Cisco Cisco Aironet 350 Wireless Bridge 데이터 시트

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Reference Guide 
Cisco Aironet Antennas and Accessories 
Overview 
Executive Overview 
This antenna reference guide explains issues and concerns about antennas used with a Cisco
®
 Aironet
®
 wireless 
LAN system or wireless bridge system. It details deployment and design, limitations and capabilities, and basic 
theories of antennas. This document also contains information about the Cisco antennas and accessories, as well 
as installation scenarios, regulatory information, and technical specifications and diagrams of the available 
antennas. 
Overview of Antennas 
Each Cisco Aironet radio product is designed to perform in a variety of environments. Implementing the antenna 
system can greatly improve coverage and performance. 
To optimize the overall performance of a Cisco wireless LAN, it is important to understand how to maximize radio 
coverage with the appropriate antenna selection and placement. An antenna system comprises numerous 
components, including the antenna, mounting hardware, connectors, antenna cabling, and in some cases, a 
lightning arrestor. For a consultation, please contact a Cisco Aironet partner at: 
. 
Cisco partners can provide onsite engineering assistance for complex requirements. 
Radio Technologies 
In the mid-1980s, the U.S. Federal Communications Commission (FCC) modified Part 15 of the radio spectrum 
regulation, which governs unlicensed devices. The modification authorized wireless network products to operate in 
the industrial, scientific, and medical (ISM) bands using spread spectrum modulation. This type of modulation had 
formerly been classified and permitted only in military products. The ISM frequencies are in three different bands, 
located at 900 MHz, 2.4 GHz, and 5 GHz. This document covers both the 2.4- and 5-GHz bands. 
The ISM bands typically allow users to operate wireless products without requiring specific licenses, but this will 
vary in some countries. In the United States, there is no requirement for FCC licenses. The products themselves 
must meet certain requirements to be certified for sale, such as operation under 1-watt transmitter output power (in 
the United States) and maximum antenna gain or effective isotropic radiated power (EIRP) ratings. 
The Cisco Aironet product lines utilize both the 2.4- and 5-GHz bands. In the United States, three bands are 
defined as unlicensed and known as the ISM bands. The ISM bands are as follows: 
● 
900 MHz (902-928 MHz) 
● 
2.4 GHz (2.4-2.4835 GHz) - IEEE 802.11b 
● 
5 GHz (5.15-5.35 and 5.725-5.825 GHz) - IEEE 802.11a, HIPERLAN/1 and HIPERLAN/2. This band is also 
known as the UNII band, and has three subbands: UNII1 (5.150-5.250 GHz), UNII2 (5.250-5.350 GHz), and 
UNII3 (5.725-5.825 GHz)