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# gammaout

Calculate output reflection coefficient of two-port network

## Syntax

``coefficient = gammaout(s_params,z0,zs)``
``coefficient = gammaout(hs,zs)``

## Description

example

````coefficient = gammaout(s_params,z0,zs)` calculates the output reflection coefficient of a two-port network. `z0` is the reference impedance Z0; its default value is 50 ohms. `zs` is the source impedance Zs; its default value is also 50 ohms. `coefficient` is an M-element complex vector.```

example

````coefficient = gammaout(hs,zs)` calculates the output reflection coefficient of the two-port network represented by the S-parameter object `hs`.```

## Examples

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Calculate the output reflection coefficient using network data from a file.

```ckt = read(rfckt.amplifier,'default.s2p'); s_params = ckt.NetworkData.Data; z0 = ckt.NetworkData.Z0; zs = 100; coefficient = gammaout(s_params,z0,zs)```
```coefficient = 191×1 complex -0.0741 - 0.3216i -0.0765 - 0.3184i -0.0787 - 0.3152i -0.0809 - 0.3121i -0.0829 - 0.3090i -0.0848 - 0.3059i -0.0867 - 0.3029i -0.0884 - 0.3000i -0.0900 - 0.2971i -0.0915 - 0.2943i ⋮ ```

Define a S-parameters object from a file.

`s_params = sparameters('default.s2p');`

Specify the source impedance.

`zs = 100;`

Calculate the output reflection coefficient using the `gammaout` function. .

`coefficient = gammaout(s_params,zs)`
```coefficient = 191×1 complex -0.0741 - 0.3216i -0.0765 - 0.3184i -0.0787 - 0.3152i -0.0809 - 0.3121i -0.0829 - 0.3090i -0.0848 - 0.3059i -0.0867 - 0.3029i -0.0884 - 0.3000i -0.0900 - 0.2971i -0.0915 - 0.2943i ⋮ ```

## Input Arguments

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Two-port S-parameters, specified as a complex 2-by-2-by-M array. M is the number of two-port S-parameters.

Data Types: `double`

Reference impedance, specified as a positive scalar.

Data Types: `double`

Source impedance, specified as a positive scalar.

Data Types: `double`

Two-port network, specified as an S-parameter object.

Data Types: `function_handle`

## Output Arguments

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Output reflection coefficient, returned as a M element complex vector.

## Algorithms

The function calculates `coefficient` using the equation

`${\Gamma }_{out}={S}_{22}+\frac{{S}_{12}{S}_{21}{\Gamma }_{S}}{1-{S}_{11}{\Gamma }_{S}}$`

where

`${\Gamma }_{S}=\frac{{Z}_{s}-{Z}_{0}}{{Z}_{s}+{Z}_{0}}$`

## See Also

Introduced before R2006a

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