11-08-2012, 12:37 PM
WIRELESS NETWORKS: EVOLUTION FROM 1G TO 4G
[attachment=31096]
First Generation Analog Wireless Cellular System
Transmit only analog voice information
Use FDMA Access Technology which uses 30 KHz channels of spectrum each carrying one Telephone ckt.
Types of Analog Cellular System :
1. AMPS (Advance Mobile Phone Service) :
-First introduced in U.S.
- 30 KHz radio channel,824MHz to 849 MHz Uplink freq. and 869 to 894 MHz downlink, Provide 832 channels
2. TACS (Totol Access Communication System):
- First Introduced in U.K. in 1985,Use 25 KHz radio channel
- 890 to 915 MHz uplink and 869 to 894 MHz downlink freq.
3. NMT ( Nordic Mobile Telephone) :
- Developed by telecommunication administrations of Nordic countries
- NMT-450 use lower frequency(450 MHz) and high Transmitting power
- NMT-900 use higher frequency and low transmitting power
- Radio channel is of 25 KHz
4. NAMPS ( Narrowband AMPS ) :
- Introduced by Motorola in 1991
- Use 10 KHz BW for radio channel
2G Digital Wireless System
It use digital radio signals
1G and 2G both use digital signaling to connect radio tower to rest of telephone system
Main 2G technologies are TDMA,CDMA and GSM
GSM utilizes wider band(200 KHz) carrier frequencies and each support 8 time slots
Advantages :
1. Due to digital error checking, sound quality is increased
2. Allowed digital data services like SMS and email
3. Digital system emit less power so more cells could be placed in same amount of space
Disadvantages :
1. Weaker digital signal will not reach a cell tower in less populous area
2. Under worse condition digital has occasional dropout
2.5G Wireless Mobile Technology
It enable high speed data transfer over upgraded existing 2G network by sending data as packets at very fast speed
2.5G use two technology
1. GPRS ( General Packet Radio Service ):
- It is packet linked technology that enable high-speed wireless internet
- Implemented by adding new packet data nodes and upgrading existing node to provide routing path for packet data between mobile and gateway node
Third Generation System
ITU has defined the demands for third generation mobile network with IMT-2000 standard. System that fulfils IMT-2000 standard is UMTS
3G networks are wide area cellular telephone network evolved to incorporate high speed internet access
3G uses 0.5 MHz channel carrier width to deliver higher data rates and increased capacity
4G Wireless Technology
This technology is expected to be available by 2010
4G being developed with following objectives
- Speeds up to 50 times higher than 3G
- To accomplish multi-service capacity integrating all the mobile technologies that exist
- This network must be available to users ant time, anywhere
- Low bit cost is essential where high volume of data are transmitted
To be able to use 4G mobile networks, mobile terminal must be able to choose from available wireless networks the one to use with specific service
Terminal mobility is key factor to the success of 4G network
CONCLUSION
The explosive growth of mobile wireless usage and ever increasing need for high-speed data services accelerated the need for the deployment of 3G technologies.
[attachment=31096]
First Generation Analog Wireless Cellular System
Transmit only analog voice information
Use FDMA Access Technology which uses 30 KHz channels of spectrum each carrying one Telephone ckt.
Types of Analog Cellular System :
1. AMPS (Advance Mobile Phone Service) :
-First introduced in U.S.
- 30 KHz radio channel,824MHz to 849 MHz Uplink freq. and 869 to 894 MHz downlink, Provide 832 channels
2. TACS (Totol Access Communication System):
- First Introduced in U.K. in 1985,Use 25 KHz radio channel
- 890 to 915 MHz uplink and 869 to 894 MHz downlink freq.
3. NMT ( Nordic Mobile Telephone) :
- Developed by telecommunication administrations of Nordic countries
- NMT-450 use lower frequency(450 MHz) and high Transmitting power
- NMT-900 use higher frequency and low transmitting power
- Radio channel is of 25 KHz
4. NAMPS ( Narrowband AMPS ) :
- Introduced by Motorola in 1991
- Use 10 KHz BW for radio channel
2G Digital Wireless System
It use digital radio signals
1G and 2G both use digital signaling to connect radio tower to rest of telephone system
Main 2G technologies are TDMA,CDMA and GSM
GSM utilizes wider band(200 KHz) carrier frequencies and each support 8 time slots
Advantages :
1. Due to digital error checking, sound quality is increased
2. Allowed digital data services like SMS and email
3. Digital system emit less power so more cells could be placed in same amount of space
Disadvantages :
1. Weaker digital signal will not reach a cell tower in less populous area
2. Under worse condition digital has occasional dropout
2.5G Wireless Mobile Technology
It enable high speed data transfer over upgraded existing 2G network by sending data as packets at very fast speed
2.5G use two technology
1. GPRS ( General Packet Radio Service ):
- It is packet linked technology that enable high-speed wireless internet
- Implemented by adding new packet data nodes and upgrading existing node to provide routing path for packet data between mobile and gateway node
Third Generation System
ITU has defined the demands for third generation mobile network with IMT-2000 standard. System that fulfils IMT-2000 standard is UMTS
3G networks are wide area cellular telephone network evolved to incorporate high speed internet access
3G uses 0.5 MHz channel carrier width to deliver higher data rates and increased capacity
4G Wireless Technology
This technology is expected to be available by 2010
4G being developed with following objectives
- Speeds up to 50 times higher than 3G
- To accomplish multi-service capacity integrating all the mobile technologies that exist
- This network must be available to users ant time, anywhere
- Low bit cost is essential where high volume of data are transmitted
To be able to use 4G mobile networks, mobile terminal must be able to choose from available wireless networks the one to use with specific service
Terminal mobility is key factor to the success of 4G network
CONCLUSION
The explosive growth of mobile wireless usage and ever increasing need for high-speed data services accelerated the need for the deployment of 3G technologies.