what's the maximum interfere level at antanna in air
Is there anybody knows the exact value of them?
no idea......sorry
Antenna is not problem - bud LNA in first step in reciver is a different case...
Most LNA in consumer equipment begins to puke around -40 - -30 dBm and make intermodulation in strong multicarrier enviroment.
GSM need least 9 dB signal over interfrence margin to recive readable data - more advanced modulation as EDGE, CDMA needs much more signal to interference margin ie. higher data density per symbol. Look in standards for above technology if you want detailed information.
The signal level around an antenna can vary greatly and looking for some maximum level from the literature is probably not useful.
I would start by evaluation the site where you plan to operate and then try to identify strong, nearby transmitters in your band of interest. If you are in a dense urban area the levels will be much higher than if you are in the countryside or sheltered in some way. The one way Radar Range Equation might be helpful. Look for the discussion in Skolnick among other good references.
You might also consider doing a survey with a spectrum analyzer to see what you see near your site.
All of the maximum antenna values are in the relevant specifications. Start poking around www.3gpp.com and 3gpp2.com for the specs. You are looking for Receiver blocking performance.
Dave