, . , .
GSM .
, MS BS Uplink ( MS BS). (AB - access burst) (RACH random access channel).
. 2.21.
, RACH, (FACCH Fast Associated Common Control Channel).
, (49 ) (39 ) MS BS. (GB - guard period), 68.25 . - 252 . . 2.22.
. 2.22.
. 2.22 (tail bits) , .
MS , BS, , . , 0 , 252 , .
.
GSM 35 . (63 ).
, , TA , 2.2.
(2.2)
TA ; DRT ,
(2.3)
v ; t = 1 = 48/13 [].