Number of channel in FDMA system

In an FDMA/FDD system, a single user occupies a single channel while the call is in process. The single-channel is two simplex channel that is frequency duplexed with a separation.

The number of channels that can be simultaneously supported in an FDMA system is given by : 

N =  B_t - 2 B_guard  /  B_c   

Where,

B_t  = Total spectrum allocation 

B_{guard  =}  Guard band allocated at the edge of the allocated spectrum

B_c = Channel bandwidth         

                    

For example:

B_t  = 10 MHz

B_guard = 10 KHz

B_c = 30 KHz

_{Find the number of channels available in the FDMA system?}

            N =  B_t - 2 B_guard  /  B_c 

  

              = 10 * 10⁶ – 2 * 10 * 10³ / 30 * 10³

          N  = 333

Each cellular carrier is allocated 333 channels.