ZTE Corporation ZXG-BTS2 Manuale Utente
ZXG10-BTS (V2.9) Technical Manual
90
Confidential and Proprietary Information of ZTE CORPORATION
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I G U R E
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D
E L A Y
R
E L A T I O N S
0
0
1
1
Total Air Delay-63
0
6
7
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7
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0
7
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BTS to
MS to
Send out 63 bits ahead
When the BTS uses two timeslots to process the data of one subscriber,
the second timeslot is called the extended channel, a shown in Figure 73.
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E
X T E N D E D
C
H A N N E L
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7
2
0
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1
1
Frame
Extended Channel
Figure 74 shows an extended carrier. As shown in the figure, the original
TRX can provide eight physical channels, but the number of physical
TRX can provide eight physical channels, but the number of physical
channels is reduced by half after the channels are extended.
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I G U R E
7 4
T
H E
A
C T U A L
N
U M B E R O F
P
H Y S I C A L
C
H A N N E L S I N A
C
A R R I E R
0
0
3
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1
1
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7
O riginal T RX
E xtended
C hannel
TRX
With extended channels, the coverage of the BTS is theoretically up to a
radius of 120 km, and the maximum time advance is 219.Due to the
relatively large transmission loss and the problems in uplink and downlink
relatively large transmission loss and the problems in uplink and downlink
balancing, the actual coverage radius in the GSM900 is less than 120 km.