Hello My Friends …
I would like to understand one thing about PSC in 3G, according to people say that PSC is like BCCH in 2G and serves to identify cells. Except that in 2g, each cell has a BCCH different from the other cells. by 3g, cells attached to the same sector may have the same PSC. My question is:
How do we get to differentiate these cells? I need someone to help me understand this concept
It’s pretty much because in 2G its FDMA/TDMA and in 3G it’s CDMA so in 2G the system cannot deal too good with interference and in 3G it was designed to be ‘interfered’.
Let’s say one 2G cell has a bcch freq(arfcn) 280, if other neighbor cell radiates the same bcch freq in the same direction, then the signal will be interfered and then the quality will drop.
In 3G one freq(uarfcn) will be shared by all the stations and then you need something to differentiate them and you use PSC for this purpose(between some other technical reasons).
Now if you have one cell with PSC 1 and a neighbor cell with PSC 1 in the same freq(uarfcn) share the coverage area then, this will make a conflict.
In 3G if you have multi carriers to increase capacity you may deploy other carriers in other freqs(uarfcn) and to simplify PSC design process you tend to use the same PSC of the cell in the freq where you did the planning (mobility layer).
So regarding your question, you differentiate them because of the freq layer(uarfcn) , you may have uarfcn 1 and uarfcn 2 in one nodeb, and you have cell A, cell B and cell C in uarfcn 1 and cell D, cell E and cell F in uarfcn 2. Cell A and Cell D share the same antenna probably and are pointing to the same place so in this case Cell A and Cell D should have the same PSC.
That’s it