. 6.23 - . , MSC. - ( BSC) ( BTS). MSC , . BSC , , . - , .
MSC . ³ . , GSM, , ISDN-, . , - 2048 /, Ѳ G.703. ( ) 125 , 32 , 64 /. GSM . , OSI, SS7. 2048 , . 2048 /.
- - . GSM . BSC 䳺 BTS -bis. , , 2048 /.
BTS
6.4.2.1.
䳺 , , -bis - . :
- ( ) ;
- , : , , () , ; : , (. combining) ; : , ;
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- ;
- , , BSC;
- ;
- .
( 16). . . 6.24 , . , .
6.23 -
, , ( ) . . RX, , RXFE. - /, GMSK, . , ( ). . , RXFE (. Receiver Front-End). , . RX - . , , .
, . . - ( ), , . . , , . . . .
6.24
, , (. combiner). , ᒺ , (. cavity combiner), . , , . , 5 dB .
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(. hybrid combiners), . - . , . . ó 7 dB.
GSM . , , 6 dB, , GSM900 ( 80 ) 20 .