Back to blog
Inmarsat IoT & M2M Iridium

May 10, 2023

Revolutionizing IoT: How Satellite Modules are Redefining Connectivity

The Internet of Things (IoT) is transforming the world as we know it, and when coupled with satellite connectivity – Satellite IoT – offers increased operational productivity, enhanced security and improved decision making, with the added benefit of unlimited, reliable connectivity.

According to IoT Analytics, by the end of 2023 an expected 16 billion IoT devices will be active. Considering the importance of reliable connectivity: How many of these devices will harness the power of satellite technology?

Graph showing ways different IoT devices are connected and how this is projected to change/grow with increasing number of devices
Source: IoT Analytics Research, State of IoT 2023
Note from authors: IoT connections do not include any computers, laptops, fixed phone, cellphones, or consumers’ tablets. Counted are active nodes/devices or gateways that concentrate the end-sensors, not every sensor/actuator. Simple one-directional communications technology not considered (e.g. RFID, NFC). Wired includes ethernet and fieldbuses (e.g. connected industrial PLCs or I/O modules); Cellular includes 2G, 3G, 4G, 5G; LPWA includes unlicensed low-power networks; WPAN includes Bluetooth, Zigbee, Z-Wave or similar, WLAN includes Wi-Fi and related protocols; WNAN includes non-short-range mesh, such as Wi-SUN; Unclassified proprietary networks include any range.

IoT connectivity continues to be dominated by Wi-Fi, Bluetooth, and cellular IoT. However, it is interesting to note that the compound annual growth rate (CAGR) for each of these technologies is expected to decrease by 2027, with cellular IoT experiencing significant decline from 200% to 87%. In contrast, satellite IoT connections are projected to exhibit strong growth, increasing from 6 million to 22 million at a CAGR of 25%.

What are satellite IoT modules?

Satellite IoT modules are small electronic devices that enable objects or devices to connect to the Internet of Things (IoT) via satellite networks. These modules are designed to provide global coverage and reliable connectivity in areas where traditional communication technologies like Wi-Fi or cellular networks may be unavailable or unreliable. Typically, satellite IoT modules are manufactured as small, compact devices that can be easily integrated into IoT devices or systems.


How do satellite IoT modules work?

In short, satellite IoT module’s works by establishing a connection with satellites in space to enable communication and data exchange between IoT devices and the central system.

IoT devices, like sensors or trackers are fitted with satellite modems (e.g., a RockBLOCK), enabling them to send data to satellites in Earth’s orbit.

In the case of a RockBLOCK, satellites within Iridium‘s constellation would then relay the data to ground stations, which act as gateways, connecting the satellite to the Network Operations Centre (NOC). From there, the data is forwarded to its intended destination, which could be a cloud platform, server, or any designated system responsible for collecting and managing IoT data.

Similarities and Differences: Satellite vs. Terrestrial IoT Modules

How do satellite and terrestrial IoT modules compare? Both offer the necessary connectivity and processing power for seamless data exchange, and come in various form factors to accommodate different deployment needs. From integrated PCBs, to ruggedized and waterproof devices with advanced features, options are plenty.

All IoT modems require an antenna, the size of which is dictated by signal strength requirements. This can differ between terrestrial and satellite devices, as satellite IoT modems need to be able to transmit data much further in order to reach satellites. However Satellite IoT devices can have surprisingly small antennas if the orbiting satellite service operates in a high frequency, like Iridium (see the patch antenna on the RockBLOCK 9603, which measures just 25 x 25 x 4mm). Other satellite network operators leveraging lower frequencies, for example Swarm, require larger, external antennas (around 20cm) in order to communicate with its satellites.

Some of the most significant differences between terrestrial and satellite IoT modules:

Connectivity Coverage

Satellite IoT modules revolutionize connectivity by leveraging satellite networks to deliver unparalleled coverage. With satellite IoT modules devices can communicate reliably from virtually anywhere on Earth, even areas with limited or no cellular coverage.

Communication Latency

Satellite IoT modules may experience higher latency due to the distance signals travel to and from satellites in space. However, with advancements in Low Earth Orbit (LEO) satellite constellations like Iridium, benefit from latency below one second. Meaning applications can achieve near real-time data exchange.

Module Cost

Satellite IoT modules may initially come with a slightly higher price tag due to their specialized hardware and software. However, as technology advances and the demand for satellite IoT applications has and continues to increase, costs have and will continues to decrease.


Satellite IoT networks prioritize robust security measures to protect data transmission and ensure privacy. Through encryption, authentication protocols, and the option of private satellite networks like TSAT, businesses can confidently safeguard data integrity and prevent unauthorized access.

VPN security


Designed for reliability, satellite networks offer resilience in the face of environmental factors, natural disasters, and infrastructure failures. With their high reliability and uptime, satellite IoT ensures consistent data transmission and device communication even in challenging and remote environments.

Consistent data transmission


Satellite IoT networks provide the scalability necessary to support a large number of connected devices. Businesses can effortlessly scale their IoT deployments without concerns about network capacity limitations or infrastructure upgrades. This scalability is particularly valuable for projects that involve numerous sensors, devices, or assets spread across expansive areas.

