08 Jan 2022



Holding up US$ 9.6 billion of goods per day, the Suez canal blockage earlier this year was a poignant reminder of the immense value of raw materials, intermediate goods, and finished products that transit the globe every day. Split up between refrigerated “reefers” and dry containers, cargo containers revolutionized logistics by offering a standardized unit that could be efficiently handled and seamlessly transferred from marine vessels to train wagons to trucks. Similarly, ULDs (unit load devices) used for air freight, IBCs (intermediate bulk containers), and good old pallets (that are now becoming more connected and smarter) brought increased uniformity across logistics chains.  

With the rise of wireless connectivity and the internet of things (IoT), global cargo tracking solutions are gaining in popularity to help logistics operators, customers, and owners optimize their supply chains by keeping track of the status and whereabouts of assets on the move. Digital interoperability between the myriad cargo tracking solutions may well be the next game changer, helping to maximize the value gained from the gathered data.

Challenges in tracking cargo on land, at sea, and in the air

In a previous blog, we outlined some of the key benefits of using satellite-based positioning, sensing, wireless communication, and cloud platforms to track assets that are on the move. Deployed solutions, however, tend to face a common set of challenges, in terms of coverage, service availability, bandwidth requirements, power efficiency, security, and issues related to signal interference.

Consider a reefer, a standard container used to transport goods that need refrigeration, that is equipped with an IoT tracking and monitoring solution. At the very least, the device needs to be able to successfully detect the geographical location and status (temperature, humidity, pressure, etc...) of the container, bundle that information into a digital message, and securely transfer that message to the cloud where it becomes available to the intended users.

Zooming in on the last step – transferring the data to the cloud – reveals a critical vulnerability. The tracker might rely on cellular connectivity as the data pipe. Using a global cellular connectivity service may be an ideal solution close to shore where cellular network infrastructure is available. But as the ship enters international waters, coverage will first become unreliable and then fail altogether.

To solve this problem, container ships (and container terminals, logistics hubs, and cargo trains) often provide a wireless gateway to relay data from onboard container tracking devices to the cloud via one or several communication channels (typically cellular or satellite). With a robust data pipe to the cloud in place, the challenge thus becomes one of efficiently transferring data from the container tracker to the wireless gateway. To serve as many customers (each, potentially, with their own tracking solution) as possible, the cargo tracking solutions and the gateways need to be designed with digital interoperability in mind.

Connectivity based on open standards

Globally adopted open standards, including cellular communication, Bluetooth, and Wi-Fi, offer one way to optimally achieve interoperability. The combination of cellular and Bluetooth technology stands out as particularly promising. Because national regulations of cellular technology deployments do not apply on marine vessels operating in international waters, private cellular network deployments offer a robust, standardized, and industry-hardened communication infrastructure capable of connecting tracking devices and data loggers to the wireless gateway.

Bluetooth connectivity offers an ideal redundancy closer to shore, where regulatory requirements restrict the use of cellular connectivity. Designed for low power consumption, minimal interference with other devices, and not subject to any license restrictions on land or sea, Bluetooth natively connects to virtually all smart devices on the market. And although its range is far less than that of cellular communication, Bluetooth mesh deployments dramatically extend both coverage and reliability by letting data hop from one device to the next until it reaches its destination, the wireless gateway.

It’s an approach that in line with the one proposed by the Digital Container Shipping Association (DCSA), a non-profit, vendor-neutral organization headquartered in Amsterdam, is working with the major players across the shipping industry to promote digital interoperability across the industry through open-source standards. Focusing specifically on the communication link between container tracking devices and the wireless IoT gateway, they are pushing to establish cellular and Bluetooth technology as the internal radio interfaces of choice for on-vessel connectivity, in addition to a proprietary low-power wide-area network modulation solution.

Technological flexibility to expand location coverage beyond GPS

Just as redundant communication technologies increase the reliability and availability of device-to-gateway communication, complementary positioning technologies can increase the availability of location information. Satellite-based GPS technology delivers reliable location data to devices within line of sight of orbiting GNSS satellites, so basically anywhere outdoors. It may, however, fail if cargo containers are located near the bottom of the stack on a container ship, a logistics terminal, or in an indoor facility.

To overcome these limitations, solutions should be designed to use a diversity of approaches to determine the best available position reading given the circumstances. In the absence of GNSS coverage but when cellular networks are within range, for example indoors, cellular network fingerprinting (CellLocate) offers a coarse position estimate that far better than none at all. And when higher position accuracies are of the essence, as is often the case inside logistics hubs, warehouses, or factories, Bluetooth indoor positioning may be the solution of choice.

Despite the rapid rise of IoT-based global cargo tracking solutions, they continue to be limited by the lack of performance in edge cases – be it in terms of cloud connectivity or position availability. Solutions offering technological redundancies help overcome these limitations, on land, on sea, and in the air. And if they are based on open standards-based technologies, they can help ensure the digital interoperability needed to be able to deliver on their promise and, potentially, become the next game-changer in container tracking.

Diego Grassi

u-blox 工业市场开发部门应用营销高级经理

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