When we introduce products to our customers, we will refer to the word antenna. Friends who have come into contact with wireless bridges will know that wireless bridges have antennas, but they are divided into built-in antennas and external antennas. Because the built-in can't see it, it is often mistakenly thought that there is no antenna. Many customers will ask whether it is good to have an antenna or not to use an antenna. Today, Xiao Bian has formally responded here. No matter what kind of wireless bridge, there are antennas, but the difference is built-in and external.
Principle of wireless bridge signal transmission: RF signal power output from the transmitter bridge is transmitted to the antenna through the feeder (cable), and then radiated by the antenna in the form of electromagnetic waves. After the electromagnetic wave reaches the receiving location, it is received by the antenna and sent through the feeder. To the receiving bridge. It can be seen that the antenna is a transmitting device of a wireless bridge signal. Without an antenna, the signal of the wireless bridge cannot be transmitted, and there is no radio communication. In other words, we often say that the wireless bridge transmission is actually transmitted through the antenna.
Moreover, there are many types of antennas, and different antennas are used according to different frequency bridges, different distances, different environments, and different occasions. According to different installation methods, there are built-in antennas and external antennas; according to the direction of the direction, there are directional antennas and omni-directional antennas; according to the frequency of differentiation there are 2.4G antennas and 5.8G antennas; according to the shape of the distinction is Yagi antenna, flat antenna, pot-shaped Antennas... With so many antennas, will it be difficult to choose?
One, built-in antenna and external antenna
1, built-in antenna
The built-in antenna refers to the antenna integrated wireless bridge, which is small in size and easy to install. It is generally used in a near-distance wireless transmission system. Generally, the built-in antenna can be used within 10 km.
2, external antenna
The external antenna is generally large. If the transmission distance is relatively long, for example, more than 10 kilometers, it is recommended to use a high-gain external antenna. The long-distance transmission of an external antenna is generally point-to-point transmission. Because of the long transmission distance, the angle will be relatively small. Except for omnidirectional antennas.
Second, directional antenna and omnidirectional antenna
1, directional antenna
In the horizontal direction, it shows radiation in a certain range of angles, and the main radiation range is like an inverted, less complete cone. It is generally used in environments where the transmission distance is long, the coverage is small, the target density is large, and the frequency utilization is high. Directional antenna signals can only be transmitted to the front. The purpose of using a directional transmitting antenna is to increase the effective utilization of radiation power, increase confidentiality, and increase anti-jamming capability.
2, Omnidirectional antenna
That is, in the horizontal direction, it shows that the radiation is uniformly 360°. The radiation range is like an apple. It has non-directionality and is generally used in environments where the transmission distance is near and the coverage is large. Omnidirectional antenna signals are transmitted in all directions. The price is low and the gain is relatively small, generally less than 12dBi.
Third, 2.4G antenna and 5.8G antenna
The choice of frequency is very simple, that is, how much the frequency of the wireless bridge is to select the corresponding antenna. If the wireless bridge is 2.4G, select 2.4G antenna; wireless bridge is 5.8G, select 5.8G antenna. Never use a 2.4G antenna for a 5.8G bridge or a 5.8G antenna for a 2.4G bridge, which can cause no signal transmission.
Look at the text and feel that the antenna is a bit complicated. Actually, it's really simple. As long as you clarify the specific situation with the staff of Lehman, we will help you configure it. You don't have to think about choices yourself.
