GSM: Frequency Reusage
Dear BATMAN
If we are dealing with GSM system any GSM channel has 200KHZ bandwidth, with a separation of 10 KHZ you can presume any channel has 210Khz bandwidth, It is not clear that 12MHz bandwidth is given for both uplink and downlink or it is just given for one of them. If it is the first case there should be a big gaurd band between 2 portion of bandwidth in standard 45MHZ is concidered between uplink and downlink but in your scenario I suggest to presume that for uplink you are using from the beginning frequnacy and for downlink you must you from end of available bandwidth beacuse downlink frequency must be higher that uplink. So generally 12MHz should be divided by 2, for Uplink and downlink then any 6mhz bandwidth is divided by 210Khz which brings you 28.5 channels for uplink and downlink. then you can multiply it by 8 and it is all the available channels but remember that form 8 time slot some of them are used for signaling.
If you have 19 cell cluster because you have 360 cells then you have 360/19 clusters which equals to 18.5 one, all the available channels in your case 28.5 is divided between 19 cells and then you can reuse all the available channels in these 18.5 clusters.