On Mon, 21 Nov 2016 08:22:50 -0800 jimlux <jim...@earthlink.net> wrote:
> I'm not sure about whether an anechoic (which is really "hypoechoic") > chamber is going to get you the data you need. Calibrating the chamber > to the needed level of accuracy might be harder than doing field > measurements. [...] > sin(2 degrees) is 0.034, or -30dB. So a spurious reflection that is 3 > cm different path length (modulo wavelength) and 30 dB down will give > you a 1mm phase center error. 0.1 mm is -50dB. Interesting. I haven't done the math, so I didn't think about that. Yes, the reflections in the chamber would probably limit the resolution. Now I wonder how the calibration data for mass produced geodetic antenna are collected. I very much doubt they put them outside for a couple of days to measure them exactly. Attila Kinali -- Malek's Law: Any simple idea will be worded in the most complicated way. _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.