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Cellular network,1st generation,2nd generation

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Inimitable Harish

Cellular network evolved gradually .Generations of computer network like 1st generation (1g) ,second generation (2g) evolved .Then came 3g ,4g, each time with increased speed and security

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Cellular Networks –First Generation- Second Generation Harish Kumar Upadhyay IT-A , Roll-31 ,s8
Cellular Networks  Cellular networks are wireless WAN that establish a connection between mobile users.  The network is comprised of many cells that typically cover 2 to 20 miles in area.  The communications are wireless within the cell only.  Many initial cellular network were predominantly analog because they were primarily targeted for voice users.  The use of cellular networks to support digital applications is increasing rapidly.
Cellular Concept  Another advantage of several small cells instead of a single transmitter=> frequency reuse: better efficiency  R cell radius and  D distance at which a frequency can be reused with acceptable interference
Cellular Network Organization  Areas divided into cells o Each served by its own antenna o Served by base station consisting of transmitter, receiver, and control unit o Band of frequencies allocated o Cells set up such that antennas of all neighbors are equidistant (hexagonal pattern)
Cellular Network Organization  Areas divided into cells o Each served by its own antenna o Served by base station consisting of transmitter, receiver, and control unit o Band of frequencies allocated o Cells set up such that antennas of all neighbors are equidistant (hexagonal pattern)
Frequency Reuse  Adjacent cells assigned different frequencies to avoid interference or crosstalk  Objective is to reuse frequency in nearby cells o 10 to 50 frequencies assigned to each cell o Transmission power controlled to limit power at that frequency escaping to adjacent cells o The issue is to determine how many cells must intervene between two cells using the same frequency
Cellular System Overview
Cellular Systems Terms  Base Transceiver Station (BTS) also known as Base Station (BS)– includes an antenna, a controller, and a number of receivers  Mobile telecommunications switching center (MTSC) also known as Mobile Switching Center(MSC)– connects calls between mobile units  Two types of channels available between mobile unit and BS o Control channels – used to exchange information having to do with setting up and maintaining calls o Traffic channels – carry voice or data connection between users
First Generation First-generation cellular networks were introduced in the 1980s are primarily intended for voice . These networks are very slow less than 1 kilobits per sec(kbps). The key idea of 1G cellular networks is that the geographical area is divided into cells ,each served by a base station.Cells are so small that frequency reuse is possible in the near by cells. They are primarily based on analog communications. Each phone has 32 bit serial number and 10 digit phone number in its PROM.
Security issues with 1G Analog cellular phones are insecure. Anyone with an all-band radio receiver can listen in to the conversation.There are also theft of airtime. A thief uses an all-band radio receiver that is connected to a comuter.This computer can record the 32-bit serial numbers and phone numbers of subscribers when calling The thieves can collect a large database by driving around and then can go into business bu reprogramming stolen phones and reselling them .
Second Generation Second generation cellular network introduced in 1980s ,are based on digital transmission. Primarily intended for voice they also support fax and email services at low bit-rate(8 to 9 kbps). The higher 2G systems use GSM(Global System For Mobile Communication) and low-tier system is intended for low-cost,low-power,low-mobility. Digital transmission offer several benefits overe analog :  Voice,data such as email and fax can be integrated into a single system. Better compression can lead to a better channel utilization. Error correction code can be used for better quality. Sophisticated encryption can be used.
Differences Between First and Second Generation Systems  Digital traffic channels – first-generation systems are almost purely analog; second-generation systems are digital  Encryption – all second generation systems provide encryption to prevent eavesdropping  Error detection and correction – second- generation digital traffic allows for detection and correction, giving clear voice reception  Channel access – second-generation systems allow channels to be dynamically shared by a number of users
REFERENCES :  www.wikipedia.org  McGrawHill :Mobile computing
Thank You  Open to questions ..

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Cellular network,1st generation,2nd generation

  • 1. Cellular Networks –First Generation- Second Generation Harish Kumar Upadhyay IT-A , Roll-31 ,s8
  • 2. Cellular Networks  Cellular networks are wireless WAN that establish a connection between mobile users.  The network is comprised of many cells that typically cover 2 to 20 miles in area.  The communications are wireless within the cell only.  Many initial cellular network were predominantly analog because they were primarily targeted for voice users.  The use of cellular networks to support digital applications is increasing rapidly.
  • 3. Cellular Concept  Another advantage of several small cells instead of a single transmitter=> frequency reuse: better efficiency  R cell radius and  D distance at which a frequency can be reused with acceptable interference
  • 4. Cellular Network Organization  Areas divided into cells o Each served by its own antenna o Served by base station consisting of transmitter, receiver, and control unit o Band of frequencies allocated o Cells set up such that antennas of all neighbors are equidistant (hexagonal pattern)
  • 5. Cellular Network Organization  Areas divided into cells o Each served by its own antenna o Served by base station consisting of transmitter, receiver, and control unit o Band of frequencies allocated o Cells set up such that antennas of all neighbors are equidistant (hexagonal pattern)
  • 6. Frequency Reuse  Adjacent cells assigned different frequencies to avoid interference or crosstalk  Objective is to reuse frequency in nearby cells o 10 to 50 frequencies assigned to each cell o Transmission power controlled to limit power at that frequency escaping to adjacent cells o The issue is to determine how many cells must intervene between two cells using the same frequency
  • 8. Cellular Systems Terms  Base Transceiver Station (BTS) also known as Base Station (BS)– includes an antenna, a controller, and a number of receivers  Mobile telecommunications switching center (MTSC) also known as Mobile Switching Center(MSC)– connects calls between mobile units  Two types of channels available between mobile unit and BS o Control channels – used to exchange information having to do with setting up and maintaining calls o Traffic channels – carry voice or data connection between users
  • 9. First Generation First-generation cellular networks were introduced in the 1980s are primarily intended for voice . These networks are very slow less than 1 kilobits per sec(kbps). The key idea of 1G cellular networks is that the geographical area is divided into cells ,each served by a base station.Cells are so small that frequency reuse is possible in the near by cells. They are primarily based on analog communications. Each phone has 32 bit serial number and 10 digit phone number in its PROM.
  • 10. Security issues with 1G Analog cellular phones are insecure. Anyone with an all-band radio receiver can listen in to the conversation.There are also theft of airtime. A thief uses an all-band radio receiver that is connected to a comuter.This computer can record the 32-bit serial numbers and phone numbers of subscribers when calling The thieves can collect a large database by driving around and then can go into business bu reprogramming stolen phones and reselling them .
  • 11. Second Generation Second generation cellular network introduced in 1980s ,are based on digital transmission. Primarily intended for voice they also support fax and email services at low bit-rate(8 to 9 kbps). The higher 2G systems use GSM(Global System For Mobile Communication) and low-tier system is intended for low-cost,low-power,low-mobility. Digital transmission offer several benefits overe analog :  Voice,data such as email and fax can be integrated into a single system. Better compression can lead to a better channel utilization. Error correction code can be used for better quality. Sophisticated encryption can be used.
  • 12. Differences Between First and Second Generation Systems  Digital traffic channels – first-generation systems are almost purely analog; second-generation systems are digital  Encryption – all second generation systems provide encryption to prevent eavesdropping  Error detection and correction – second- generation digital traffic allows for detection and correction, giving clear voice reception  Channel access – second-generation systems allow channels to be dynamically shared by a number of users
  • 13. REFERENCES :  www.wikipedia.org  McGrawHill :Mobile computing
  • 14. Thank You  Open to questions ..