The first two are for a medium or a wave itself.
The third is of a transmission line.
The fourth is the thevenin equivalent impedance of a part of the circuit
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Amr Ali www.embedded-tips.blogspot.com
Wave impedance is the ratio between electric fields and magnetic fields of a propagating wave. Intrinsic impedance is the impedance of the medium that the wave propagates in. It is a characteristic of the medium. The wave impedance is equal to the intrinsic impedance.
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Amr Ali www.embedded-tips.blogspot.com
Wave impedance is the ratio between electric fields and magnetic fields of a propagating wave. Intrinsic impedance is the impedance of the medium that the wave propagates in. It is a characteristic of the medium. The wave impedance is equal to the intrinsic impedance.
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Amr Ali www.embedded-tips.blogspot.com
The wave impedance is equal to the intrinsic impedance of the medium only when "For a transverse-electric-magnetic (TEM) plane wave travelling through a homogeneous medium, the wave impedance is everywhere equal to the intrinsic impedance of the medium." Source Wikipedia.
free space is a homogeneous medium that's why we have intrinsic & wave impedance are same
I saw many wrong replays here (For example: wave and intrinsic impedance have same value only in TEM mode). Stick on what is mentioned in genuine references like Pozar book. I have just checked wikipedia.org and it seemed authentic.