Monday, December 30, 2002		Feature

WiLL CDMA pip GSM?

Nalin K. Rai

TELECOM genie has been uncorked for India in the real sense of terms exemplified by the fact that from just one or two cellular operators for a circle, the vie-for-pie has become so big that now four players have stepped into the ring.

With the advancements and evolution of technology the cellular operator also has been given an option to go in for either of the multiple technology platforms being sold by the developers. The multiple technology is not relegated to cellular operations only but the basic telephony is also seeing competitiveness in terms of technological preferences for the operations with the introduction of being the talk of the town.

For a cellular operator the option to choose is between CDMA and GSMA. A study in this regard to understand and provide the comparative advantages of the two technologies was conducted by INOMY, an Internet research company based at Delhi. The distinction between CDMA and GSMA is as under:

CDMA: Developed by Qualcomm for the US military, Code Division Multiple Access is a system that enables many users to share the same frequency band at the same time (called frequency spread). The CDMA is often compared with an airport transit lounge, where many persons speak in different languages. Each listener only understands one language, and therefore concentrates on his or her own conversation, ignoring the rest. But a roomful of people all talking at once soon becomes very loud. Everyone ends up trying to shout above the background noise, which just makes the problems worse. To prevent the chaos, CDMA codes are chosen so that they cancel each other out.

GSM: Short for Group Speciale Mobile or Global System for Mobile Communication, GSM allows eight simultaneous calls on the same radio frequency. As of the end of 1977, GSM service was available in more than 100 countries.

Scalability

CDMA can support more subscribers in a given cell area for a given bandwidth. In addition, the capacity of the system is not as rigid as in GSM. While, GSM cannot add more than a fixed number of subscribers in a cell, in a CDMA network the system can add on users, but with a rider of deterioration in the qualitativeness of the offer. Besides, the quality of sound is better in CDMA.

Radiation

For a mobile user, the battery life is the key factor in selection of a user and the power requirements in CDMA are lower than in GSM. This results in longer battery and low radiation risk for the user. As far as radiation levels are concerned, CDMA is the most harmless one among all existing technologies. Of course, it transmits microwaves while on standby mode, like other technologies do. However, CDMA technology checks 800 times per second its transmission level. Therefore, radiation level is 10 times less than AMPS and GSM. Another important thing to point out is that CDMA system transmits signals only when the user starts conversation.

In GSM, high mobile density areas lead to creation of Hotspots, where it is not possible to add more subscribers. This happens in areas like stock exchanges & financial districts. The CDMA-based network can handle this.

Indian scene

For India to become a knowledge house of the world, the archaic telecom standards need a jump of geometric proportions. CDMA-based WiLL could be a step in the right direction.

The Indian customer is price sensitive. The choice of technology will also be based on its ability to increase faster technological upgradation, and remove the technological obsolence. Hence a technology, which can support more customers at the same time, would be beneficial to the operator.

For a new basic telecom operator choosing CDMA based WiLL could be a better proposition as the current policy framework of Indian telephony is such that in case a basic service operator provides limited mobility then there are no spectrum costs to be paid to the government. There is therefore a possibility of providing mobile telephony services at prices equal to that of landline services. Hence basic service operators should take advantage of this policy and provide cheap limited CDMA-based WiLL services to the customers.

For the fourth cellular operator as well, the choice of CDMA could be a better economic choice as it supports more users than GSM, given the same resources. This means that a mobile service operator using CDMA would be able to support more customers than an operator using GSM. In cellular mobile services industry, a major portion of the costs to customers originates from the huge fixed costs borne by the operator. This cost reduces as the number of user increases, implying that more user means lesser call rates, which results in still more users. This obviously is a cycle that only a CDMA operator can support given its excess capacity as compared to a GSM one.