One of the main technical parameters of antennas is the angle of radiation, often mistakenly interpreted as critical angle operation of the antenna. Nothing less vicious. The antenna radiates and works much more than just the technical data given in the angle of radiation. Example The antenna has the following specifications: - Gain: 14dBi - Horizontal beamwidth: 60 ° - Vertical beamwidth: 25 °
For the horizontal angle
These data indicate that the antenna at 30 degrees to the right and left of the direction in which it is set, working at a gain by 3 dB less than that specified in the technical data, in this case the 11dBi. Following this line of thinking, going beyond the main beam of the antenna, for example to 45 ° right and left of the center of the main beam, we can expect a gain 6 .. 8 dBi (depending on the characteristics of the antenna). Conclusion: The antenna working outside the declared angle, but with less gain.
For the vertical angle
As for the horizontal angle, remember that the antenna working well beyond the declared angle, but with less gain. This is especially important if you are installing a base station equipped with an omnidirectional antenna. Near the antenna, even without being in the main beam, we will take back a good signal, because we are very close to the transmitter. Of course, an important factor is the optical visibility of the receiver and transmitter (clear line of sight), but there are no rules, and often "under the building", even though you do not see the antenna, the signal is of good quality. calculate the radius of coverage