IEEE 802.11 STANDARD
The IEEE 802.11 standard has enjoyed unprecedented success over the past decade. 802.11 chipset shipments topped 1 billion in 2011, a threefold increase compared with 2010. The recent surge in demand for 802.11 chipsets is driven by a large array of sleek personal devices that require high-speed wireless connectivity. A decade ago, laptops replaced desktop computers as the main driver for 802.11. Smartphones and tablets are now beginning to replace laptops as the key driver for 802.11. The 802.11 standard is the most popular wireless standard to date and possibly the easiest to read. It is also known by the trade name of Wireless Fidelity (or Wi-Fi). The 802.11 wireless LAN is a cost-effective alternative to a wired Ethernet LAN in connecting end-user devices. Unlike wired networks, bandwidth can be reused in 802.11 wireless networks. 802.11 has become an increasingly important extension of cellular service. Cellular providers rely on 802.11 to offload voice, data, and video traffic from their crowded and expensive licensed spectrum to a wireline broadband connection. This also benefits users, who do not have to pay more when crossing the bandwidth caps enforced by these providers. Similarly, wireline providers with no cellular service are using 802.11 to expand their broadband service offerings in homes and public areas. This chapter provides a detailed coverage of 802.11, with an in-depth review of the key PHY and MAC technologies.