Gain is most important thing in wireless communication and if its passive then it will be very useful here I write about antenna gain and diversity gain definition and its effect.
Antenna Gains
Mobile Station Antenna
- Portable mobile phones antennas have typically gain of 0 to 1 dBd.
- Car mounted antenna has a typical gain of 1 to 3 dBd.
Base Station Antenna
- Omni directional antennas typically have a gain of 0-9dBd.
- Directional antennas typically have a gain of 9 to 14 dBd.
Diversity Gain
- Diversity is used on the uplink to overcome deep fades due to multipath by combining multiple uncorrelated signals.
- Diversity antenna systems are used mostly at the BTS on the uplink.
- Diversity antenna system can be realised by physically separating two receive antenna in space or by using polarization diversity.
- Diversity gain should be considered in Link Budget Analysis whenever it is used.
- Typically a gain of 3dB is considered whenever diversity is used in the Uplink calculation.