection coefficients (quantities used to determine the amount of the incident signal reflected back into the originating port) associated with each port, and the off-diagonal terms are the transmission coefficients. when all ports are matched then the reflection coefficient will be zero i.e. all diagonal elements will be zero.

__Important Points__

**Scattering Matrix-** It is a square matrix that gives all the combinations of power relationships between the various input and output ports of a Microwave junction. The elements of this matrix are called "Scattering Coefficients" or "Scattering S Parameters".

**Properties of [S] Matrix-**

1. [S] is always a square matrix of order n × n

[S]_{n×n}

2. [S] is a symmetric matrix

i.e., S_{ij} = S_{ji}

3. [S] is a unitary matrix

i.e., [S][S]^{∗ }= I