Antenna for field measure at 3.5Ghz - RF Cafe Forums

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MR.D.
Post subject: Antenna for field measure at 3.5Ghz
Posted: Tue Jul 11, 2006 7:24 am
 
Lieutenant

Joined: Wed Nov 30, 2005 8:22 am
Posts: 2
Hello,
i need to realize some indoor/outdoor measure at 3.5Ghz.
For realize this measure is necessary a nonperturbative, x-y-z axis Rx antenna.
My idea is realize a narrow band measure with spectrum-analyzer, so a large-band probe for EMC measure is not good.
I don't find any antenna with this characteristic.
Build it is not too easy!!
Could anyone help me??
MR.D.
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nubbage
Post subject: Antenna for Field Measure at 3.5G
Posted: Tue Jul 11, 2006 12:40 pm
 
General
User avatar

Joined: Fri Feb 17, 2006 12:07 pm
Posts: 218
Location: London UK
The least perturbing narrow band antenna is probably a quater-wave groundplane or quarterwave sleeve balun type.

The length is about 2.1 cm at 3.5GHz, the horizontal H plane radiation pattern is omni and the E plane pattern is fairly broad. Just strip back 2.1 cm of semi-rigid coax, and add a small ground plane of radial wires to the solid outer at right-angles to the center conductor

Calibrating the gain accurately might be a problem, although there is probably now enough field experience of ground-plane antenna gain that you could find enough references on the web



Posted  11/12/2012