It is abundantly clear that wireless networks are a very important part of our future, promising to dramatically change the way society and industry function. Wireless networks fall into the same domains as wireline networkswide area networks (WANs), metropolitan area networks (MANs), local area networks (LANs), and personal area networks (PANs)and are applied in support of a growing number of applications, including mobile (such as cellular and PCS systems), fixed (as in wireless local loop), broadcast (television), and sensor-based (such as RFID) networks.
This chapter explores wireless wide area network (WWAN) standards and systems. WANs can be global, national, or regional in scope. Traditional WWAN solutions include cellular radio and PCS networks (including analog and digital cellular) as well as early wireless data networks (i.e., Cellular Digital Packet Data [CDPD] and packet radio). Newer generations are focused on supporting high-speed data as well as video and multimedia, with increased emphasis on mobile content delivery.
Given the basic human desire and need for freedom of movement, it is little surprise that the demand for wireless network solutions is enormous. With the introduction of cellular communications, we saw an increasing demand for wireless services. The growth was so rapid that by 2002, we witnessed a major shift in network usage: For the first time in the history of telecommunications, the number of mobile subscribers exceeded the number of fixed lines. And that trend continues. According to the ITU, at year-end 2004, the total number of mobile subscribers was 1.75 billion, while the total number of fixed lines worldwide was 1.2 billion. By September 2005, the number of mobile subscriber connections exceeded 2 billion. Although the history of cellular networks has been rather brief, it has already seen three generations, the fourth is emerging, and a fifth generation is on the drawing boards:
An intermediate third generation, 3.5G, is introducing many enhancements designed for services running over an IP backbone, including high-speed data and video. Key 3.5G standards include HSDPA, HSUPA, and HSOPA.
Part I: Communications Fundamentals
Telecommunications Technology Fundamentals
Traditional Transmission Media
Establishing Communications Channels
Part II: Data Networking and the Internet
Data Communications Basics
Local Area Networking
Wide Area Networking
The Internet and IP Infrastructures
Part III: The New Generation of Networks
Broadband Access Alternatives
Part IV: Wireless Communications
Wireless Communications Basics
WMANs, WLANs, and WPANs
Emerging Wireless Applications