Low Earth Orbit (LEO) IoT satellites unlock the potential of IoT for remote areas, dealing with the lack of proper connectivity in these scenarios (terrestrial connectivity serves only 10-15% of the Earth’s surface).
These satellites give rise to Low Power Global Area Networks (LPGAN) enabling faster growth of applications in verticals such as agriculture, oil and gas, global mobility-transport and logistics, maritime and environmental.
Although LEO IoT satellites are not a panacea for all the IoT challenges (see my post on massive IoT), they open up a new world of opportunities, complementing the existing terrestrial connectivity offered by low power terrestrial networks (LPWAN).
According to a research report from Berg Insight (Oct 2021), the global satellite IoT subscriber base grew to surpass 3.4 million in 2020. They forecast that the number of satellite IoT subscribers will increase at a compound annual growth rate (CAGR) of 35.8 per cent, to reach 15.7 million units in 2025. This seems an excellent business opportunity, beyond the exact figures that normally are hardly met.
But what is LEO? And who are the IoT satellite operators?
Since the launch of the first satellite in 1957, the satellite technology has been historically dominated by GEO satellites, i.e. those on a geosynchronous equatorial orbit (at exactly 35,786 kilometres above Earth’s surface) remaining stationary over the same spot (hence the name geostationary). They appear fixed to an observer, as they move at the same angular velocity as the Earth. This is the type of satellite that you may have used, as they provide coverage to a specific area for many applications, including broadcasting (television and radio) and weather forecasting. These satellites should not be confused with LEO satellites.
LEO (Low Earth Orbit) satellites are in an earth-centred orbit below an altitude of 2,000 km from Earth (typically around 500 or 600 km) -by comparison, most commercial aeroplanes do not fly at altitudes higher than approximately 14 km-.
Low Earth orbit satellites move fast, around 20,000 km/h!, and they make 12-16 Earth turns per day (with an orbit period of 90-120 minutes). That means that for an observer on the Earth, the maximum time she sees a LEO satellite above the horizon is up to 20 minutes. This time is used by an IoT ground device to send the data messages up to the satellite (directly or through a gateway). Then when the satellite pass over a ground station sends the data to the station, that delivers it to the final destination (normally a platform that sends an alarm or a customer dashboard).
Compared with the traditional GEO communications, LEO satellites have the advantages of low propagation delay, small propagation loss and global coverage. Noting that to provide global coverage, they need to be part of a constellation with enough satellites. Besides, LEO IoT technology enables smaller and lower cost user terminals.
Their major limitation is that they have a shorter lifespan (approximately 5 years). LEO constellations require the constant replacement of satellites, as they move in a much harder environment (radiation and atmospheric) at such low altitudes.
Not every type of LEO satellite meets the IoT requirements regarding low-power and low-cost requirements. LEO satellites need to be optimised (e.g. reduce power consumption) so they usually are: i) small satellites, smallsat, or ii) being a multi-purpose LEO constellation (e.g. Inmarsat ELERA) to use optimised techniques and apply an efficient business model.
Orbcomm, Inmarsat, Iridium and Globalstar are the largest satellite IoT operators. Besides the incumbent satellite operators, several initiatives under the New Space umbrella have appeared: Hiber (Netherlands), AstroCast (Switzerland), Fleet (Australia), Kepler (Canada), Kineis (France), Lacuna (UK), Myriota (Australia), Swarm (USA), XingYun (China). Many of them are based on low-earth orbit smallsat concept and have developed a lot of innovation to make IoT satellites using LEO make sense from both a technical and business view. (Note that LEO satellites players providing broadband internet connectivity, like SpaceX, Oneweb and Blue Origin are out of this article).
Some companies provide satellites tracking in Low Earth Orbit, as LeoLabs Inc < click to see what is happening in the LEO space.
LEO IoT satellites enable faster growth of applications in several verticals
IoT devices sometimes need to be deployed in remote areas (ocean, desert, forest..) or placed in special topographies (mountains..) where terrestrial connectivity either has no access or the business case just doesn’t work. Satellite can cover these scenarios.
LPGAN networks with LEO satellites enable faster growth of applications in verticals such as agriculture, oil and gas, global mobility-transport and logistics, maritime and environmental.
