ZXG10 BS21 (V2.2) Compact Outdoor BTS for GSM Maintenance Manual
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Confidential and Proprietary Information of ZTE CORPORATION
4.
Congestion rate of the radio system of the Unicom mobile network in
busy hour. G4 < 5 %
G4 reflects the congestion situation of the signaling channel (SDCCH)
and voice channel (TCH) of the radio system of the Unicom GSM
mobile network, with the radio subsystem of the local network as the
statistics point.
G4 = (1 - (1 – congestion rate of the signaling channel in busy hour) ×
(1 – congestion rate of the voice channel in busy hour (including
handover) ) × 100% congestion rate of the signaling channel in busy
hour = total overflow times of the signaling channel in busy hour/total
call attempt times of the signaling channel in busy hour
Congestion rate (including handover) of the voice channel in busy hour
= total overflow times (including handover) of the voice channel in
busy hour/total call attempt times of the voice channel in busy hour
5.
The worst cell ratio of the radio system of the Unicom mobile network
in busy hour. G5 < 5%
G5 reflects ratio of the cells having high call loss rate of the radio
system of the Unicom GSM mobile network, with the wireless
subsystem of the local network as the statistics point.
G5= Quantity of the worst cells/Total quantity of the cells having the
traffic per channel not less than 0.1 Erlang × 100%.
Definition of the bad cell: A bad cell is the cell having a call drop rate
(including handover) of the voice channel greater than 3% and a
average traffic per channel not less than 0.1 Erlang while less than 0.6
Erlang.
Call drop rate (including handover) of the voice channel in busy hour =
total call drop times of the voice channel in busy hour/total utilization
times (including handover) of the voice channel (TCH) in busy hour ×
100%
6.
The overflow cell rate of the radio system of the Unicom mobile
network in busy hour. G6 < 5%
G6 reflects the load situation, which is the congestion rate of the
signaling channel and the ratio of the cells having high congestion rate
of the voice channel, of the radio system of the Unicom GSM mobile
network, with the radio subsystem of the local network as the statistics
point.
G6 = Quantity of the overflow cells/ Total quantity of the cells × 100%
Definition of the overflow cell: The overflow cell is the cell having a
congestion rate of the signaling channel not less than 2% or the cell
having a congestion rate (including handover) of the voice channel in
busy hour not less than 5%.
Congestion rate of the signaling channel in busy hour = total overflow
times of the signaling channel in busy hour/total call attempt times of
the singling channel in busy hour × 100%
Congestion rate (including handover) of the voice channel in busy hour
= total overflow times (including handover) of the voice channel in
busy hour/total call attempt times of the voice channel in busy hour ×
100%
