Question

A TDMA/FDD based GSM cellular system a band of 25 MHz for the forward link, which is divided into radio channels of 200 kHz each. If 8 speech channels (time slots) are supported on a single radio channel, then the maximum number of simultaneous subscribers that can be accommodated in the GSM system will be (Assume no guard band)

• A. 1000
• B. 500
• C. 125
• D. 250

Answer 1

The correct option is A 1000

Totala bandwidth, $B_t=25MHz$

Bandwidth of each radio channel, $B_c=200kHz$

Number of time slots for each radio channel, $m=8$

Total number of radio channels possible $=\frac{25\times 1000}{200}=125$

Maximum number of simultaneously users $=125\times 8=1000$