LoRa upgrade! Supports satellite communications. What new applications will it unlock?

In the second half of 2021, the British space startup SpaceLacuna used the radio telescope in Dwingeloo, the Netherlands, to bounce a LoRa message off the moon for the first time. Judging from the quality of the data captured, this was definitely an impressive experiment, as one of the messages even contained a complete LoRaWAN® frame.

Spectrogram of the received message, including the modulated call sign "PI9CAM"

Delay Doppler diagram of the received signal

It is reported that LacunaSpace uses a group of low-Earth orbit satellites to receive information from sensors integrated with Semtech's LoRa devices and ground wireless radio frequency technology. The satellites circle over the Earth's poles every 100 minutes at 500 kilometers above the ground. As the Earth rotates, the satellites cover the globe. LoRaWAN is used by satellites, which saves battery power, and messages are stored for a short time until they pass through the ground station network. The data is then relayed to applications on the ground network or can be viewed on a web-based application.

This time, the LoRa signal sent by LacunaSpace lasted for 2.44 seconds before being received by the same chip. Its transmission distance was approximately 730,360 kilometers. As of now, this may be the longest distance for LoRa message transmission.

As for satellite-to-ground communication based on LoRa technology, a milestone was achieved at the TTN (The Things Network) conference in February 2018, proving the feasibility of LoRa's application in satellite IoT. In the live demonstration at that time, the receiver captured the LoRa signal transmitted from the low-orbit satellite.

Today, using existing low-power long-range IoT technologies, such as LoRa or NB-IoT, to provide direct communications between IoT devices and orbiting satellites around the world can be considered part of the low-power wide-area network market. Before its commercial value is widely recognized, it does not prevent these technologies from becoming an interesting application direction.

Semtech's efforts: LR-FHSS fills the market gap in IoT connectivity

As early as a few years ago, Semtech began to focus on LR-FHSS, and at the end of 2021, it officially announced that the LoRa platform added support for LR-FHSS.

The so-called LR-FHSS, namely Long Range – Frequency Hopping Spread Spectrum, is also a physical layer modulation technology, just like LoRa, and its performance is mostly consistent with LoRa, such as sensitivity and bandwidth support.

LR-FHSS can theoretically support millions of terminal nodes, which significantly improves network capacity and solves the channel congestion problem that previously restricted the development of LoRaWAN. In addition, LR-FHSS also has high anti-interference ability, can alleviate data packet conflicts by improving spectrum efficiency, and has uplink frequency hopping modulation capability.

After integrating the LR-FHSS function, LoRa is more suitable for application scenarios with dense terminals and large data packets. Therefore, the LoRa satellite project integrated with the LR-FHSS function has multiple advantages:

• First, it can access ten times the terminal capacity of the LoRa network;
• Second, the transmission distance is longer, up to 600-1600km;
• Third, it has stronger anti-interference ability;

Fourth, it achieves lower costs, including management and deployment costs (no need to develop additional hardware, and it has its own satellite communication capabilities).

It is reported that Semtech's LoRaSX1261, SX1262 transceivers and LoRaEdgeTM platform and V2.1 gateway reference design all support LR-FHSS. Therefore, in real applications, the network capacity and anti-interference ability can be improved by upgrading and replacing the software of LoRa terminals and gateways respectively. For LoRaWAN networks that have already deployed V2.1 gateways, operators can enable new functions through simple gateway firmware upgrades.

Integrated LR-FHSS: LoRa continues to expand its application scope

Previously, BergInsight, an IoT market research organization, released a research report on satellite IoT. Data showed that despite the adverse impact of the COVID-19 pandemic, the number of global satellite IoT users still grew in 2020, with a total scale of 3.4 million; it is expected that the global satellite IoT users will have an annual compound growth rate of 35.8% in the next few years, reaching 15.7 million in 2025.

Currently, only 10% of the world’s regions can access satellite communication services, which provides a broad market space for the development of satellite IoT and also an opportunity for low-power satellite IoT.