Two co workers mapping out project


Satellite IoT modules enable swift deployment, particularly in remote or temporary setups. By eliminating the need for new terrestrial infrastructure or relying on existing networks, businesses can establish IoT connectivity rapidly. This capability is particularly beneficial in remote or disaster-affected areas, facilitating faster response times and data collection.

Satellite connectivity installation in remote area

The Future of IoT Connectivity

According to IoT Analytics, the integration of satellite connectivity options into LPWA chipsets, led by companies like Qualcomm, has the potential to drive the adoption of hybrid IoT devices. Sony Semiconductor has already introduced ALT1350, the industry’s first cellular IoT LPWA chipset with satellite connectivity. This breakthrough expands the communication capabilities of IoT devices beyond the limitations of conventional networks, opening up new possibilities in the IoT landscape. By incorporating satellite connectivity into LPWA chipsets, further innovation and growth are expected. In the meantime, the combination of satellite and terrestrial networks continues to provide organizations with the flexibility to fully harness the potential of their IoT deployments.

Choosing the right Satellite IoT modules

When it comes to satellite IoT modules, most of them are proprietary technology tailored to a specific satellite network like Inmarsat, along with a specific airtime service such as BGAN M2M. Since each satellite network offers different coverage, reliability, and latency, and each service has its own data rates and message sizes, it is crucial for companies to carefully evaluate their connectivity needs prior to browsing hardware. Satellite connectivity can be costly, so businesses typically utilize it in areas where they face connectivity challenges or for failover and backhaul purposes. Though for any companies struggling with this, we’d recommend our article on reducing satellite IoT connectivity costs. In any case, it’s key companies assess data transmission requirements and identify the most suitable satellite airtime service for their application, before considering hardware options.

If you have any specific inquiries regarding airtime, feel free to reach out. With over 20 years of experience and strong relationships with both Iridium and Inmarsat, we are dedicated to helping you find the best solution for your project and budget, independent of any single provider.

Comparing popular Satellite IoT devices and airtime services

RockBLOCK 9603

Short Burst Data Products

Cobham 540 Explorer

BGAN M2M Equipment
Service Provider:
Connection Type:
IP-based service
IP-based service
Data Speeds:
22 Kbps up, 88 Kbps down
448 Kbps up, 464 Kbps down
Response Time:
<1 second
<1 second
<2 seconds
Global, exc. polar region
Power Efficiency:
Very high

Ideal Applications:

  • Data buoys
  • Weather balloons
  • UAVs
  • Vessel Management Systems (VMS)
  • Environmental monitoring
  • Industrial Control Systems
  • Data loggers
  • SCADA telemetry
  • Pipeline monitoring
  • Smart farming
  • Real-time surveillance
  • High volume metering
  • High volume telemetry
  • Smart grid, smart metering, reclosure control
Service Provider:

Once businesses have chosen their preferred airtime service, they should consider the interfaces and integration options provided by the satellite IoT modules. It is crucial to ensure that the modules support the necessary interfaces (e.g., UART, SPI, I2C) for seamless connectivity with IoT devices or sensors. Compatibility with standard IoT protocols (e.g., MQTT, HTTP) should also be assessed to ensure smooth integration within the existing IoT infrastructure.

Another important aspect is evaluating the size and form factor of the satellite IoT modules. Factors like space limitations, weight restrictions, and physical constraints should be taken into account. For applications that involve burying sensors or housing them within an enclosure, antenna options must be considered. Depending on the enclosure material and satellite network, an external antenna may be necessary to improve signal strength and facilitate clear line-of-sight with geostationary satellite networks.

Companies must also verify that the satellite IoT modems comply with relevant certifications and regulatory standards applicable to their target markets. Certifications like FCC, CE, and RoHS ensure adherence to quality, safety, and environmental standards. It is also important to check for any local restrictions on satellite connectivity, as some countries may require government approval.

Cost considerations associated with the satellite IoT modules should be thoroughly assessed. This includes evaluating module pricing, airtime costs, and any additional fees or licensing requirements. Taking into account the total cost of ownership over the desired lifespan of the IoT project provides a comprehensive understanding of the financial implications.

Lastly, it is necessary to evaluate power consumption, even though satellite IoT modules are designed to be power-efficient more power is required for data transmission due to the distance it needs to travel to the satellite. Depending on the deployment scenario, it may be worth considering modules that can leverage alternative power sources such as solar power, like the Iridium Edge Solar.

By carefully considering these factors, businesses can make informed decisions when selecting satellite IoT modules, ensuring optimal integration, performance, and cost-effectiveness for their specific IoT projects.

Satellite connectivity is a game-changer for IoT, enabling devices to operate in previously unreachable areas and opening up new possibilities for businesses and industries. By choosing the right satellite IoT module and airtime service, businesses can unlock the full potential of IoT and drive innovation in their respective fields.

Ready to take your IoT project to new heights?

Don't let geographical barriers hinder the growth of your IoT initiatives. Let our decades of industry experience and strong partnerships with leading satellite providers like Inmarsat and Iridium, propel your IoT projects forward.

Our team is ready to offer unparalleled guidance and support, to ensure your IoT project reaches its full potential. Take the first step today by filling in the form below.