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