Re: How to apply frequency-dependent Antenna Factor
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Yes, you could so long as you are at or below -30 dBm on the TinySA (I believe the spec is -26 dBm).? Add 107 you dBm to get dBuV.? Or more rigorously:
? ?? dBV = dBm + 10 lob[Z]?+ 90 ?
HOWEVER, the reg. testing requires you to search vertically in both vertical and horizontal polarizations for the maximum of at least 6 of the highest "quick-look" frequencies.? The "quick-0look" search should include measuring in both vertical and horizontal poilarizatioins at every 22.5-degrees of rotation of the DUT.
In addition, a good conductive "ground plane" (and it REALLY IS a GROUND PLANE - REFLECTIVE)? be present totally between the DUT and the antenna.? Without that, you can not make good regulatory judgement in a pre-compliance setup.
Dave - W?LEV?
Just a matter of spectral interpretation: Some time ago, I recognized that tinySA ultra offers a quasi peak display. But what I saw was something like attack and decay effects so to say over the time axis, or said in another way: along the frequency axis. But that's not quasi peak of a single frequency that's staying - let's say one second before the next frequency is swept up. But perhaps you'd get a reasonable result when the sweep is done as slowly as in standard tests.
Rob
On Tue, 04 Mar 2025 14:51:16 +0100, Magne Lauritzen via <mag.lauritzen= [email protected]> wrote: Good day,
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I would like to know whether I can apply the Antenna Factor (AF) for my calibrated biconical antenna to measurements being made by the TinySA Ultra. Antenna theory refresher: The AF is a value that lets you go from measured intensity to actual E-field intensity. It is critical when doing compliance testing of radiated emissions.
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If the AF was just a single value I could apply it to the TinySA settings as a pretend attenuator between the antenna and the TinySA. But the AF of my antenna is highly frequency-dependent, varying by over 20dB over my frequency range of interest.?
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