50Ω antenna - RF Cafe Forums

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Mr. Enno
 Post subject: 50Ω antenna
Posted: Tue Apr 05, 2005 10:27 am 
Hi everyone!

I need a small and flexible antenna for a transceiver chip in the 868Mhz frequency band.

I've got a PCB layout, with single ended connection to 50Ω antenna.

Is it possible to use a 1/4λ coax-cable (50Ω) as antenna?

Hopefully anyone can give me an answer.

Enno.
 
  
 
Mr. Enno
 Post subject:
Posted: Wed Apr 06, 2005 8:11 am 
I've got the answer..
 
  
 
Kirt Blattenberger
 Post subject:
Posted: Wed Apr 06, 2005 8:23 am 
 
Site Admin
User avatar

Joined: Sun Aug 03, 2003 2:02 pm

Posts: 308

Location: Erie, PA

Greetings Mr. Enno:

So, what is your answer?

My guess is that the coax cable cannot be used as an antenna, although I have had a number of times when my cables were so trashy that they leaked enough to radiate rather well. With a well-constructed coaxial cable, the fields are all contained within the cable cross-section and should not radiate at all.

BTW, I deleted the duplicate original post since it appears to have been a mistake.

- Kirt Blattenberger :smt024
 
   
 
Mr. Enno
 Post subject:
Posted: Fri Apr 08, 2005 6:12 am 
I don't no, what will happen if you use an coax-cable for antenna. Perhaps there will be some radiation, but I think it isn't much.

I only know that a coax-cable mainly be used to connect the print to the antenna and not to replace an antenna.

Enno.

Posted  11/12/2012