How to orient the position of directional Wi-Fi antennas to get long-distance links
In this article we will describe simple methods to apply to improve WiFi coverage of an Access Point (AP) or a WiFi receiver. To avoid the loss of signal or even the connection cut, it is essential to align the directional antennas.
Currently, most powerful outdoor USB WIFI adapters are equipped with directional antennas. A directional antenna focuses all its gains in specific directions for greater performance.
In all WiFi connection two actors are involved. On the one hand there is the Wi-Fi transmitter, or access point, conicido by the abbreviations AP (access point). On the other side is the Wi-Fi receiver or Wi-Fi client. To achieve a long-distance link it is essential that the two points are covered by panel or directional antennas, and that they are also at the same height or within the coverage angle and also well aligned.
As an example we can take the CPE Melon N828 with directional antenna. This CPE can be configured as both AP and Client and its directional panel antenna concentrates the emission energy on the front panel with 65 ° horizontal and 35 ° vertical on a graph like this.
All WiFI receivers that are placed within that coverage will be able to get a good signal. This phenomenon can also be explained as the light source of a flashlight, the width of the light beam will be the coverage area.
We must remember that directional antennas work horizontally, for this reason some users when they start using them say they see fewer WiFi networks than before. This phenomenon is logical, because since the energy is finite, a wider angle in the horizontal leads to a narrower vertical beam width at a shorter distance. The improvement of the directional antennas eliminates the interference of networks in the near environment and also consists of extending the coverage to the front eliminating it, backwards and decreasing it much in the vertical.
1-Process of alignment of directional WiFi antennas.
As we have explained, the adjustment of the position and the orientation on the outside of the antennas are the key to achieving a long distance connection. Now let’s explain how to perform the alignment process of the antenna in a city or in the open field.
1.1 – On the side of the transmitter or access point AP.
* Configure the CPE router or antenna in AP sender mode. After configuring the software, locate the antenna at a point high enough to avoid interference.
* Adjust the position of the front panel towards the front and direct it in the direction of the client with the help of tools such as map, GPS, compass or telescope.
* Put the antenna panel in a position as vertical as possible. A plumb or level, can help in this work.
Tip: Agood AP access point can be the Melon CPE or a Ubiquiti Nanostation. Also an AGA-2424T parabolic antenna connected to a coaxial antenna cable router.
1.2- Remote client. WiFi receiver
* Direct the antenna towards the AP transmitter, locate the remote AP and then turn the client device in that direction.
* Locate the client antenna at the same height to find the signal and connect to the root of the AP antenna. In this work it is very useful to use a telescope and a laser pointer.
If we align the laser pointer with the antenna and rotate it when the laser point all the AP transmitter, we will have the two antennas aligned. This alignment can be done with the help of another person to tell us when the pointer is touching the antenna or with a telescope.
After connecting you can adjust the search for the best signal quality using a WiFi scanner application such as Alfa WiFI scanner. This application is distributed in the packages of all the powerful WIFI adapters of Alfa Network.
Tip: A good receiver or WiFi client can be a Melon N4000 36dbi Panel antenna. Also the Alfa UBDO USB RT3070, or a satellite dish connected to any USB adapter with RT3070 chip. At the end of this article we explain how to add a special OpenWrt router with USB to our new USB WIFI client so that it repeats the internet once captured by the long-range antenna.
2-Use of the Alfa WiFi Scanner application to align and improve the quality of WiFi connections.
The ALFA WiFi Scanner software is an application included in the drivers CD for Alfa Network products. It can be used to explore the Wi-Fi networks of the environment and connect to them just as with the native Windows application, but it also has WiFi monitoring and alignment of directional antennas utilities.
The ALFA WiFi Scanner software will help you search for Wi-Fi networks and check the intensity with which you receive it. It also allows you to select your preferred network to connect to. With the utility of ALFA it is not necessary to use the Windows Wi-Fi Zero software to do the wireless configuration.
Alfa WiFi scanner is an application of universal use for all WiFi adapters that can replace the native program of Windows ZERO. It does not require installation and SE can be run from the desktop or from any Windows folder.
When you open the application it gives you graphical information of all the WIFI networks of the environment and the power of emission of all of them. The graphic shows in real time the name, power and type of encryption of each access point. By selecting one and clicking we can connect after entering the password or “password”.
The best way to align two directional antennas is with a laser pointer. But there are cases in which this possibility is not available, so it is very helpful to use the Alfa WiFi scanner software to measure the quality of the signal and reorient the antenna. It also has a localization utility of the WiFi network in Google Maps and also the option of adding an exact position with GPS coordinates.
A good way to get a stable WiFi connection even at more than 5km is to face two Alfa AGA-2424 satellite dishes. Two of these antennas are faced and configured one as AP and the other as client get the longest distances for stable WIFI connections. The ALFA AGA-2424T Satellite dish has a coaxial WiFi antenna cable connector that allows it to be installed in a router as well as an ALFA USB receiver AWUS036NEH as a client.
Once with this WIFI parabolic KIT we have achieved a stable reception by WiFI, on the client side, we can add an OpenWrt router that distributes the signal received by Alfa’s USB WiFI receiver. By adding a router to the USB card we can convert a WiFi client into a new access point, repeating for example the internet that we have taken over WiFi over a long distance.