Zte ZXG10-OB06, Техническое руководство

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ZXG10-OB06 (V1.0) Integrated Outdoor GSM Base Station Technical Manual
78 Confidential and Proprietary Information of ZTE CORPORATION
propagation environment, it is difficult to offer coverage with a radius
greater than 35 km. However, in some special propagation conditions, it is
possible to cover a radius greater than 35 km. The conditions may include
low propagation loss at areas like coasts, deserts and grasslands. Under
such conditions, ultra-distance coverage is possible with the help of BTS of
high-power output and high-gain antenna.
At ultra-distance, the time of arrival of a signal at the BTS takes two time
slots, as shown in Figure 63. Thus, a dedicated control channel and a
service channel can be two physical channels, namely, two consecutive
time slots.
F
I G U R E
6 3 – T
I M E
D
E L A Y
R
E L A T I O N S H I P
0 0 1 1
General air delay-63
0 6 7 1 2
2 3 4 5 6 7
3 4 5 0 7 6 5
OB06
transmitting
63-bit transmitting in advance
MS
transmitting
When BTS uses two time slots to process the data of one subscriber, the
second time slot is termed as the extended channel as shown in Figure 64.
F
I G U R E
6 4 – O B 0 6 S
I G N A L
P
R O C E S S I N G
2 3 4 5 6 7 2
0 0 1 1
Frame
Extended
channels
Figure 65 shows the carrier frequency after channel expansion. Originally,
a TRX can provide eight physical channels. After channel expansion, one
carrier frequency has four physical channels, while half-reduce the carrier
frequency capacity.