Views:45 Author:Fiberall Technology (Shenzhen) Co., Ltd Publish Time: 2019-01-30 Origin:www.fiber-all.com
In our ONU / OLT description , you always see 802.11 B/G/N . So what is this?
IEEE 802.11b is a standard of WLAN . The carrier frequency is 2.4GHz , its transmission speed is 11Mbit/s . IEEE 802.11b is the most famous and most popular wireless LAN standard, It is also erroneously labeled as Wi-Fi sometimes. In fact Wi-Fi is a trademark belong to the wireless local area network alliance (WLANA) but the trademark do not have relations with the IEEE 802.11b standard. There are 14 channels which bandwidth is 22MHz each can be used in the 2.4 GHz-ISM band . The subsequent standard of IEEE 802.11b is IEEE 802.11g , the transmission rate of IEEE 802.11g is 54Mbit/s.
IEEE 802.11g : Equipments based on 802.11b and 802.11g are compatible . In order to improve the transmission rate of 802.11g , it adopts 2.4GHz band , using CCK technology and 802.11b (Wi-Fi) to realize backward compatible , at the same time , in order to support data flow reach 54Mbit/s it uses OFDM technology and it provides larger bandwidth which is 1.5 times of 802.11a. There is Wi-Fi compatibility problem between 802.11g and 802.11a, so dual band technology 802.11a+g(=b) was emerged as the times required to bridge this gap, it integrated 802.11a and 802.11g very well and work on both 2.4GHz and 5GHz bands,it also obey 802.11b/g/a standards, and backward compatible with 802.11b,it makes users able to connect with the existing or future 802.11 network in a simple way.
IEEE 802.11n : In January 2004, IEEE announced a new unit to develop 802.11 new standards. The data transmission speed is estimated to reach 540Mbit/s ( speed in the physical layer rate must be higher ), the new standard should be 50 times faster than 802.11b, and about 10 times faster than 802.11g. 802.11n will support much longer distance than the current wireless network. 802.11n also added standard for MIMO (multiple-input multiple-output). MIMO use multiple transmit and receive antennas to realizes higher data transmission rate .MIMO also use Alamouti coding schemes to increase the transmission range.
Fiberall GPON EPON Optical Line Terminal (OLT) and Optical Network Unit (ONU) products adopts these WiFi standards and they are universal worldwide.