BCF = cxontrol of the site
BTS is the a cell within the site there can be 1, 2 or 3 BTS, normally 3.
You can lock a BTS down and it will not effect the other BTS or the BCF. Lock the BCF down and you stop all BTS transmissions from the site.
A BCF has a number say 13
Cell 1 is called BTS 13, , Cell2 BTS 14 and Cell 3 BTS 15 for MML reasons to be able to distingush between the BTS’s on the site (BCF) so BCF13, BTS14 refers to the site and the 2nd BTS