GSM -The Birth And Growth
The birth of GSM can be traced back to early 1980s when a group of 26 European telecommunication administrators, called the Conference of European Posts and Telegraphs commissioned a study group named Groupe Special Mobile or better known as Global System for Mobile Communications. The group set out to design a system with a vision to provide good voice and speech quality, support international roaming enabling a person to use his mobile phone across countries without having to change his original number and support a range of products and value added services.
It was in 1989 that this standard was released by the European Standard and Technology Institute (ETSI). The first commercial GSM services were launched in parts of Europe in 1991 and the standard went to countries like Denmark, Finland, France, Germany, Italy, Portugal and Sweden in 1992. With the basic framework in place there was no stopping the technology. It was on a growth path as, in a years time, or by the end of 1993, there were more than one million subscribers on the European GSM Network with over 70 members of the GSM Association from 48 countries and 25 roaming agreements signed.
According to EMC world cellular database estimates, as on November 2002, there are 777.6 million members plying on GSM networks worldwide in some 165 countries. Thus, GSM, which was initially conceived for voice transfers only, now provides data services of various speeds depending on the level of standard being used, informs Nokia Networks director strategy Sanjay Bhasin. In fact todays second generation GSM networks deliver secure mobile voice and data services such as short messaging service (SMS) or text messaging and can offer data speed rates upto 9.6 kilobits per second (kbps). The members of the association working on the research and development of the standard, have been upgrading since. They have formed a path for migrating to the third generation or 3G standard which would basically ensure high speed data flow at the rate 384 Kbps.
After 2G GSM, operators can upgrade to General Packet Radio Service (GPRS) which enables networks offer an always-on, higher capacity (data flow at the rate of 40 Kbps, Internet-based content and packet-based data services and enables services such as colour Internet browsing, e-mail on the move, multimedia messaging among others. The next step in the migration path is wide band code division multiple access, which would enable extremely high speed data flow at the rate of 384 Kbps.
CDMA - The History And Geography
CDMA, meanwhile, made a delayed entry compared to GSM and was field tested for commercial use in 1991. The technology was launched commercially in Hong Kong in 1995. The US-based company Qualcomm, which patented CDMA, along with other telecommunications companies, was attracted to the technology because it enabled many simultaneous conversations, rather than the limited stop-and-go transmissions.
CDMA works by digitising multiple conversations, attaching a code known only to the sender and receiver, and then slicing the signals into bits and reassembling them, according to Qualcomm India director for technical marketing Rishi Dhingra. This standard today has around 138 million subscribers by the end of November 2002 as per EMC estimates.
Second generation CDMA standard is the cdmaOne family consisting of IS-95 CDMA Technologies IS95A and IS95B. IS-95A which is the first CDMA cellular standard provides voice services, and can provide circuit-switched data connections at 14.4 Kbps.
IS-95A was first deployed in September 1996 by Hutchison (HK). IS-95B, which is categorised as a 2.5G standard can offer 64 kbps packet-switched data, in addition to voice services. IS-95B was first deployed in September 1999 in Korea and has since been adopted by operators in Japan and Peru.
Third generation CDMA standards include CDMA2000 1X, also the worlds first IMT-2000 (3G) network to be commercially deployed in October 2000 and allows a data speed of 144 Kbps. The next frontier for 3G CDMA include CDMA 1x EVDO (evolution data optimised) and CDMA 1x EVDV (evolution data and voice).
CDMA2000 1xEV-DO delivers peak data speeds of 2.4Mbps in a bandwidth of 1.25 Mhz and supports applications such as MP3 transfers and video conferencing. CDMA2000 1xEV-DV provides integrated voice and simultaneous high-speed packet data multimedia services at speeds of upto 3.09 Mbps. Now players in either camp are aggressively marketing their respective technologies, fighting every inch for user mindshare.