How GPRS Works

Hi All,

   Lets have some details regarding GPRS Working, As we all know, It’s a Packet Switched Network, 

          

          In a GPRS Network, a user station doesn't occupy a dedicated path during an Internet connection. However, each end user station (e.g. mobile phone) is allocated several time slots out of 8 GSM/TDMA available time-slots for GPRS service. 

          
          Each time slot has a maximum capacity of 14.4 kbps, depending on how many time slots are allocated for the downlink (from a base station to a user station) and the uplink (from a user station to a base station), 

          
          GPRS devices are divided into multi-slot classes. A multi-slot class is often represented by the number of downlink and uplink slots. For example, Class 10 is also known as Class 4+2. While active slots indicate the maximum number of slots that can be allocated for both downlink and uplink in a specific class.

Class Types :-

• 2+1 (two slots for download + 1 for upload)
• 3+1 (three slots for download + 1 for upload)
• 4+1 (four slots for download + 1 for upload)

          GPRS is a mobile data upgrade to a GSM mobile phone network. This provides users with packet data services (similar to the Internet) using the GSM digital radio network. Each voice circuit in GSM transmits the speech on a secure 14kbps digital radio link between the mobile phone and a nearby GSM transceiver station.

          The GPRS service joins together multiple speech channels to provide higher bandwidth data connections for GPRS data users. The radio bandwidth remains the same, it is just shared between the voice users and the data users. The network operator has the choice of prioritizing one or the other.

           
          GPRS users will also benefit from being able to use GPRS while traveling as the GSM system should transparently hand over the GPRS connection from one base station to another.

GPRS Roaming - There are two type of GPRS Roaming

Home Network Roaming - Here all data is transmitted from wherever you connect to a GPRS network to your home GPRS network where it is connected to the Internet or your company LAN as if you were indeed in your home country.

Local Network Roaming - Data is just connected to a local Internet connection point and will be subject to local conditions for security and performance.

Radio Interface

           
          Each GSM radio transceiver uses Time Division Multiplexing to deliver eight voice circuits on one radio channel. Each radio site may have one or more transceivers to provide sufficient channels to end users (maximum numbers are limited by many factors including - operators radio license, interference with other nearby GSM cells, cost of equipment, capacity of radio site infrastructure, etc.)

          Each 14kbps channel may be shared by multiple 'connected' GPRS users (many users will be connected to the network but transmitting very little data). As a user's data requirements grow, they will use more of the available capacity within that timeslot, and then more available timeslots up to the maximum available or the maximum supported by their device.

In general the higher the data rate, the more power the mobile device will use and the shorter the battery life and the higher the transmitted RF power.

GPRS Tunneling Protocols will be updated soon….

Comments and Appreciations are most welcome.

ChEeEeEeErRrRrRs!!!

Telecom Tigers Team

telecomtigers@gmail.com

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