What measurements do you perform on an active antenna?

what measurements do you perform on an active antenna apart from radiation patterns, gain measurements to fully characterise its performance?

Hi , kelvchan
two other important parameters we consider them in antenna analysis, are input impedence and reflection from input port (for impedence matching ,SWR).


I hope it'll be helpful

hello,

what you request depends on the active antenna type you are designing. if it is a receive antenna w/o frequency conversion your measurement parameter must be G/T. If it is a transmit antenna your parameter is EIRP (DC efficiency, power related magnitudes as well). If it is an oscillating antenna you must also check the eirp, locking bandwidth,... if it is a frequency conversion antenna you must check the conversion efficiency,....

In summary tha antenna and its active part are linked, and you must characterise the active antenna thinking on its functionality.

Hope it helps

rgdz

Hi,
it's an active antenna (receive only) and you want to know what to measure. That is divided into two parts. The first is the radiation patter which includes the antenna element and the amplifier unit. You then have the pattern and can evaluate a gain regarding a reference antenna, such as λ/4 antenna.
The second part is only to describe the amplifier. Here you measure the S-parameters. Important is to know the input and output impedance. The input impedance is often very high if you use a FET amplifier. That will be in general good if it is a broadband antenna. You then measure the noise from the amplifier. That is often done by 50Ω input impedance, even if that does not apply if it is connceted with the antenna.
If that antenna has also an AGC (automatic gain control) built in, then you have to measure the values when it starts to decrese the gain and how much it can decrese. It should be able to attenuate up to 40dB.
Well, thats all for now. If you want to know more, specify your problem more exactly like what kind of antenna it is.
For more questions use: elomatic@gmx.ch

ciao, Bodo

Hi
I am new in active antenna area so i need help. now i am intending to simulate an oscillator antenna but i can't get good results anyone who has a project in ADs od such example please don't hesitate to send it to me

Hi Helio, I think that's very important consider Polarization Diagram too.