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GSM and 3G
GSM And 3G
GSM
Global System for Mobile communications (GSM) is basically an international standard of cellular service. Originally, the acronym GSM stood for Groupe Spécial Mobile, a group formed by the Conference of European Posts and Telegraphs (CEPT) in 1982 to research the merits of a European standard for mobile telecommunications. Commercial service using the GSM system did not actually start until 1991. Instead of using analog service, GSM was developed as a digital system using TDMA technology. Using TDMA, a narrow band that is 30 kHz wide and 6.7 milliseconds long is split time-wise into three time slots. Narrow band means channels in the traditional sense. Each conversation gets the radio for one-third of the time. This is possible because voice data that has been converted to digital information is compressed so that it takes up significantly less transmission space. Therefore, TDMA has three times the capacity of an analog system using the same number of channels. TDMA splits a frequency into time slots and is the access method used by GSM. GSM systems provide a number of useful and popular features:
1) Uses encryption to make phone calls more secure
2) Data networking
4) Short Message Service SMS for text messages and paging
5) Call forwarding
6) Caller ID
7) Call waiting
8) Multi-party conferencing
GSM operates in the 900 MHz band (890 MHz- 960 MHz) in Europe and Asia and in the 1900 MHz (sometimes referred to as 1.9 GHz) band in the United States. The incredible growth of GSM is a big part of why the acronym is now commonly thought of as standing for the Global System for Mobile communications.
As a technology, GSM continues to evolve, with high-bandwidth services becoming a reality for the current 2nd Generation technologies. The development path into the 3rd Generation is clearly mapped out and brings with it possibilities for new age data and multi-media applications.The GSM network is growing, with wireless, satellite and cordless systems offering greatly expanded services, including high speed, multi-media data services, in-built support for parallel usage of such services and seamless connection with the Internet and wire-line networks. This will see the true convergence between various communications means and networks becoming a reality which is nothing but 3G.
3G or 3rd Generation
3rd Generation is the generic term used for the next generation of mobile communications systems. 3G systems provide enhanced services such as voice, text and data .The GSM Association's vision of 3G is based on today's GSM standard, but evolved, extended and enhanced to include an additional radio air interface, better suited for high speed and multimedia data services. This system will enable users of current 2nd Generation GSM wireless networks to migrate easily to the new 3rd Generation services, with minimal disruption.
The demand for multimedia services, combined with greater pressure on time and the growing dependence on mobility, will cause a huge demand for mobile access to these services –anytime, anywhere. Thus the logical next step would be for the various communications industries to converge for the provision of broadband mobile communications.
Primary among 3G objectives is the availability of services anytime and anywhere irrespective of media or access technology. While mobile users are currently served by a wide range of different networks and standards in many different parts of the radio frequency spectrum, this next generation will technically integrate a variety of delivery platforms from fibre optics to satellites to provide a seamless service to the end user. By combining fixed and wireless services, 3G will provide universal accessibility and fixed network mobility, with a quality and integrity comparable to that of fixed networks while achieving higher spectrum efficiency than existing mobile systems. The wireless segment with the greatest potential, given its current rate of growth, is undoubtedly cellular.
Where the first generation of cellular services offered a simple analogue channel of very limited features, the generation after provided an improved digital platform with more advanced features but still remained very limited in terms of bandwidth. These second generation (2G) systems, as typified by the Global System for Mobile Communications (GSM) family that includes GSM 900/1800 have proven to be highly successful and are the most prolific standards currently in use around the world. Though these 2G systems with their digital capabilities are a vast improvement over their analogue predecessors, they are still restricted to mainly voice transmissions by their fixed bandwidth. Most GSM systems can support data speeds of up to 9.6 kilobytes per second, though recent advances have pushed the data rate higher . While sufficient for non-time essential, bursty services such as short text messages (SMS), it is still too slow to support applications like real-time audio/video or high speed IP connections to the Internet. The development of well-matched next-generation standards will diminish, if not eradicate this problem altogether.
The common platforms will also provide convenience for users, greater economies of scale for manufacturers and in turn lower terminal and network infrastructure costs for operators. All of which may eventually lead to lower costs for consumers. To provide universal access to mobile services, 3G planners envision the various wireless delivery systems will be linked to fixed networks and will converge to form a hierarchical structure of discontinuous overlaid radio cells. These will range from picocells providing in-building coverage, to larger microcells over a macrocell structure, with wide area coverage provided by global satellites. The terrestrial based systems with their moderate to small sized cells will provide high capacity through their high spectrum reuse, but given the limits to terrestrial based global coverage due to population patterns and economies of scale, satellite based systems will be used in a complementary mode.
Even though satellites have relatively lower capacity in terms of the numbers of users per unit area, they have the advantage of fast deployment, flexible use, and ubiquitous global coverage to handheld personal units in all places at all times.
This hierarchical cell structure will enable gradated support of a wide range of services from voice and low-rate data to high-rate multimedia services with up to 144 Kbps in vehicular, 384 Kbps in outdoor to indoor.
