Basically several type of antenna used in WiFi based Metropolitan Area Network, some of them are:
- Omnidirectional Antenna usually used at the Access Point (AP). It has 360-degree radiation pattern.
- Sectoral Antenna usually used at the Access Point (AP). It has higher gain than omnidirectional antenna, but normally only cover much reduced area 90 to 180-degree coverage.
- Directional Antenna usually used at the client side. It has high gain, it is normally aimed to the Access Point (AP).
Some countries mandate that the entire radio system be certified together. It means that only antennas tested with the radios can be used. This is for sure an FCC regulation, and many countries follow those regulations. That being said, enforcement of that regulation is almost impossible.
Shown in the figure is my antenna at home. It is a directional antenna, a 19 dBi parabolic antenna. It is used for 24 hour Internet connection link to the Access Point located about one (1) km away.
As it is placed about 1.5 meter on top of my two story house roof, the antenna is actually located about 9-10 meters above the ground. The antenna is screwed into a three (3) meter long 1.5-inch tubing plows half its length into the wall. The height of the antenna is enough to reduce any mutipath, or signal reflection problems at we need only about 3.5 meter clearance for the signal.
Shown in the figure is my antenna at home. It is a directional antenna, a 19 dBi parabolic antenna. It is used for 24 hour Internet connection link to the Access Point located about one (1) km away.
As it is placed about 1.5 meter on top of my two story house roof, the antenna is actually located about 9-10 meters above the ground. The antenna is screwed into a three (3) meter long 1.5-inch tubing plows half its length into the wall. The height of the antenna is enough to reduce any mutipath, or signal reflection problems at we need only about 3.5 meter clearance for the signal.
In a proper lightning protection installation is needed to protect the equipments. Protecting against lightning is a matter of reducing electrical potential, not being shorter then the guy next door. A well grounded cell tower, with proper lightning rods will be of no help to a nearby antenna. I have to admit, I am fortunate enough to have a cellular tower not too far away from my house and no lighting problem in the last two (2) years. Please install your lightning protection to protect your equipments.
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