Cisco 7925G Deployment Guide

Cisco Unified Wireless IP Phone 7925G, 7925G-EX, and 7926G Deployment Guide
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Multipath
Multipath occurs when RF signals take multiple paths from a source to a destination.
A part of the signal goes to the destination while another part bounces off an obstruction, then goes on to the destination. As a
result, part of the signal encounters delay and travels a longer path to the destination, which creates signal energy loss.
When the different waveforms combine, they cause distortion and affect the decoding capability of the receiver, as the signal
quality is poor.
Multipath can exist in environments where there are reflective surfaces (e.g. metal, glass, etc.). Avoid mounting access points
on these surfaces.
Below is a list of multipath effects:
Data Corruption
Occurs when multipath is so severe that the receiver is unable to detect the transmitted information.
Signal Nulling
Occurs when the reflected waves arrive exactly out of phase with the main signal and cancel the main signal completely.
Increased Signal Amplitude
Occurs when the reflected waves arrive in phase with the main signal and add on to the main signal thereby increasing the
signal strength.
Decreased Signal Amplitude
Occurs when the reflected waves arrive out of phase to some extent with the main signal thereby reducing the signal
amplitude.
Use of Orthogonal Frequency Division Multiplexing (OFDM), which is used by 802.11a and 802.11g, can help to reduce issues
seen in high multipath environments.
If using 802.11b in a high multipath environment, lower data rates should be used in those areas (e.g. 1 and 2 Mbps).
Use of antenna diversity can also help in such environments.

Cisco 7925G Specifications

General

Keypad number of keys	12
Display diagonal	2 \
Display resolution	176 x 220 pixels
Call waiting	Yes
Lines quantity	6 lines
Voice codecs	G.711a, G.722, G.729a, iLBC
Security algorithms	128-bit WEP, SSL/TLS, WPA
Supported network protocols	DHCP, TFTP, DNS, SCCP, SRST
Input voltage	100 - 240 V
Dimensions (WxDxH)	52 x 20 x 127 mm
Minimum system requirements	Cisco Unified Communications Manager 4.1, 4.2, 4.3, 5.1, 6.0, 6.1, 7.0 + Cisco Unified Communications Manager Express 4.3 +
Input frequency	50/60 Hz
Storage temperature (T-T)	-30 - 60 °C
Operating temperature (T-T)	0 - 40 °C
Operating relative humidity (H-H)	10 - 95 %
Product type	IP Phone
Product color	Gray
Safety	UL 60950, CSA 22.2 No.60950, EN 60950, IEC 60950, AS/NZS 60950, IEC 60529 (IP 54)
Certification	47 CFR 15 B ICES-003 B EN 55022 B AS/NZS CISPR 22 B CISPR 22 B VCCI B EN 61000-3-2 EN 61000-3-3 KN 22 EN 55024 EN 50082-1 EN 61000-6-1 EN 300386 EN 60601-1-2 KN
Compliance industry standards	IEEE 802.11a, IEEE 802.11b, IEEE 802.11g, IEEE 802.1X, IEEE 802.11e

Weight and Dimensions

Weight	138 g