A mobile antenna may no longer be limited to carrying data: it can also observe what is moving around it. In Helsinki, Ericsson and Finnish public network operator Erillisverkot demonstrated that a 5G network could detect, locate and track drones in real time. The trial ran from September 16 to 18 and included a live demonstration at Vuosaari Harbor. It gives practical form to ISAC, or Integrated Sensing and Communication. Behind the acronym is a major shift: a telecom network can become a sensing network too.
Signals that can read their surroundings
The principle relies on radio-wave reflections. A base station already transmits signals to connect phones and equipment. When those signals meet an object, part of their energy returns in an altered form. By analyzing the echoes, several network points can detect movement, estimate a location and follow a trajectory. The process resembles radar, but it uses cellular infrastructure and frequencies that are already employed for communication.
During the Finnish demonstration, several network points collected sensing information at the same time. Their cooperation produced a broader picture than a single sensor could provide. This distributed dimension is crucial: small drones flying at low altitude can be difficult to track across large areas, especially when they are not connected to a network and emit no identification signal that authorities can easily use.
Why a harbor is the right laboratory
Vuosaari is a complex setting, with constant movement, metal structures, logistics activity and sensitive areas that require protection. A test in this environment is more revealing than a demonstration over a perfectly clear field. It helps teams evaluate how signals behave around obstacles and how authorities might add this new information layer to their operations.
Potential applications extend well beyond the harbor. Ericsson points to airports, borders, critical infrastructure and major public events. The need is similar in every case: obtain an alert early enough to understand what is happening and decide whether intervention is required. ISAC is not being presented as a replacement for radar, cameras or acoustic systems. It is a complementary capability that may help cover some of their blind spots.
Reusing investments already in place
The economic argument matters as much as the technical achievement. Mobile networks already cover wide territories and come with power supplies, data links, monitoring systems and physical sites. Adding sensing to that base may be faster and more scalable than installing an entirely new generation of specialized sensors everywhere.
Ericsson combines its Massive MIMO 5G radios, electronic beam steering, edge computing and signal-processing software. Artificial intelligence can then help distinguish targets, classify movement and reduce false alarms. The value does not come from one antenna. It comes from the system formed by radio equipment, computing capacity, software and connections to command centers.
Public safety opens the path
Erillisverkot provides communication services for Finnish authorities and already works with Ericsson on Virve 2.0, Finland’s next-generation public-safety network. That context explains the focus on government use cases. Organizations responsible for protecting people and sensitive sites have an immediate operational reason to experiment with emerging technology.
Early deployments may therefore involve defense, emergency services and critical-infrastructure protection. Broader commercialization is more likely in the 6G era, once standards, compatible equipment and the surrounding ecosystem mature. The Helsinki trial sits at the boundary: it uses a present-day 5G platform to explore a function expected to become native in the next generation.
6G will not simply be faster
The demonstration corrects a common assumption about network evolution. Moving to 6G will not be only about higher throughput. Standards organizations are working on architectures in which the network can communicate, compute and perceive. ETSI is already examining use cases, radio models, performance indicators, security and privacy. The 3GPP, meanwhile, has placed ISAC within its preparatory work for future specifications.
This convergence could support many other fields: traffic management, industry, robotics, object tracking, presence detection and radio-beam optimization. But moving from prototype to service will require consistent precision, common interfaces and clear governance. A network that perceives its surroundings creates a different kind of data from one that only carries messages.
The quiet privacy challenge
The security promise comes with an essential question: who may request sensing, over which area, for how long and at what level of detail? Radio reflections may reveal the presence or movement of objects even when they are not network subscribers. ETSI’s work therefore stresses the need to build access control, accountability, data protection and purpose limitation directly into the architecture.
Trust will determine whether civilian uses are accepted. Authorities will need to explain what the system actually detects, how long information is retained and how it is combined with other sensors. The technology can protect a harbor without becoming an indiscriminate surveillance tool, but radio performance alone will not guarantee that boundary.
From invisible network to sensitive territory
The Vuosaari trial marks a change of role. Until now, mobile-network quality has largely been judged by what the network carries. Tomorrow, it may also be measured by what the network understands about the space around it. For operators, that opens new services. For authorities, it provides another layer of coverage. For the public, it creates a necessary debate about acceptable uses.
Finland’s 5G network did not suddenly become an anti-drone shield. It did, however, show that communication infrastructure can provide distributed situational awareness. That is precisely why the demonstration matters: it turns an abstract 6G promise into an observable scene above the docks of a working harbor.