unity-gain frequency
A: As frequency increases the performance of the amplifier decreases to point where because of its internal make it reaches no gain or unity gain. Or it can be unity gain as designed like for a signal buffer
Antenna gain is determined by factors such as antenna size, shape, design, and directivity. The physical properties of the antenna, its operating frequency, and the surrounding environment also play a role in determining its gain. Additionally, the efficiency of the antenna and any losses incurred during transmission or reception impact the overall gain.
increases by 6 dB
The size of an antenna depends upon the frequecny of the RF signal and the gain.
EIRP (Dbm)= Output Power(Dbm)-Losses(from cables & adapters)+Antenna Gain(Db)
microstip patch array antenna is basically ,thecollection of antenna that give the double directive gain
Antennas provide so called passive gain, which means it comes from particular shape of the antennaThe gain of an antenna is a passive phenomenon - power is not added by the antenna, but simply redistributed to provide more radiated power in a certain direction than would be transmitted by an isotropic antenna. If an antenna has a gain greater than one in some directions, it must have a gain less than one in other directions, since energy is conserved by the antenna.SOURCE: wikipedia.com
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Gain in antenna propagation refers to the measure of the directionality and efficiency of an antenna in transmitting or receiving electromagnetic waves. It represents the ability of the antenna to focus its radiated power in a specific direction, usually compared to an isotropic radiator. A higher gain indicates a more focused radiation pattern and improved performance in that direction.
Antenna gain of base station for a specific user depends on antenna pattern, antenna orientation (azimuth and tilt) and user's coordinates with respect to base station.
A simplified explanation is that the antenna does for radio waves what a lens does for light because of physics.