Hey siva,
You know the bandwidth of the GSMK filter is 67.5 and the output of the mobile is at 270.333 .Divide 270 by 67.5 you get 4 i,e you would need 4 channels in UL and 4 channels in DL thus giving u 8 timeslot per TRX.
Regards
M.Thyagarajan
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