Hugo wrote at 2009-05-13 14:20:20
Dear Luis, I have something to add or at least for you to clarify me.
OFD = EIRP + G1m2 - Losses (1) and The gain of a reference 1m2 antenna is the tool used to convert from a flux density to effective power captured per m2, G1m2 = 10Log10(4PI) + 20LOG(F/c)=43,8 (2).
My questions/remarks, the antenna Gain formula you mentioned isn't considering efficiency aspects?
Also and more critical,
the POwer Flux Density (S) can be given by:
S (dBW/m^2)= PT x GT /(4*pi*d^2) where PT and GT are related with transmission EIRP, d is distance from the center of the antenna up to the spherical distance d in meters.
Arranging the formula you can get:
S = EIRP - 20 log d - 11 or
EIRP = S + 20logd + 11.
What I find strange in this EIRP calculation from one Power Flux density is that is not considering other variables from Friis Free Space loss formula like frequency.
Using both approaches we have completely differente values of required dish and amplifier sizes...so what is the correct approach?
Thanks in advance
ld wrote at 2015-07-29 14:01:57
check this: page 8, http://dsp-book.narod.ru/SolManComm/haykin8.pdf