3G Antenna Antenna Selection:
Antenna selection principle:
According to the design of the distributed system, the installability of the antenna is considered to decide which type of antenna to use. The leaky cable does not need an antenna. Antenna units commonly used in indoor distributed systems are:
(1) Indoor ceiling antenna unit
(2) Indoor Wall Mount Antenna Unit
(3) Cup-shaped ceiling unit: ultra-small size, suitable for various installation-restricted applications such as the interior of small elevators and the interior of small ceiling bulbs embedded in small private rooms.
(4) Plate antenna unit: It has different sizes and can be used in elevator walkways, tunnels, subways, corridors and other applications in different occasions.
The above antenna introduction mainly focuses on transmission. I personally think that the principle of reception is similar to that of transmission. There is a power issue to consider when transmitting, because if the antenna is not done well, if the power is too large, the transmitted power will easily be reversed if it is not transmitted (simply put, the standing wave is large, causing power backlash) to damage the machine. . A friendly reminder: For friends who use high-power routers and network cards, if you are not sure about the technical indicators of the homemade antenna, try to lower the power as much as possible, just enough.
Regarding the choice of the antenna, the key is to look at the usage environment. If it is a residential environment below the 6th floor, the field of vision is not too wide, and there are obstacles between 20-50 meters. It is recommended to use an omnidirectional or flat-panel antenna. Personal recommendation: 9db, 8db, 7db. If it is a small high-rise, or the edge of the cell environment (open field of view, the signal is far away). It is recommended to use Yagi, a tablet above 14db. This type of antenna is recommended for use within a range of 100-800 meters.
Friends who are more than 1,000 meters away, have a flamboyant personality, and like to chat with urban management can choose Grid, Wei-Xingguo.
Antenna material selection: For drawings with dimensions: for example, the increase of the reflector can increase a little effect, and the others do not need to be changed according to the drawings.
