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Is it necessary to match an antenna to free space impedance?

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magnetra

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Matching

Its known that free space has characteristic impedance of 377Ω. So don't we need to match our antenna to the impedance of free space?

Magnetra
 

vfone

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Re: Matching

Okay.
So…one end of the matching circuit will be connected to the antenna…and the other end where? :)
Antenna itself by definition is a kind of matching circuit between free-space and the radio.
 

flatulent

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Re: Matching

There are two different things involved. The free space impedance is the ratio of the electric and magnetic field strengths. The antenna impedance is the ratio of voltage and current at the feed point.
 

arunkumar

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Re: Matching

Which impedance of the antenna you want to be 377Ω? At the input or at the surface/edge from where the waves actually radiate into free space??

If you do at the input, then you have to design the circuit's output impedance to be 377Ω. Even if you use a cable in between then it should also be designed for 377Ω. Even if you do everything it won't help as the impedance at the feed has got nothing to do with the free space impedance.

Do you think it's possible to make the radiating edge alone to be 377Ω?

Moreover, antenna by definition is a matching circuit that bridges the gap between the electronic circuit and the free space.
 

magnetra

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Matching

Well, with the discussion above, I can conclude that my idea was a lame one. I get the concept. Thanks for the discussion.

Regards
Magnetra
 

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