HI GUYS,
I have read that in a transmission line if the line impedance is not equal to the load impedance reflections take place?
What is the exact reason for those reflections?

 

Hello,

Impedance matching is important to get all the power from the source in the load.
If there is a mismatch power can be reflected, this can lead to a malfunctioning of the source as it wants to put more power out.
Another effect can be that the transmission line starts to radiate some of the power, wich can lead to disturbances in the surrounding.

Here is a piece of text from agilent:
Impedance matching is required in order to optimize the power delivered to the load from the source.
Impedance matching is accomplished by inserting matching networks into a circuit between the source and the load.
Source: http://contact.tm.agilent.com/Agilent/tmo/an-95-1/classes/imatch.html

More information on transmission lines can be found here, in the links:
http://www.educypedia.be/electronics/electroniccalculatorstrans.htm

Greetings,
Bertus

 

may help

http://info.ee.surrey.ac.uk/Teaching/Courses/EFT/transmission/html/ReflectionsOnLines.html

 

This article became a classic in 1956. Nothing since has been written better on the subject.

Eric