LG PX8700, Service Manual

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PX8700
LG Electronics Inc.
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generates interference in relation to the signals of all the other mobile stations.
Total interference from all the adjacent cell sites is the ratio of interference from all the cell sites versus total
interference from other mobile stations in the same cell site (about 65%). In the case of directional cell site, one
cell normally uses a 120
°
sector antenna in order to divide the sector into three. In this case, each antenna is
used only for 1/3 of mobile stations in the cell site and accordingly, interference is reduced by 1/3 on the average
and the capacity that can be supported by the entire system is increased by three times.
2.7 Soft Capacity
The subscriber capacity of the CDMA system is flexible depending on the relation between the number of
users and service classes. For example, the system operator can increase the number of channels available for
use during the busy hour despite the drop in call quality. This type of function requires 40% of normal call
channels in the standby mode during the handoff, in an effort to avoid call disconnection resulting from the lack
of channels.
In addition, in the CDMA system, services and service charges are classified further into different classes so that
more transmit power can be allocated to high class service users for easier call set-up; they can also be given
higher priority of using hand-off function than the general users.