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Chapter 3. Regulating the Use of 802.11 WLANs

This chapter covers the following topics:

Early Spread-Spectrum Regulations

RF Regulatory Domains

WLAN Frequencies of Operation

Dynamic Frequency Selection and Transmitter Power Control with 801.11h

Regulatory Channel Selections

Maximum Transmitter Power Levels

Amplifiers

Antenna Connectors and Remote Antennas

Health and Safety

Plenum Locations

scalability, portability, and a host of other factors that affect the overall usability of WLANs.

In 1985, the United States Federal Communications Commission (FCC) enacted standards for the commercial use of spread-spectrum technology in the Industrial, Scientific and Medical (ISM) frequency bands. These bands included 900-MHz, 2.4-GHz, and 5-GHz areas. Shortly thereafter, the Canadian regulatory body, Industry Canada (IC; once called the Department of Communication, or DoC) followed suit, and many other countries started to enact regulations surrounding spread spectrum and the use of these frequency bands for commercial applications. Today many countries permit the use of WLANs in at least some of these bands; however, regulations vary from country to country; therefore, is important to review, understand, and abide by the regulations covering the country of installation.

Most countries set limitations covering areas of frequency use, transmitter power, antenna gain, Effective Isotropic Radiated Power (EIRP) limits, modulation techniques, and other criteria related to radio transmissions.

Other regulations also affect WLAN usage, besides those set forth by the authorities governing the RF frequencies and transmitters. Some regulations relate to the absorption of RF by the human body, other regulations relate to usage in health-care and hospital facilities, and still others relate to installation locations. This chapter covers many of these regulations that can impact your WLAN project.