There are two standards currently available in the wireless frequency band, namely IEEE802.11G and IEEE802.11b.

The 802.11b wireless network specification is a variant of the IEEE 802.11 network specification with a maximum bandwidth of 11 Mbps.

Details:

1. IEEE ([American] Institute of Electronics and Electrical Engineers) 802.11b wireless network specification is a variant of the IEEE 802.11 network specification, with a maximum bandwidth of 11 Mbps. When the signal is weak or there is interference, the bandwidth can be adjusted to 5.5Mbps, 2Mbps and 1Mbps. The automatic adjustment of the bandwidth effectively ensures the stability and reliability of the network. Its main features are: fast speed and high reliability. In open areas, the communication distance can reach 305 meters. In closed areas, the communication distance is 76 meters to 122 meters. It is convenient for integration and networking with existing wired Ethernet networks. Lower cost 802.11a 802.11a uses the 5.8GHz operating frequency band, uses OFDM modulation technology, and the transmission rate reaches 54Mbps. 802.11g

2. 802.11g uses the 2.4GHz operating spectrum. When the transmission rate is below 20Mbps, The physical layer uses the same DSSS technology and CCK technology as 802.11b. When the transmission rate exceeds 20Mbps, the same OFDM technology as 802.11a is used at the physical layer.

802.11n

802.11n combines MIMO (Multiple Input Multiple Output) and OFDM (Orthogonal Frequency Division Multiplexing) technology and applies MIMO OFDM technology to improve wireless transmission. The quality has also greatly improved the transmission rate, from the 54Mbps currently provided by 802.11a and 802.11g to 300Mbps or even as high as 600Mbps. In terms of coverage, 802.11n uses smart antenna technology. Through an antenna array composed of multiple independent antennas, the beam can be dynamically adjusted to achieve a larger coverage area. In terms of compatibility, 802.11n uses a software radio technology, which is a fully programmable hardware platform that enables base stations and terminals of different systems to achieve interoperability and compatibility through different software on this platform. Therefore, 802.11n It can be forward and backward compatible, and can realize the combination of WLAN and wireless wide area network, such as 3G.