PM Modi’s recent meeting with Elon Musk has suddenly triggered a discussion on this topic- resulting in a flurry of questions in the mind of the common man. So I thought about doing this FAQ. The idea of this effort is to answer some obvious questions without getting technical. So that it all resonates with the layman, who may not have any understanding of how all of this works. So without wasting any more time let's begin.
Q1. What is Satellite Internet?
Ans — Satellite internet is a service offered using satellites hanging in the sky as aggregation points, just like the ground base BTSs (Base Stations) which the telecom companies use for offering internet services.
Q2. Why do we need Satellite Internet?
Ans — We need satellite internet, as it is the only option available for offering internet services in areas where terrestrial-based mobile networks can’t reach.
Q3. Why Conventional Networks can’t reach everywhere?
Ans — Theoretically it can, but practically it is impossible. The cost of deployment will become exponentially high in sparsely populated areas, thereby making the venture totally unviable.
Q4. Why would it become unviable?
Ans — The cost of installing and maintaining Base Stations (BTSs) in areas (forests, mountains, desert, high seas, etc) — where the density of population is low, or insignificant, will be exponentially high, thereby not justifying such deployments.
Q5. Why do Satellite Services become viable in these areas?
Ans — Satellite Services are indifferent to the terrain, provided one has clear access visibility to the sky where the satellite is located. If not, like under a tree, or inside the building, satellite services can’t reach directly. On the contrary, mobile networks can, provided there is a BTS deployed nearby.
Q6. Why terrestrial network signals can reach inside buildings and not satellite networks?
Ans — Unlike mobile networks, satellite networks can’t operators at low frequencies efficiently. And to reach indoors we need the services to be carried over at low frequencies, preferably below 1 GHz. High frequencies travel in straight lines as light waves do, and cast a shadow if faced with an obstruction.
Q7. Why does satellite-based internet operate at high frequencies?
Ans — They do so as they have no option. They are caught between the rock and the hard place. Firstly, most low frequencies are occupied, and even if it was free then also it made no sense, as the Bandwidth available is very less. Low bandwidth means, low throughput, and low internet speeds. Secondly, to increase throughput satellite uses a technology called “beam steering” (like terrestrial 5G networks), and this technology only works effectively at reasonably high frequencies.
Q8. Can Satellite Services compete directly with terrestrial services?
Ans — They simply can’t. The reason is simple. Satellite Services can’t generate the same economies of scale (cheaper devices and services cost) as terrestrial-based mobile services can.
Q9. Why Satellite Services can’t be as affordable as terrestrial services?
Ans — This is due to the fact that satellite services can’t reuse spectrum as effectively as terrestrial services can. This creates a huge bottleneck in their ability to drive high capacities. Hence, as they add more users, all of them (combined) start to experience lower internet speeds.
Q10. Why satellite networks can’t reuse spectrum as effectively as their terrestrial counterparts?
Ans — The answer lies in the much higher footprint of satellite services. The footprint is similar to the coverage of the ground-based BTS. More the coverage (footprint), the lesser the number of BTSs (satellites) needed for providing services. But in the case of terrestrial networks, BTS density is deliberately increased to drive more capacities (through a process we call “geographical segmentation”). But satellite networks simply can’t, as there is always a limit to the number of satellites hanging in the sky (at a time) for serving a specific geography. For satellite networks, the only way of increasing capacity is by aggregating more spectrum. And we all know the spectrum is scarce and limited.
Q11. Can satellite networks be used to bridge the digital divide?
Ans — No. Especially in India. The key reason is the cost — both of device and service. The cheapest Starlink device is available at $550 (excluding tax), and the service cost is $100 (excluding tax).
Q12. Why can’t the cost be amortized over a large number of users using a WiFi network?
Ans — Again the problem is the BW capability per connection. That’s not all, the Achilles heel is the uplink speeds. It is very low. The key is the size of the antenna (disc) at the user end. The lower the size of the antenna (size is kept deliberately low for better maneuverability), the lesser the power that gets transmitted back to the satellite — leading to lower uplink speeds. Now if uplink speeds are low (let’s say 10 to 20 Mbps), how many users can share such a connection?
Q13. Why it makes no sense to auction spectrum for satellite services?
Ans — No single satellite player can use even a fraction of the bandwidth assigned to it exclusively. So who will use the rest? All the remaining capacity will go down the drain.
Q14. What prevents them to share spectrum among each other to overcome this limitation?
Ans — Theoretically they can, but practically it makes no regulatory, and economic sense for the satellite players to share airwaves once it is auctioned.
Q15. But why it makes no regulatory and economic sense?
Ans — It is not prudent for the regulator to hold an auction without defining the rules of sharing clearly. But, this the regulator can’t do, as spectrum sharing (especially between satellite players) is an evolving topic of discussion. Even FCC (US Rgulator) is continuously refining its sharing guidelines in alignment with the latest technical capabilities and circumstances. Therefore, once the rules are defined in the NIA (Notice Inviting Applications), these can’t be altered. Also, you can force a player to share the resources which he has acquired through the auction process (sharing is a voluntary activity in the case of terrestrial networks). This creates a lot of inefficiencies and prevents the entry of new players, even when a lot of capacity is available for many to operate simultaneously, thereby blocking the market for the selected few.
Hope you will find this useful. In case of any further queries, you can reach me on Twitter @Parag_Kar. Thanks for reading.
(Note — No conflict of interest as no one funded for writing this FAQ)
