Out of one billion, nearly 200 million customers jumped on the GSM bandwagon in the past 12 months alone. The next 12 will be far more exciting, when 400 million are expected to be added, with a distinct possibility of the second billionth customer arriving in less than five years!
IBM that took an early lead in the PC market was not the dominant player when PCs crossed the billion mark in 2002 Dell was. Similarly, Motorola that pioneered the mobile phone instrument is not the dominant player today. For years, it has been Nokia. Of course, GSM is not the only technology that mobile phones use. We have the older analog cellular phones in US and CDMA phones in Korea, China, India and US. There could be other competing technologies, including those that use Wi-Fi. But for the past decade or so, GSM has been the dominant player.
It was in 1982 that the Group Special Mobile was originally introduced in Europe. For nearly a decade, many country-specific GSM systems existed one in Germany, one in UK and one in Italy etc. With a view to have a unified system that provided global roaming, good speech quality, fax support and ISDN compatibility, the next version of GSM the Global System for Mobile communications was launched in 1991-92.
Interestingly, GSM bet on digital technology with its faith in the performance of compression algorithms and continued improvement in quality through better performance of digital signal processing. Both, the US in its AMPS system and UK in its TACS system stayed with the analog system that fell by the wayside over the years. Through the effort of a group of professionals working for different companies located in multiple countries, GSM also is the success of standards-based technology, if the 8,000+ pages of GSM Standard Recommendations are any guide.
Technically, GSM uses 890-915 MHz frequency spectrum for up-linking and 935-960 MHz for down-linking; there are other systems including PCS 1900 that use other frequencies today. Using a unique International Mobile Equipment Identification and a unique International Mobile Subscriber Identity, GSM provides a secure yet convenient way of handling subscriber identity (known to users as SIM card identity and password protection). Naturally, call identification is built into GSM an afterthought in landline telephony.
Using Home Location Register, Visitor Location Register, Equipment Identity Register and Authentication Center, GSM handles roaming that lets users have not just local mobility but global mobility as well. The various registers can be implemented as distributed or centralised databases depending on the need. Using 20 millisecond samples encoded as 260 bits and a three-part CRC for error correction, the payload of 456 bits translates to 22.8 Kbps for high quality speech.
Using multi-path equalisation, GSM handles echo cancellation; using sophisticated threshold detection, GSM handles seamless handover as the user moves from one cell to another. Realising the fact that the user is silent for nearly 50 per cent of the time, GSM manages power really well leading to longer battery life.
GSM has also seen several value-added features introduced over the years; SMS (short message service) is a 160-byte long two-way messaging system that practically wiped out the pager market in India; SMS is an excellent add-on to basic telephony. Ringtones that account for $2 billion+ business every year is another runaway success. Mobile information services, such as Jet Mobile from Jet Airways and mobile banking from ICICI Bank, are other interesting examples. The day is not far when institutions like the IIIT-B will provide entrance exam results and course grades through GSM phones!
India saw the introduction of GSM phones in Kolkata in March 1997. It has a base of 20 million+ GSM phones today. This country saw the addition of more than 10 million phones in year 2003 alone. Globally, Asia alone added 70 million GSM phones in year 2003, with Europe accounting for another 42 million. Truly the Age of Asia has arrived! Today, GSM is used in nearly all the countries covered under United Nations. In India, there is GSM coverage across all states including Jammu and Kashmir and the North-east.
A brilliant past and a bright future truly characterises the soul of GSM.
The author is director of Indian Institute of Information Technology, Bangalore. These are his personal views. He can be reached at Sadagopan@sadagopan.com