I have the following problem: the radiation pattern of an antenna is measured in an anechoic chamber at a certain frequency and the gain is read by a VNA (path loss, cable loss ant receiving antenna gain are removed in the post-processing software). If I have the gain at different (theta,phi) angles, how can I compute the efficiency of that antenna.
Thank you!
I know the transmitting power (is 0 dBm), and I have s21 (in dB) - this is my antenna gain. If I integrate it (I did the average over all phi*theta angles) I obtain an avarage gain. This would mean that the efficiency if equal to the average gain of the antenna which I don't know if it is correct...
Average in linear numbers, not dB.
If H and V is measured in an anechoic environment is gain for a small antenna in each measured direction: √(H²+V²).
Integration of gain for full sphere gives total radiated power.
Abs. ant.eff. %= (Radiated power*100)/(Tx power-Reflected power)
Realized ant.eff. is less as there always are losses due to reflections.