Wireless Standards and Regulatory Committees

Many people benefit from the availability of wireless Internet access as they travel to various parts of the world. Without regulatory committees and organizations to ensure the proper use and interoperability of equipment, it's likely that people could not connect from place to place. To ensure that certain rules governing the use of wireless RF are adhered to, numerous country-specific organizations and global committees monitor standards and usage. This chapter discusses some of them.

The Federal Communications Commission (FCC) is an independent agency in the United States that regulates communication methods. It is held directly responsible by Congress. It is the FCC in the United States that governs the frequency ranges that can be used without a license, the transmit power of devices, the types of devices that can be used indoors as well as outdoors, and how the various types of hardware can be used. The FCC exists because of the Communications Act of 1934.

Note: The FCC website is http://www.fcc.gov.

When it comes to the FCC and Cisco wireless, it's important to know the requirements defined in FCC - Part 15 - Antenna Requirements. This federal requirement states that antennas must use a unique nonstandard connector that cannot be acquired easily. The reason for not being acquired easily is to ensure that home users and noncertified installers cannot easily deploy an antenna that goes beyond the regulated values. For this reason, Cisco uses a connector known as the Reverse-Polarity-Threaded Neil-Concelman (RP-TNC) connector, as shown in Figure 2-1.

Figure 2-1 RP-TNC Connector

What makes this connector unique is that the center contacts are reversed so that you can't use a store-bought antenna with a Cisco wireless device. If you did so, you might violate the FCC regulatory requirements.

In addition to the antenna rules, the FCC defines power output rules that must be followed. There are rules for everyday people to follow, and rules for people who are considered professionals in the field. A professional has a little more leeway than someone who buys a wireless device at the local electronics store. To get an idea of these rules, you can look at the 2.4-GHz EIRP Output Rules. Effective Isotropic Radiated Power (EIRP) is a way to measure the amount of energy radiated from an antenna. EIRP is an important concept to understand, especially when you're dealing with regulatory bodies. It's important that the EIRP not exceed that mandated by the governing bodies. These rules are designed for point-to-point scenarios as well as point-to-multipoint. The point-to-point rules are as follows:

■ You can have a maximum of 30-dBm transmitter power with 6-dBi gain of antenna and cable combined.

For point-to-multipoint scenarios, you are allowed the same maximum EIRP and the same maximum transmitter power and antenna gain; however, you can exceed the 36-dBm EIRP rule using a 3:1 ratio of power to gain.

Table 2-2 compares the FCC maximum requirements for point-to-point to the Cisco maximum.

Table 2-2 FCC Antenna Requirements Versus Cisco Standards for Point-to-Point Environments ; Key.

Transmitter Power

Maximum Gain

EIRP

FCC Maximum

30-dBm

6-dBm

36-dBm

Cisco Maximum 20-dBm 36-dBm 56-dBm

Cisco Maximum 20-dBm 36-dBm 56-dBm

Table 2-3 compares the FCC maximum requirements for point-to-multipoint to the Cisco maximum.

Table 2-3 FCC Antenna Requirements Versus Cisco Standards for Point-to-Multipoint Environments

Transmitter Power

Maximum Gain

EIRP

FCC Maximum

30-dBm

6-dBm

36-dBm

Cisco Maximum 20-dBm 36-dBm 36-dBm

Cisco Maximum 20-dBm 36-dBm 36-dBm

ETSI

The European Telecommunication Standards Institute (ETSI) is the not-for-profit organization that standardizes the frequencies and power levels used in Europe as well as many other countries. The European Commission (EC) recognizes ETSI as an official European Standards Organization. Many of the mandates for wireless usage come from the EC. Then, ETSI defines various standards based on these mandates. According to the ETSI website, the ETSI has almost 700 members in 60 countries.

Similar to the FCC, the ETSI has 2.4-GHz EIRP output rate standards that you should be familiar with. The ETSI's rules, however, are different from the FCC's rules. ETSI defines 20-dBm EIRP on point-to-multipoint and on point-to-point with 17-dBm maximum transmit power with 3-dBi gain. In a way, this is easier to remember, because these numbers are the same value for both point-to-point and point-to-multipoint connections. Of course, a professional installer can increase the gain as long as he or she lowers the transmit power below 17 dBm at a ratio of 1:1. Therefore, a professional installer could drop the transmit power by 1 dBm and increase the gain by 1 dBm and still stay within the guidelines.

Table 2-4 compares the Cisco standards to the ETSI standards for EIRP. The table shows the governing body maximum transmitted power, maximum gain, and EIRP compared to that of the Cisco integated antennas. You can see that the Cisco antenna has a transmit power of 17 dBm and a maximum gain of 2.2 dBi and ends up with an EIRP of 19.2 dBm, which is lower than the 20 dBm allowed by the governing bodies. If you reduced the transmit power to 15 dBm and increased the maximum gain to 5 dBi, the resulting EIRP would be 20 dBm, which is still within the guidelines of the governing body. Likewise, reducing the transmit power to 13 dBm and increasing the gain to 7 dBi keeps the EIRP at 20 dBm—within the guidelines.

Table 2-4 Cisco Versus ETSI EIRP Standards for Point-to-Point and Point-to-Multipoint T-fy_ Environments

Transmitter Power (dBm)

Maximum Gain (dBi)

EIRP (dBm)

Governing Body Maximum

17

3

20

Cisco Integrated Antennas

17

2.2

19.2

Reduced Tx Power

15

5

20

Reduced Tx Power

13

7

20

Reduced Tx Power

7

13

20

Reduced Tx Power

0

20

20

The Institute of Electrical and Electronics Engineers (IEEE) is a not-for-profit organization that has more than 370,000 members globally. It has 319 sections in ten geographic areas. It has defined more than 900 standards and has another 400 in development.

Note: For a history of the IEEE, see http://ieee.org/web/aboutus/history/index.html.

The IEEE's "Wireless Standards Zone" is dedicated to standards that are related to wireless technology. Here you can find information about the 802 protocols, such as the following:

■ 802.11: The Working Group for Wireless LAN

■ 802.15: The Working Group for Wireless PAN

■ 802.16: The Working Group for Broadband Wireless Access Standards

Note: You can find the Wireless Standards Zone at http://standards.ieee.org/wireless/ and an overview of the aforementioned working groups at http://standards.ieee.org/wireless/ overview.html.

This book focuses mainly on the 802.11a, 802.11b, 802.11g, and 802.11n protocols. These protocols are for wireless LANs.

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  • afwerki
    What are wireless regulatory committes?
    9 months ago

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