Gsm Specification & Air Interface
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WHAT IS GSM????
GSM: GSM (Global System for Mobile Communications: originally from Groupe Spécial Mobile) is the most popular standard for mobile telephone systems in the world. The GSM Association, its promoting industry trade organization of mobile phone carriers and manufacturers, estimates that 80% of the global mobile market uses the standard.
GSM Specifications-I
RF Spectrum
GSM 900
1. Mobile to BTS (uplink): 890-915 MHz
2. BTS to Mobile (downlink):935-960 MHz
3. Bandwidth: 2* 25 MHz
GSM 1800
1. Mobile to BTS (uplink): 1710-1785 MHz
2. BTS to Mobile (downlink) 1805-1880 MHz
3. Bandwidth: 2* 75 MHz
GSM Specification-II
1. Carrier Separation : 200 KHz
2. Duplex Distance : 45 MHz
3. No. of RF carriers : 124
4. Access Method : TDMA/FDMA
5. Modulation Method: GMSK
6. Modulation data rate: 270.833 Kbps
ADVANTAGES OF GSM:
1. GSM uses radio frequencies efficiently & due to the digital radio path the system tolerates more intercellular disturbances.
2. The average quality of speech achieved is better than in existing analogue systems.
3. Data transmission is supported throughout the system.
4. Speech is encrypted & subscriber information security is guaranteed.
5. Due to the ISDN compatibility, new services are offered compared to analogue systems.
6. International roaming is technically possible within all the countries concerned.
7. The large market toughens the competition & lowers the prices both for investments & usages.
GSM SPECIFICATIONS
The main idea behind the GSM specifications is to define several open interfaces which then are limiting certain parts of the GSM system. Because of this interface, openness the operator maintaining the network may obtain different parts of the network from different GSM
WHAT IS GSM????
GSM: GSM (Global System for Mobile Communications: originally from Groupe Spécial Mobile) is the most popular standard for mobile telephone systems in the world. The GSM Association, its promoting industry trade organization of mobile phone carriers and manufacturers, estimates that 80% of the global mobile market uses the standard.
GSM Specifications-I
RF Spectrum
GSM 900
1. Mobile to BTS (uplink): 890-915 MHz
2. BTS to Mobile (downlink):935-960 MHz
3. Bandwidth: 2* 25 MHz
GSM 1800
1. Mobile to BTS (uplink): 1710-1785 MHz
2. BTS to Mobile (downlink) 1805-1880 MHz
3. Bandwidth: 2* 75 MHz
GSM Specification-II
1. Carrier Separation : 200 KHz
2. Duplex Distance : 45 MHz
3. No. of RF carriers : 124
4. Access Method : TDMA/FDMA
5. Modulation Method: GMSK
6. Modulation data rate: 270.833 Kbps
ADVANTAGES OF GSM:
1. GSM uses radio frequencies efficiently & due to the digital radio path the system tolerates more intercellular disturbances.
2. The average quality of speech achieved is better than in existing analogue systems.
3. Data transmission is supported throughout the system.
4. Speech is encrypted & subscriber information security is guaranteed.
5. Due to the ISDN compatibility, new services are offered compared to analogue systems.
6. International roaming is technically possible within all the countries concerned.
7. The large market toughens the competition & lowers the prices both for investments & usages.
GSM SPECIFICATIONS
The main idea behind the GSM specifications is to define several open interfaces which then are limiting certain parts of the GSM system. Because of this interface, openness the operator maintaining the network may obtain different parts of the network from different GSM