Mangalyaan, the Mars-orbiter launched by Indian Space Research Organisation (Isro), successfully exited the sphere of influence of earth on December 1a land mark event in its year long journey to Mars. This major achievement should inspire confidence in the ability of this prestigious organisation to launch and synchronise the requisite number of low-earth-orbit satellites to connect remote and inaccessible areas to the NII backbone. An overlay of low-earth-orbit satellites will connect the remotest corner of the country and inaccessible hinterland such as Maoist-affected jungles of Chhattisgarh, Andhra Pradesh and Orissa, apart from linking island-UTs like Andaman , Nicobar and Lakshwadweep to the mainland. Such a network will also provide real-time voice, video and data communication to vessels in high seas, when they are at the mercy of the elements during cyclones.
The country has a number of indigenously built but foreign-launched geostationary satellitesINSATspositioned at an altitude of 36,000 km from the earth's surface. They essentially provide one-way TV broadcast and non-interactive, delay-tolerant communications. Starting with INSAT-1 series in 1983, these satellites, a joint venture of DoT/Indian Metrological Department/AIR and Doordarshan, have brought DTH transmission to remote areas. However, these GEOs cannot meet the requirement of real-time interactive communication, because of the about-half-second delay which is caused by 36,000 km round trip delay. This delay called 'latency' is a disability which will degrade broadband multimedia communication. GEO-based satellite links also degrade interactive voice communication due to inherent echo problem. The DoT had used INSAT satellites for long-distance calls in 1980s,but the experience was not very encouraging. Due to poor quality of service, mainly because of echo, these long-distance circuits had to be transferred to optical fibre in 1990s.
A number of broadband Satcom systems employing either medium-earth- or low-earth-orbit satellites (NGSOs) were launched by international consortia in 1990s including Motorola's Iridium and Qualcomms Globalstar. Another ambitious project called Teledesic which was hailed as the internet in the sky was abandoned because of the high capital costs in the late 1990s and lack of financial viability due to spread of terrestrial cellular mobile networks in developed countries. However, for a developing country like India which has a vast coastline of thousands of kilometres and very extensive remote and rural areas where laying optical fibre will be too expensive and time-consuming, low-earth satellites will provide the missing link for NII.
During the last two decades, the cost of satellite launch and electronic components have come down dramatically. Isro, which has built a large number of geostationary satellites and launched one (INSAT 4CR) from its own facilities at Sriharikota, should now accept the challenge to design and execute a low-earth-orbit project on the lines of the next generation Iridium scheduled by the US during 2015-17.There is also a move to revive Teledesic Version 2 under the Obama administrations National Broadband Plan to connect remote areas in the US. Isro should be able to launch the requisite number of satellites in low-earth-orbit so as to provide a latency of less than a tenth of a second which is required to give high-quality interactive voice, video and broadband internet access to the remotest areas of the country at much less cost than optical fibre which requires trenching and digging. Optical fibre is not the optimal solution to connect remote and inaccessible areas. The project should be financed from the USO Fund which has thousands of crores of rupees lying unutilised. It will complement NOFN and provide an optical fibre like link in the sky.
The author is former member, Trai and Telecom Commission