Last time we talked about what matters to pay attention to outdoor AP deployment, some friends asked, how should we choose the antenna that matches the outdoor AP? Let's talk about the outdoor AP and its antenna today!
For wireless coverage in some communities, scenic spots, parks and other places, outdoor APs are often used for building. Generally, in order to achieve good results, they often choose matching antennas. Now, let's briefly talk about some small knowledge of selecting antennas.
There are many types of antennas used outdoors, and antennas used by different needs or different equipment may be different.
Wireless WiFi network signal coverage projects generally use four methods: wireless AP + omnidirectional antenna, wireless AP + flat antenna (a type of directional antenna), wireless AP + sector antenna, wireless AP + ceiling antenna.
Scenario analysis
① If the floor is not high, it is a bungalow, and the field of vision is wide. It can be covered with an omnidirectional antenna, which can achieve 360 ° WiFi omnidirectional coverage, and the coverage can reach 100-300 square meters, which is relatively large.
② If the floor is too high and it is a high-rise building, you can use a directional antenna to cover it from the next building. Long distance, strong penetration, but narrow range, suitable for small area coverage.
③ If there are many buildings and the area is large, such as schools, communities, etc., you need to use fan antennas to cover them. The sector antenna is a professional-grade signal coverage antenna with a horizontal angle of 120 degrees, a wide range, and a strong signal. Operators such as telecommunications / mobile / Unicom also often use this type of antenna.
④ If the floors are relatively tight and there are many rooms, it is not convenient to install antennas outdoors, you can use indoor ceiling antennas to cover them. This coverage method requires a cable, and the signal from the wireless AP antenna is connected to a power divider and connected to multiple indoor antennas to each floor. The effect is ideal. If two locations need to share the network, a local area network needs to be set up. Generally, two wireless APs are used to bridge.
You can choose the appropriate antenna based on the coverage and distance:
Three types of antennas are generally used: directional 65 ° / 90 ° antennas, flat directional antennas, and parabolic antennas (also called grid antennas).
If the distance between the two locations is 100-300 meters, wireless AP + directional 65 ° / 90 ° antenna is generally used.
If the distance between the two locations is 300-1 kilometers, a wireless AP + flat directional antenna (small flat) is generally used.
If the distance between the two locations is 2-5 kilometers, a wireless AP + flat directional antenna (large flat) is generally used.
If the distance between the two locations is 5-10 kilometers, wireless AP + parabolic antenna is generally used. The angle of the flat antenna is about 30 degrees and the angle of the parabolic antenna is 15 degrees. Therefore, the transmission distance of the parabolic antenna is longer.
In addition, the construction personnel also need to pay attention to these when installing: the directional antenna should be about 3 meters higher than the top of the building, and it should be about 30 meters away from the nearest obstacle. In this way, obstacles can be bypassed to the maximum extent to ensure high-speed and stable transmission of the signal; and the distance between the wireless AP and the high-gain antenna should generally not exceed 3 meters.