LR-FHSS will also promote the development of LoRa deployment worldwide. The addition of LR-FHSS support to the LoRa platform will not only help it provide more cost-effective and ubiquitous connectivity services to remote areas, but also mark an important step towards large-scale IoT deployment in densely populated areas, which will further promote the global deployment of LoRa and further expand innovative applications:

(1) Support satellite IoT services

LR-FHSS enables satellites to connect to vast remote areas around the world, supporting positioning and data transmission needs in areas without network coverage. Relevant LoRa use cases include wildlife tracking, container positioning of ships at sea, livestock positioning on pastures, smart agricultural solutions to increase crop yields, and global distribution asset tracking for improving supply chain efficiency.

(2) Support more frequent data exchange

In the past LoRa application fields, such as logistics and asset tracking, smart buildings and parks, smart homes, smart communities, etc., the amount of LoRa modulation signals in the air will increase significantly due to the longer and more frequent signal exchanges in these application scenarios. The channel congestion problem caused by the development of LoRaWAN can also be solved by upgrading LoRa terminals and replacing gateways.

(3) Enhanced indoor depth coverage

In addition to expanding network capacity, LR-FHSS supports deeper indoor terminal nodes in the same network infrastructure, thereby improving the scalability of large-scale IoT projects. For example, LoRa is the technology of choice in the global smart meter market, and enhanced indoor coverage will further consolidate its position.

More and more players are entering the low-power satellite IoT market, and overseas LoRa satellite projects are emerging

McKinsey & Company has predicted that the output value of space-based IoT may reach US$560 billion to US$850 billion in 2025, which may be the main reason why a large number of companies are chasing this market. Currently, nearly dozens of manufacturers have proposed satellite IoT networking plans.

From the perspective of overseas markets, satellite IoT is an important area of ​​innovation in the IoT market. As part of the low-power satellite IoT, LoRa has already been widely used in overseas markets:

• In 2019, Space Lacuna and Miromico began commercial trials of the LoRa satellite IoT project, and successfully applied it to agriculture, environmental monitoring or asset tracking the following year. By using LoRaWAN, the service life of battery-powered IoT devices can be extended, saving operation and maintenance costs.

• IRNAS is working with Space Lacuna to explore new uses for LoRaWAN technology, including tracking wildlife in Antarctica and using LoRaWAN networked buoys to deploy dense sensor networks in the marine environment, supporting both moored applications and drifting.
• Swarm (acquired by Space X) has integrated Semtech’s LoRa devices into its connectivity solutions, enabling two-way communication between low-Earth orbit satellites. This opens up new Internet of Things (IoT) use cases for Swarm in areas such as logistics, agriculture, connected cars and energy.
• Inmarsat and Actility have partnered to form the Inmarsat LoRaWAN network, a platform based on the Inmarsat ELERA backbone network that provides a wealth of solutions for IoT customers, including agriculture, power, oil and gas, mining, logistics and other industries.
• …

Looking at the overseas market, there are not only many mature applications of this project, but also many companies are very enthusiastic. Omnispace, EchoStarMobile, Lunark and many other companies are trying to use the LoRaWAN network to provide IoT services with lower costs, larger capacity and wider coverage.

Final Thoughts

Although, LoRa technology can also be used to fill the gaps in rural areas and oceans that lack traditional network coverage, it is an excellent way to solve the "Internet of Everything".

However, from the perspective of the domestic market, the development of LoRa in this area is still in its infancy. Compared with overseas markets, it faces more challenges:

• On the demand side, it is not strong as maritime satellite network coverage is already very good and data can be transmitted in both directions;
• In terms of application, China is still relatively limited, mainly focusing on container projects. Given the above reasons, it is difficult for domestic satellite companies to promote the application of LR-FHSS;
• In terms of capital, since there is a lot of uncertainty in the project, the project can be large or small and the cycle is very long, so this type of project depends to a large extent on the capital investment.