Aastra NeXspan C, Руководство по установке

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Page 16 01/2007 AMT/PTD/PBX/0020/2/4/EN
• Roaming:
mechanism for changing the channel for a cordless handset during communication or when no
call is set up (roaming).
• Handover:
mechanism for changing the base station during communication.
Figure1: Example deployment
1.5.2 Overlapping radio areas
The radio coverage of a site is established by positioning basic radio areas next to each other.
However, to guarantee quality of service for the entire site, the radio areas must overlap on the
horizontal and vertical axes. This overlap is required so the roaming and handover phases take
place in good radio conditions.
During deployment you must measure the significant values (CRC/RSSI) of the radio area
studied and note them on the site plan. These measurements must be taken on the horizontal
and vertical axes. The six measurements must indicate the following three values: the CRC, the
RSSI, and the distance between the point where the measurement was taken and the base
station concerned.
Figure2: Overlapping radio areas
++
+
++
+++
+
: DECT base station
8-base station cell
radio area
centre of radio area
(3 overlapping base stations maximum)
bottom
RSSI < 3DH
CRC <
BS
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