Difference between revisions of "S-Parameters"

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(Created page with "=Scattering parameters= S-parameters (or scattering parameters) are used to describe how energy can propagate through an electric network.</br>S-Parameters are used to descri...")
 
 
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=Scattering parameters=
 
=Scattering parameters=
  
S-parameters (or scattering parameters) are used to describe how energy can propagate through an electric network.</br>S-Parameters are used to describe the relationship between different ports, when it becomes especially important to describe a network in terms of amplitude and phase versus frequencies, rather than voltages and currents(3).</br></br>The image(3) seen below illustrates this for a 2 port system,
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S-parameters (or scattering parameters) are used to describe how energy can propagate through an electric network.</br>S-Parameters are used to describe the relationship between different ports, when it becomes especially important to describe a network in terms of amplitude and phase versus frequencies, rather than voltages and currents(1).</br></br>The image(3) seen below illustrates this for a 2 port system,
  
 
[[File:ScatteringParameters.png]]
 
[[File:ScatteringParameters.png]]
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==Sources==
 
==Sources==
(1)https://www.everythingrf.com/community/what-are-s-parameters</br>
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(1)https://www.everythingrf.com/community/what-are-s-parameters - Andreas Henkel, Aug 6, 2019 </br>
(2)https://www.rfpage.com/s-parameters-in-rf-testing-simple-explanation</br>
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(2)https://www.rfpage.com/s-parameters-in-rf-testing-simple-explanation - March 19, 2016, Rajiv</br>
(3)http://literature.cdn.keysight.com/litweb/pdf/5991-3736EN.pdf</br>
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(3)http://literature.cdn.keysight.com/litweb/pdf/5991-3736EN.pdf - Keysight Technologies, 2018, Published in USA, June 18, 2019, 5991-3736EN</br>
 
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Latest revision as of 15:54, 21 April 2020

Scattering parameters

S-parameters (or scattering parameters) are used to describe how energy can propagate through an electric network.
S-Parameters are used to describe the relationship between different ports, when it becomes especially important to describe a network in terms of amplitude and phase versus frequencies, rather than voltages and currents(1).

The image(3) seen below illustrates this for a 2 port system,

ScatteringParameters.png

For example an set of S-Parameter tests on a 2 port DUT:
S11 – Reflection coefficient at port 1. A signal sent from port one of VNA and received at port one
S12 – Reverse transmission (gain/loss). Signal sent from port 2 of VNA and received at port 1
S21 – Forward transmission (gain/loss). Signal sent from port one of VNA and received at port 2
S22 – Reflection coefficient at port2. Signal sent from port 2 of VNA and received at port 2.

As an example the following image(2) shows an S21 insertion loss measurement performed on a bandpass filter.

S21InsertLossExample.png

Devices with more than two ports

If the number of ports in a network increases, the s-parameter will become complex according to the number of ports.
Two port network has four parameters, three port will have nine parameter and so on.
The parameters of any given s-matrix are represented as Snn where S is the parameter and n is the number or port.

This is illustrated on the image(2) down below.

ScatteringParametersMultiplePorts.png



Sources

(1)https://www.everythingrf.com/community/what-are-s-parameters - Andreas Henkel, Aug 6, 2019
(2)https://www.rfpage.com/s-parameters-in-rf-testing-simple-explanation - March 19, 2016, Rajiv
(3)http://literature.cdn.keysight.com/litweb/pdf/5991-3736EN.pdf - Keysight Technologies, 2018, Published in USA, June 18, 2019, 5991-3736EN