Range is Not an Issue

Range is Not an Issue
Range Is a Matter of Engineering
One of the major misperceptions regarding 802.11b and other wireless protocols is that the range is
limited to 100 meters and thus proves impractical as a last-mile solution. The truth is that with proper
engineering, 802.11b can reach beyond 20 miles point to point. In the quest for Public Switched
Telephone Network (PSTN) bypass, this is one of the most exciting revelations. By steering an antenna
in the direction of the subscriber's home, the service provider can bring broadband wireless to masses of
homes without stringing a single strand of copper wire, digging up a single street, or engaging in a single
legal battle for right-of-way.
Furthermore, new wireless protocols for metro area networks (MANs) provide for the construction of
wireless networks that can cover entire cities. Ad hoc peer-to-peer networks stretch the range of a
wireless network with a minimum of investment.
This chapter covers the science of antennas and how proper engineering can stretch the most modest
resources to deliver essential services to the home. Secondly, this chapter explains how 802.11b
antenna systems can be used to stretch the range of delivery out to a number of miles to blanket large
metropolitan areas and even reach out to rural subscribers. The most important part in designing a
broadband wireless network is the inclusion of the new protocol 802.16 in the deployment of wireless
metro area networks (WMANs) to feed suburban 802.11b networks. Other technologies such as mesh
networks also extend the range of broadband wireless networks.
In data networking, the success of 802.11 has inexorably linked it with radio frequency (RF) engineering.
Whereas a wired network requires little or no knowledge on the part of the installer of how data travels via
an Ethernet cable, a wireless network requires a strong knowledge of radios and antennas. The following
paragraphs provide a basic overview of wireless transmission systems.