Eyes on S-band

Eyes on S-band

Recently, four former Indian Space Research Organisation (ISRO) scientists, including a past chairperson, were blacklisted for their role in the controversial Antrix- Devas deal. They had sold part of the S-band spectrum at a low price to Devas Multimedia Private Ltd without informing the Space Commission. This spectrum was given to ISRO by Wireless Planning Commission (WPC) under the Department of Telecommunications for mobile satellite services (MSS). It was to be utilised for satellite phones.

But even years after it was given to ISRO, the band has remained unutilised. Mobile operators have been lobbying for part of this S-band (2.5 – 2.69 GHz) as an extension for 3G services. They say S-band is a limited natural resource available to the country and it should not be wasted. ISRO has been unrelenting.

“What we’re saying is that allocate more S-band spectrum for terrestrial mobile services. The spectrum allocated for MSS is currently unutilised,” says Rajan Mathews, director general of Cellular Operators Association of India. Its use will strengthen information infrastructure and 3G services, he adds.

How S-band can improve services

G L Jogi, assistant director general with Telecom Engineering Centre, an organisation that frames specifications for telecom instruments in New Delhi, explains, “2.1 GHz is the preferred band for 3G operations worldwide and operators have rolled out 3G networks in this band. However, the band is limited.” He adds that in India the band is in short supply because there are many users and service providers. Operators thus get less spectrum and this affects the quality of service. “So, additional bands are required and 2.5 GHz forms an attractive preposition,” he says.

According to the Telecom Regulatory Authority of India (TRAI), India had 670.6 million mobile subscribers in 2010. India is expected to have around 400 million 3G connections by the end of 2015, as per Wireless Intelligence, a global database for mobile market. This will be 30 per cent of total mobile connections in the country.

Satellite phones a waste

Experts also argue that promoting satellite phones is unwise. Instead, S-band can be used for 4G.

All about S-band     S-band is part of the microwave band of the electromagnetic spectrum. Frequency of the band ranges from 2 to 4 GHz. It finds use in satellite communication, weather radars and defence. In 1980, India began using S-band for Broadcast Satellite Services for television. International Telecommunication Union later allocated it for use in mobile satellite services. The 2.5 GHz band is also being used for developing 4G technology. ISRO holds 150 MHz of the band.

C S Rao, chairperson of WIMAX Forum India, an industry-led non-profit that promotes use of 4G or WIMAX technology, says, “There’s not a single commercially proven, scalable and affordable consumer-driven satellite mobile service in the world. ISRO can’t keep holding on to the S-band in the name of low-scale MSS which has neither been proven nor found viable.” S-band should be put to use for 4G broadband services, he adds. A A Khan, additional general manager at Bharat Sanchar Nigam Limited (BSNL), agrees, “Satellite phone is very expensive to use, and very few people will be able to afford it.”

In 2009, BSNL and Mahanagar Telephone Nigam Limited (MTNL) were given 20 Mhz each of spectrum in the S-band for wireless services by the government. However, BSNL and MTNL have not been able to utilise it. The frequency—2.3 GHz—allotted to them has neither been standardised by the International Telecommunication Union for use nor are there equipment compatible with this technology. Khan adds that they have surrendered the spectrum. “The band was sold to us forcefully and we had to pay over Rs 8,000 crore for it. Now the government says the money will not be returned until the spectrum is re-auctioned.”

Sudhir Gupta, principal advisor (mobile services) in TRAI, informs that they have already recommended to the government that a part of S-band be allocated for commercial services like high-speed packet access used in 3G. “These services need a lot of spectrum and the current spectrum is not sufficient,” he adds.

ISRO did not respond to the repeated queries by Down To Earth.