Let me remind you that the opportunity is focused on finding suitable use cases in remote locations demanding i) low-data rates, i.e. limited number and length of data transmissions (a few messages a day from Bytes to kBytes), ii) low-power (hence devices with long battery life) and iii) low-cost solutions. The key challenge (as with any IoT use case) is to make the business case works, so the connectivity price is claimed to be like in LPWA terrestrial networks.
We can find a good example of LEO IoT application in the oil and gas sector, providing connectivity to remote oil fields (offshore and onshore). Hiber, an end-to-end IoT solution startup, has an agreement with Shell to provide well integrity monitoring globally, using LEO satellites. The benefits are clear: Hiber solution allows Shell to measure real-time well temperatures and pressure on remote and offshore wells. Besides, they monitor integrity issues more effectively, improving the productivity and security of those wells. And the business case works in this case (this is always the main issue regarding IoT adoption): Shell uses Hiber solution to reduce the amount of travel to and from wells in remote locations (90% reduction) and saving tens of thousands of euros per well on trips and interventions. Simple, clear and productive.
Adopting a Hybrid model to succeed
Let me give you some hints for LEO IoT satellites to work as one of the main enablers for the IoT market.
Hybrid connectivity approach
- LEO satellites are a missing piece for IoT growth. But they would be more efficient as part of a Hybrid model, combining LEO IoT satellites with existing terrestrial solutions (LPWA). The connectivity and device specifics have to be set up according to the context of each IoT use case/business
- There are two major ways to get data messages from an IoT device (sensor) through a satellite. Which approach to choose?
- Via a terrestrial gateway: connecting the device to a terrestrial gateway that uses the satellites as a backhaul. The major benefit of this approach is that existing devices remain unchanged, leveraging the existing LPWA ecosystem (e.g. LoRa, Sigfox) to connect several devices to the gateway. Use this approach with existing devices in a few kilometres range (besides, the devices need to meet the price requirements of the business case). For example, in the oil and gas example I mentioned above, they placed several LoRa devices on the wells around a 10km range from the terrestrial gateway
- Direct connection: the device transmits directly to the satellite (the gateway in this case is on the satellite). This is a more tricky approach to leverage existing devices because they would need different antenna and firmware (and the protocol if they use a different radio). This makes more sense for new devices or when there are only a few IoT devices (or just one) within a location range (several kilometres)
- Another choice to make is which protocol to use in the satellite link (from earth to satellite). Here you have two main alternatives again:
- Using an existing LPWA protocol as LoRa, Sigfox, NB-IoT or even 5G. I would leave this option just for the medium term because there are still some problems to solve, both technical (mainly the Doppler effect, the link budget and interferences) and of course making that at a reasonable cost. There is a great presentation by Lacuna explaining these issues. Several initiatives are leveraging terrestrial IoT connectivity technologies in the satellite link, including OQ Technology, AST SpaceMobile, Omnispace, Sateliot and Galaxy Space (3GPP 4G/5G); EchoStar Mobile and Lacuna Space (LoRaWAN); and Eutelsat (Sigfox)
- Adopting a proprietary satellite protocol. This is the option I would choose for the short term. Although it requires re-engineering existing LPWA devices to use the modem, you have the alternatives to use either a gateway or a new device
Business case
- Regarding costs, there are several areas to consider, i) the connectivity cost ii) the device cost, including the antenna, the radio and the gateway iii) for LEO operators, the cost of satellite, the cost of launch and ground stations. Although makes sense to think that connectivity costs would be higher than the terrestrial option in the mid-term, nowadays exists some cases low enough (10-20 euros per month) to compete. That is not the case for hardware costs that despite having fallen notably in the last few years, a lot of innovation has to be applied yet to make the business case works, particularly for the gateway (to reach a few hundred euros cost from the existing few thousand euros range)
- On the revenue side, reaching a high customer base at a global scale is critical to succeeding in this business. Low-cost solutions require a volume in the range of millions of subscribers
- One of the major trends in IoT business is that a lot of existing players, for example device vendors or operators, transitioned into end-to-end IoT solution providers, delivering services on their own. This makes little sense to me, as I believe IoT needs specialists covering each critical piece of the IoT business. Regarding IoT satellites operators, we have seen already a few ones made that move, both in incumbent operators and the new LEO smallsats. I think that to succeed they have to develop an effective product strategy going beyond what they did in the past (e.g. LEO IoT operators, satellite device provider…)
Next coming years will be critical to find out if LEO IoT networks can revolutionise IoT, becoming an essential piece for a successful business.
