Skip to main content

'ISRO's nanosatellites can become a global system for navigation' (downtoearth)

In 2016, the Indian Space Research Organisation (ISRO) created an independent Indian Regional Navigation Satellite System (IRNSS) for national applications. This system, NavIC, has seven satellites which provide positioning, navigation and timing service over India and its neighbourhood. However, to expand the coverage to entire earth, efforts are needed. Vibha Varshney talks to Vinod Kumar, deputy project director, AOCS (Attitude and Orbit Control System), control dynamics and simulation group of the ISRO on the sidelines of 104th Indian Science Congress on what can be done to make NavIC a global navigation system.

Can you make NavIC a global system?

The seven satellites that are part of the system are placed above 35,786 km from the Earth’s surface called geostationary earth orbit. So far, the NavIC signal is available only in India and in its neighbourhood covering 1,500 km. It is proposed that multiple nanosatellites can be launched at low earth orbit which would work in collaboration with the existing NavIC satellites. These nanosatellites will be in touch with the stationary satellites only for some part of the day to recalibrate their equipment like quartz clock. A discrepancy of 100 nanoseconds in clock would affect the positioning by 30 metres. These satellites will use NavIC signal as measurement and we can then use mathematical models during NavIC non-visibility periods.

We are still in the study phase. These nanosatellites at low earth orbit along with existing NavIC in GEO/GSO can become a global system for navigation. We can think of putting around 50 satellites that can be networked together.

Why should a common person shift from GPS to your system?

A person who has a NavIC receiver can use this service across the world. This receiver could even be part of mobile phones if industry shows interest.  We have seen that during critical times GPS and navigation service providers can deny the service to other countries. At present only four countries have such navigation satellites.

The Indian system would help a common person, too. While the GPS satellites are dynamically changing their position with respect to an observer on earth, NavIc satellites are stationary and are more accurate in Indian region.

Moreover, satellites that provide positioning services carry costly and heavy atomic clocks but these high fidelity mathematical models can offer same information provided by the clocks and thus, avoid this cost.



Comments

Popular posts from this blog

SC asks Centre to strike a balance on Rohingya issue (.hindu)

Supreme Court orally indicates that the government should not deport Rohingya “now” as the Centre prevails over it to not record any such views in its formal order, citing “international ramifications”.

The Supreme Court on Friday came close to ordering the government not to deport the Rohingya.

It finally settled on merely observing that a balance should be struck between humanitarian concern for the community and the country's national security and economic interests.

The court was hearing a bunch of petitions, one filed by persons within the Rohingya community, against a proposed move to deport over 40,000 Rohingya refugees. A three-judge Bench, led by Chief Justice of India Dipak Misra, began by orally indicating that the government should not deport Rohingya “now”, but the government prevailed on the court to not pass any formal order, citing “international ramifications”. With this, the status quo continues even though the court gave the community liberty to approach it in …

Khar’s experimentation with Himalayan nettle brings recognition (downtoearth)

Nature never fails to surprise us. In many parts of the world, natural resources are the only source of livelihood opportunities available to people. They can be in the form of wild shrubs like Daphne papyracea and Daphne bholua (paper plant) that are used to make paper or Gossypium spp (cotton) that forms the backbone of the textile industry.

Nothing can compete with the dynamism of biological resources. Recently, Girardinia diversifolia (Himalayan nettle), a fibre-yielding plant, has become an important livelihood option for people living in the remote mountainous villages of the Hindu Kush Himalaya.

There is a community in Khar, a hamlet in Darchula district in far-western Nepal, which produces fabrics from Himalayan nettle. The fabric and the things made from it are sold in local as well as national and international markets as high-end products.

A Himalayan nettle value chain development initiative implemented by the Kailash Sacred Landscape Conservation and Development Initiati…

The Chipko movement as it stands today

The idea behind the Chipko movement originated in early 1970s from Mandal, a village in Chamoli district of Uttarakhand. Forty-three years later, Down To Earth travelled to Chamoli and Tehri Garhwal and spoke to the participants of this movement about its relevance today