Cisco 7925G - Unified Wireless IP Phone VoIP User Manual

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Cisco Unified Wireless IP Phone 7925G Administration Guide for Cisco Unified Communications Manager 7.0(1)
OL-15984-01
Chapter 2 Overview of the VoIP Wireless Network
Understanding WLAN Standards and Technologies
Radio Frequency Ranges
WLAN communications use the following RF ranges:
• 2.4 GHz—Does not require licensing. To reduce interference within this bandwidth, WLANs
transmit on non-overlapping channels, which are typically limited to three channels, although Japan
uses four channels.
Many devices operate in the 2.4 GHz bandwidth including cordless phones and microwave ovens
and can interfere with wireless communications. Interference does not destroy the signal, but can
reduce the transmission speed from 11 Mbps to 1 Mbps. RF interference can affect voice quality
over the wireless network.
• 5 GHz—Divided into several sections called Unlicensed National Information Infrastructure (UNII)
bands and has four channels each. The channels are spaced at 20 MHz to provide non-overlapping
channels and more channels than 802.11b or 802.11g.
Table 2-1 lists frequency band ranges and operating channels by regulatory domain.
802.11 Data Rates, Tx Power, Ranges, and Decibel Tolerances
Table 2-2 lists the Tx power capacities, data rates, ranges in feet and meters, and decibels tolerated by
the receiver by 801.11 standard.
Ta b l e 2-1 Frequency Bands and Operating Channels by Regulatory Domain
Regulatory Domain Frequency Band Range Operating Channels
Federal Communications
Commission (FCC)
2.412-2.462 GHz 11 channels
Product number is
CP-7925GA-K9
5.15-5.25 GHz (UNII-1)
5.25-5.35 GHz (UNII-2)
5.725-5.825 (UNII-3)
5.470 - 5.725 (DFS)
8 of 11 channels
5.47-5.725 GHz
(pending approval
11 channels
ETSI (Europe) 2.412-2.472 GHz 13 channels
Product number is
CP-7925GE-K9
5.15-5.725 GHz 19 channels
Japan 2.412-2.472 GHz 13 channels (ODFM)
Product number is
CP-7925GPC-CH1-K9
2.412-2.484 GHz 14 channels (CCK)
5.15-5.35 GHz 8 channels
World
Product number is
CP-7925GW-K9
— Uses 802.11d to identify band
ranges and channels

Cisco 7925G - Unified Wireless IP Phone VoIP Specifications

General

Brand	Cisco
Model	7925G - Unified Wireless IP Phone VoIP
Category	IP Phone
Language	English