Satellite-Based Internet

Mains: GS III – Science and technology

Why in News?

Recently, Starlink Company has decided to launch the satellite based internet services in India.

What is Internet?

Internet – Sometimes simply called the net, is a worldwide system of interconnected computer networks and electronic devices.
It is used to communicate with each other using an established set of protocols.

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Types – Internet networks can be classified into
- Ground based network
- Satellite based network

What are Ground-based networks?

Ground-based networks – They refer to terrestrial communication system that relies on infrastructure like cell towers, fiber optic cables, and other ground-based technologies.
Limitations – They are
- Economically unfeasible – Their reliance on physical infrastructure makes them economically unviable in sparsely populated regions.
- Susceptible to disasters – They are also vulnerable to disruptions from natural disasters such as floods and earthquakes.
  - For example, when Hurricane Harvey struck the Texas coast in 2017, it knocked out 70% of cell towers in affected regions.
Cannot meet demand – They often cannot meet the demand for on-the-go connectivity in remote locations or for temporary operations.

What are Satellite based networks?

Satellite based networks – These are communication systems that use satellites orbiting the Earth to transmit and receive data.
Working

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Two segments – It is composed of a space segment and a ground segment.

The space segment consists of the satellites in orbit.
Ground segment includes all equipment on Earth that communicates with them.

Life time – Service life of 5 to 20 years.

Orbits – Satellites are deployed in three main orbits:
- The Geostationary Earth Orbit (GEO)
- The Medium Earth Orbit (MEO)
- The Low Earth Orbit (LEO).

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What are the advantages of satellite based internet over ground based internet?

Reduction of user terminals – This innovation could eliminate the need for separate user terminals altogether.

User terminal is the device that is used by an end user to access the services provided by the wireless networks.

Hardware integration – As the technology becomes mainstream, specialised hardware may be integrated directly into devices like smartphones and laptops.
Wide coverage – It provides extensive and resilient coverage regardless of terrain or the presence of terrestrial infrastructure.
Resilient to disaster – It can work during extreme weather and other natural disasters.
- For example, when mobile towers fell during Hurricane Harvey in Texas coast in 2017, Viasat’s satellite internet became a lifeline for coordinating rescue operations.
Can track multiple users – It has steerable antennas that can track multiple users and ground stations simultaneously, much like moving spotlights on a stage.
Can meet demands – It can be deployed rapidly to manage sudden demand surges.
Can provide temporary connections – It also provides connectivity within moving platforms like airplanes and remote sites such as offshore oil rigs.
Operational readiness – It also enhances operational readiness in isolated conflict zones.
- For example, the Indian Army’s used it on the Siachen Glacier.
Future prospects – Companies like AST SpaceMobile and Starlink are testing direct-to-smartphone services for greater accessibility in future.

What are the applications of satellite based internet?

Communications – It provides network access to remote areas and enables the Internet of Everything (IoE).
Transportation – It will enhance navigation systems, support self-driving cars, and improve logistics.
Disaster management – In public administration and disaster management, it can power smart cities, provide early warnings, and coordinate rescue efforts.
Healthcare – The healthcare sector can benefit from telemedicine and remote patient monitoring.
Farming – Agriculture can leverage it for precision farming and crop health analysis.
Military applications – It can serve the defence forces in variety of purposes
- For example, In the Russia-Ukraine war, SpaceX’s Starlink has been pivotal for Ukrainian defence forces.
Other applications – It also has significant applications in environmental monitoring, energy exploration, tourism, and defence.

Starlink Internet Project

Starlink – It is satellite internet constellation operated by SpaceX.
It provides high-speed internet to users worldwide, including remote locations, by utilizing a network of low Earth orbit (LEO) satellites.
Mega constellation – These are networks of hundreds or thousands of satellites working in unity.
- For example, Starlink has over 7,000 satellites in orbit, with plans for up to 42,000.
Key innovation – The use of optical inter-satellite links.
These allow satellites to communicate directly with each other in space.

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This creates a true “internet in the sky,” an interconnected blanket of satellites.
Advantages – The smaller satellites are capable of on-board signal processing.
This on-board intelligence simplifies the user terminals on the ground.
Terminals become smaller, cheaper, and more accessible to individual households.
This network can route data globally with minimal reliance on ground stations, reducing latency and increasing efficiency.
This enhances data transmission efficiency, improves signal quality, and allows for greater flexibility.

What are the challenges?

Expensive – The service is still more expensive than terrestrial broadband.
- For example, the terminals cost around $500, and monthly services start at about $50.
Connectivity challenges – Maintaining continuous connectivity is a challenge.
- For example, LEO satellites move at nearly 27,000 km per hour. They stay within a user’s line of sight for only a few minutes.

To ensure uninterrupted service, the network must seamlessly “hand-off” the connection from one satellite to the next.

Potential for misuse – Borderless nature facilitates illicit use.
- For example, Security forces in India have confiscated smuggled Starlink devices from insurgent groups and drug rackets.

What lies ahead?

India could develop comprehensive strategies to integrate the technology into national resilience plans.
India could also leverage it to bridge the digital divide and foster economic development.

Quick facts

The Geostationary Earth Orbit (GEO)

Altitude – They orbit at 35,786 km above the equator.
They match the Earth’s rotation, allowing them to remain stationary relative to a point on the ground.
Advantages – The high altitude allows a single GEO satellite to cover nearly one-third of the Earth’s surface, except the Polar Regions.
- For example, Viasat’s Global Xpress (GX) system.

Viasat, is a global communications company specializing in satellite-based internet and networking systems for both commercial and government sectors.

GEO satellites are also typically large.
They act as “bent-pipes,” simply relaying signals back to Earth without processing them.
Drawback – They have high propagation latency.

Latency refers to the delay, or time it takes, for data to travel from one point to another on a network.

This makes GEO systems unsuitable for time-sensitive applications like video conferencing or real-time transactions.

The Medium Earth Orbit (MEO)

Altitude – MEO satellites operate at altitudes between 2,000 km and 35,786 km.
Advantages – They offer a compromise between GEO and LEO systems
Their latency is lower than that of GEO satellites,
Drawbacks – They still require a constellation for global coverage
- For example, O3b MEO constellation, consists of 20 satellites.
Their latency is often insufficient for many real-time applications.
The satellites remain large and costly to launch.

The Low Earth Orbit (LEO)

Altitude – They orbit at altitudes below 2,000 km
Advantages – Their proximity to Earth results in very low latency
They are also smaller, often table-sized, making them cheaper and quicker to deploy.
Drawbacks – Smaller coverage area.

Reference

The Hindu| Satellite Based Network