GSM Mohammad AL-adwan

Introduction GSM (Global System for Mobile Communications, originally Groupe Spécial Mobile), is a standard developed by (ETSI) to describe protocols for second generation (2G) digital cellular networks used by mobile phones.

1 st Generation First use in Tokyo in 1979 Analog System FDMA Bw = 40 MHz between MHz 832 channels 10 kbps Voice Only

2nd Generation First use at end of 1980s Digital System TDMA / CDMA 384 kbps Voice and Data

3rd Generation First use in 2001 Digital System WCDMA Downlink : 14.4 Mbps || Uplink : 5.8 Mbps Voice and Data

4th Generation Started in 2010 but used in 2013 Digital System WCDMA Downlink : 1 Gbps || Uplink : 0.5 Gbps Voice and Data

1 st Look MSC BS MS BS

1 st Look MSC Mobile Switching Center is the head of the cellular communications process. Any provider must have one MSC at least.

1 st Look MSC BS MS BS

1 st Look BS Base Stations function is to propagate and receive EM waves. GSM is a cellular network, which means that cell phones connect to it by searching for cells in the immediate vicinity. There are five different cell sizes in a GSM network—macro, micro, pico, femto, and umbrella cells.

1 st Look BS

Some more base station equipment Typical macro cell Typical micro cell

1 st Look MSC BS MS BS

1 st Look MS Mobile Stations are the mobile phones. In general any device have a GSM module and SIM card (Subscriber Identity Module).

Call Flow [ 2 MS’s in the same cell ]

Call Flow [ 2 MS’s in different cells ] MSC

Challenges of GSM 1.Co-Channel Interference 2.Adjacent Channel Interference

Co-Channel Interference Frequency Reuse

Co-Channel Interference

Adjacent Channel Interference

Frequency Bands In Jordan

Any Question ?? Thank You