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GSM and 3G
GSM And 3G
GSM
Global System for Mobile communications (GSM) is basically an international standard of cellular service. Originally, the acronym GSM stood for Groupe Spécial Mobile, a group formed by the Conference of European Posts and Telegraphs (CEPT) in 1982 to research the merits of a European standard for mobile telecommunications. Commercial service using the GSM system did not actually start until 1991. Instead of using analog service, GSM was developed as a digital system using TDMA technology. Using TDMA, a narrow band that is 30 kHz wide and 6.7 milliseconds long is split time-wise into three time slots. Narrow band means channels in the traditional sense. Each conversation gets the radio for one-third of the time. This is possible because voice data that has been converted to digital information is compressed so that it takes up significantly less transmission space. Therefore, TDMA has three times the capacity of an analog system using the same number of channels. TDMA splits a frequency into time slots and is the access method used by GSM. GSM systems provide a number of useful and popular features:
1) Uses encryption to make phone calls more secure
2) Data networking
4) Short Message Service SMS for text messages and paging
5) Call forwarding
6) Caller ID
7) Call waiting
8) Multi-party conferencing
GSM operates in the 900 MHz band (890 MHz- 960 MHz) in Europe and Asia and in the 1900 MHz (sometimes referred to as 1.9 GHz) band in the United States. The incredible growth of GSM is a big part of why the acronym is now commonly thought of as standing for the Global System for Mobile communications.
As a technology, GSM continues to evolve, with high-bandwidth services becoming a reality for the current 2nd Generation technologies. The development path into the 3rd Generation is clearly mapped out and brings with it possibilities for new age data and multi-media applications.The GSM network is growing, with wireless, satellite and cordless systems offering greatly expanded services, including high speed, multi-media data services, in-built support for parallel usage of such services and seamless connection with the Internet and wire-line networks. This will see the true convergence between various communications means and networks becoming a reality which is nothing but 3G.
3G or 3rd Generation
3rd Generation is the generic term used for the next generation of mobile communications systems. 3G systems provide enhanced services such as voice, text and data .The GSM Association's vision of 3G is based on today's GSM standard, but evolved, extended and enhanced to include an additional radio air interface, better suited for high speed and multimedia data services. This system will enable users of current 2nd Generation GSM wireless networks to migrate easily to the new 3rd Generation services, with minimal disruption.
The demand for multimedia services, combined with greater pressure on time and the growing dependence on mobility, will cause a huge demand for mobile access to these services –anytime, anywhere. Thus the logical next step would be for the various communications industries to converge for the provision of broadband mobile communications.
Primary among 3G objectives is the availability of services anytime and anywhere irrespective of media or access technology. While mobile users are currently served by a wide range of different networks and standards in many different parts of the radio frequency spectrum, this next generation will technically integrate a variety of delivery platforms from fibre optics to satellites to provide a seamless service to the end user. By combining fixed and wireless services, 3G will provide universal accessibility and fixed network mobility, with a quality and integrity comparable to that of fixed networks while achieving higher spectrum efficiency than existing mobile systems. The wireless segment with the greatest potential, given its current rate of growth, is undoubtedly cellular.
Where the first generation of cellular services offered a simple analogue channel of very limited features, the generation after provided an improved digital platform with more advanced features but still remained very limited in terms of bandwidth. These second generation (2G) systems, as typified by the Global System for Mobile Communications (GSM) family that includes GSM 900/1800 have proven to be highly successful and are the most prolific standards currently in use around the world. Though these 2G systems with their digital capabilities are a vast improvement over their analogue predecessors, they are still restricted to mainly voice transmissions by their fixed bandwidth. Most GSM systems can support data speeds of up to 9.6 kilobytes per second, though recent advances have pushed the data rate higher . While sufficient for non-time essential, bursty services such as short text messages (SMS), it is still too slow to support applications like real-time audio/video or high speed IP connections to the Internet. The development of well-matched next-generation standards will diminish, if not eradicate this problem altogether.
The common platforms will also provide convenience for users, greater economies of scale for manufacturers and in turn lower terminal and network infrastructure costs for operators. All of which may eventually lead to lower costs for consumers. To provide universal access to mobile services, 3G planners envision the various wireless delivery systems will be linked to fixed networks and will converge to form a hierarchical structure of discontinuous overlaid radio cells. These will range from picocells providing in-building coverage, to larger microcells over a macrocell structure, with wide area coverage provided by global satellites. The terrestrial based systems with their moderate to small sized cells will provide high capacity through their high spectrum reuse, but given the limits to terrestrial based global coverage due to population patterns and economies of scale, satellite based systems will be used in a complementary mode.
Even though satellites have relatively lower capacity in terms of the numbers of users per unit area, they have the advantage of fast deployment, flexible use, and ubiquitous global coverage to handheld personal units in all places at all times.
This hierarchical cell structure will enable gradated support of a wide range of services from voice and low-rate data to high-rate multimedia services with up to 144 Kbps in vehicular, 384 Kbps in outdoor to indoor.
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