DFH is a type of SFH in which
no of Frequencies >= no of TRX
You dont have to assign a complete hopping group to each cell like in normal SFH.Its more of similar to BBH.Kindly note that its not necessarily used for cells which have little amount of TRX.Its equally beneficial for high configuration cells aswell.
Consider Frequency Band from 500-532(TCH) and 534-550(BCCH)ARFCN and a 4-TRX cell.
Lets just say that you are implementing DFH with
NO of Frequencies=No of TRX
So, you can have a scenario like:
Cell A= 534, 500,531,515
Cell B= 550, 504,512,518
Cell C= 546, 506,510,520
So, you see here the plan is just like BBH except for the fact that the whole BCCH TRX doesnt hop.Its more beneficial when you assign more frequencies than the no of TRXs.So, mostly for low configuration sites(2-TRX) , you can assign 4 frequencies and reap the advantage of DFH 🙂
I was curious about a statement of urs that
“most calls will be allocated on 2nd trx ” why do u say that? Has Alcatel removed the parameter “pref-mark” in your Release or you dont like playing with it(pm)? 😛
You are right about the SDCCH 🙂