- IEEE 802.11 Standard Overview
- IEEE 802.11 Physical Layers
- IEEE 802.11 Frequency Hopping Spread Spectrum (FHSS)
- IEEE 802.11 Direct Sequence Spread Spectrum (DSSS)
- IEEE 802.11b High-Rate Direct Sequence Spread Spectrum (HR-DSSS)
- IEEE 802.11a Orthogonal Frequency Division Multiplexing (OFDM)
The IEEE 802.11b version of the standard is a data rate extension of the initial 802.11 DSSS, providing operation in the 2.4GHz band with additional data rates of 5.5 and 11Mbps. All primary wireless LAN vendors offer 802.11b radio cards and access points. These products are currently the basis for nearly all wireless LANs that companies are installing today. In addition, the IEEE 802.11 working group is considering an enhancement of the standard to double this data rate to 22Mbps. Several wireless LAN vendors will be releasing the 22Mbps versions of their products in early 2001.
802.11b products exhibit similar advantages and disadvantages of 802.11 DSSS, but it is unlikely that 802.11b products will become obsolete within the next three years. In addition, the higher data rates of 802.11b lower the effective range of the radios to typically 150 feet when transmitting at 11Mbps.