To: JGoren who wrote (3204 ) 9/19/2000 10:37:56 PM From: SKIP PAUL Respond to of 197472 203.197.64.220 :90/Scripts/ettimes_ks.exe?method=mainContentFrame&docid=71145&links=CDMA&database=0&url=http%3A%2F%2Fwww%2Eeconomictimes%2Ecom%2Ftoday%2F14edit05%2Ehtm&title=Sep%2014%202000%20EDITORIAL%20Choice%20for%20rural%20application%3A%20WLL%20on%20CDMA%20&attachto=names=EconomicTimes&showType=HTML&autoSuggest=ON&checksum=&fieldStr=&fieldBool= -------------------------------------------------------------------------------- Choice for rural application: WLL on CDMA Rajendra Prabhu THE HIGH cost of installing village telephones has been a major obstacle in extending the telephone network in rural areas. This could well be a thing of the past if, as the Department of Telecom believes, the problem can indeed be solved by moving over to Wireless Local Loop technology. The more difficult task before DoT, however, is in deciding between the two technologies used in wireless access — code division multiple access and time division multiple access. After two years of rigorous tests between different technologies, the DoT chose wireless local loop on the CDMA platform. The DoT plan was to extend the reach of its indigenously designed 2000 to 10,000 line C-DoT exchanges in suburban areas and small towns by stringing on the wireless line on them reaching out to a radius of 65 km, offering limited mobility within an area of 25000 sq km. Between the two WLL technologies, GSM and CDMA, the latter was chosen for both cost and operational reasons. After floating tenders for a massive WLL based rural telephone, the DoT is now having second thoughts, not on technology as such, but on the plea that world over the migration of wireless telephony to Third Generation has begun. The International Telecommunication Union approved the 3G migration and allotted three different frequencies for this purpose only two months back. The third generation wireless involves full integration of voice, data and video on the wireless mobile telephone. Within the DoT the debate is on. As 3G is going to be next thing coming, why don’t we have 3G based new equipment rather than go for the WLL based on CDMA? While the DoT’s alertness to changing demands of technology is commendable, the debate itself seems a little unrealistic. For one thing, even in the most advanced countries, the 3G networks are not expected before 2003. In the last ITU conference in October last, several experts of Lucent, Alcatel and Siemens told this correspondent that the idea of a single system to carry both voice, data and video will not be operational before the next ITU conference comes around, that is 2003. Japan’s NTT DoCoMo is the only operator who has announced a firm time table for migration. That too has put 2003 as the date to start 3G services. India’s villages do need a telephone line that could carry fax and data and provide at least limited mobility. The cellular mobile telephone operators are offering telephone services to some villages already at a comparatively cheap rate on their GSM platform. It is mostly voice carriage though WAP (wireless application protocol for data) is also awaiting implementation in urban areas. But the DoT testing of CDMA, TDMA (the latter on the GSM standard) had clearly established the CDMA as the best in from all angles. CDMA coverage is twice that of GSM and capacity two to four times. While GSM channels are 22 in CDMA it is 125 from the same base switch. Spectral efficiency for CDMA is stated to be four times that of GSM. Voice quality is better as it could work on 14.4 kbps as against the 9.6 kbps for GSM. Even considering a future scenario of 3G, the CDMA requires only software upgrade and no change in base switches as 850 Mhz is one of the three frequencies for 3G, while GSM was working on 900 MHz frequency not suitable for 3G. The fixed terminal costs are Rs 14,000 for CDMA, Rs 20,000 for GSM and total equipment costs also tilt the choice in favour of CDMA by as much as Rs 6000 less for a subscriber base of 3500. A major factor that favoured the choice was the ability of CDMA stations to work with power from solar panels. Operational costs differed with CDMA station costing Rs 27 lakh per month with 25 employees while the GSM came to Rs 57 lakh requiring 40 employees. The more recent CDMA technology has now become the preferred choice worldwide with 34 million subscribers in Asia-Pacific alone. All the basic operators in the private sector in this country have chosen CDMA for their own urban WLL subscribers. As a result, equipment makers in India too have now the base to manufacture the CDMA based items. All these suggest that wisdom seems to lie in going for the CDMA based rural telephony using WLL and then upgrade it to 3G as and when that becomes universal. That this would offer some stiff competition to the cellular mobile when it comes to interior villages, is a different issue. Perhaps such a competition should be welcome.