1. The Introduction of Antennas
The Classification of Antennas
There are many kinds of antennas, according to the usage of these which can be divided into
communication antenna, navigation antenna, radio and television antenna, radar antenna
and satellite antenna. According to the antenna's radiation direction which can be divided into
Omni-directional antennas and directional antennas; According to the work wavelength which
can be divided into myriametric wave antennas, long wave antennas, medium wave
antennas, shortwave antennas, ultra-short wave antennas and microwave antennas;
According to the feeding way, which have symmetrical antennas and asymmetric antennas.
However, no matter what kind of antennas which has its frequency scope of work, and in its
frequency range, its work efficiency is relatively high.
The Difference between WIFI Antenna and WLAN Antenna
What is the difference between WIFI Antenna and WLAN AntennaI would like to introduce
you the difference between WIFI Antenna and WLAN Antenna. The first difference is that
they have different definition; the full name of WLAN antenna is Wireless Local Area
Networks, which is a data transmission system in use of radio frequency (Radio Frequency
RF) technology. The appearance the technology is not used to replace the WLAN Networks,
but used to make up for the shortage of cable local area network, so as to achieve the
purpose of network extension, that is, which makes the wireless local area network can use
simple access structure that let users get through it. It can help to realize the cable free and
no distance limit and communication. WLAN uses the ISM(Industrial, Scientific, Medical)
radio frequency for communications. mobile WIFI antenna
is a wireless networking technology which connected to the computer through the network
before and now via radio waves.
The second difference between WIFI and WLAN
The second difference between WIFI and WLAN is that WiFi is included in WLAN, and both
two have the different power of the transmitted signal, and the coverage is different. The
coverage of WiFi is up to about 300 feet (about 90 meters), but the maximum coverage of
WLAN (plus antenna) to 5KM.
The third difference between WIFI and WLAN
The third difference between WIFI and WLAN is that they have different wireless signal
coverage. The biggest advantage of WIFI is the high transmission speed which can achieve
11 MBPS, in addition, its effective distance is also very long. At the same time, it is also
compatible with the existing various 802.11 DSSS equipment.

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