For antenna placement, there are mainly two types:
1) indoor Antenna
2) outdoor Antenna
Indoor antennas are generally small antennas, generally used as WiFi router antennas, Phones, Laptops, and USB WiFi Adapters.
Outdoor antennas are specially designed for long-range They are usually mounted on the rooftop and can transmit or receive radio waves to very long distances.
Most of the Home routers antennas have omnidirectional antennas that emit radiations equally in a single plane.
The direction of radiation emitted will be perpendicular to the direction you point the antenna. That means, If your WiFi router antenna position is vertical, it will emit radiation in a horizontal plane. If you are pointing WiFi antenna horizontally, waves will be emitted vertically.
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