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UK
RFID-UHF-Antennas
17
9 Technical appendix
9.1 Antenna gain
The gain is the ratio between the radiated power density in the main radiation di-
rection for the antenna in question and a reference antenna with the same supply
power�
Reference antennas are isotropic radiators or λ/2 – dipole
Frequent logarithmic tasks:
- dBi: linear gain based on isotropic radiator
- dBd: linear gain based on dipole
- dBic: circular gain based on isotropic radiator