A French startup, Unseenlabs, detected unusual ship movements in the Strait of Hormuz using radio-frequency satellite data. According to a case study published on 28 October, the company reported a spike in vessels with no matching tracking positions during a regional conflict in March 2026. This phenomenon occurs when crew members turn off or tamper with their tracking systems, or when power is lost.
Ship Tracking Systems Have Gaps
Most large ships use an Automatic Identification System (AIS). This hardware broadcasts the vessel’s identity, position, speed, and course, helping ships avoid collisions and monitored globally. The system relies on ships keeping it active and providing accurate information.
In conflict zones, AIS becomes unreliable. Operators can turn it off, provide false data, or lose signal due to equipment failure or patchy reception. This creates blind spots, allowing ships to hide their movements, conduct ship-to-ship transfers, or operate near sensitive infrastructure without detection.
Satellites Detect Electronic Emissions
Radio-frequency (RF) satellites detect ships by picking up the radio emissions vessels naturally give off, such as from communications gear, navigation systems, and radar, rather than relying on AIS broadcasts.
According to the European Space Agency, each Unseenlabs satellite can cover an area of up to 300,000 square kilometres and locate an emitter to within about one kilometre. The technology determines position by comparing when different receivers detect the same transmission, similar to triangulation.
This creates a second, independent record of a ship’s location, which can be compared against its official AIS report. Discrepancies between the two can indicate hidden activity.
The Strait of Hormuz as a Test Case
The Strait of Hormuz, a busy and contested waterway, serves as a good test for this technology. In late February 2026, escalating conflict led to vessel attacks, transit restrictions, and altered routes. While reported shipping traffic declined, the company argued that these numbers did not fully capture the activity on the water.
With three to four RF collections daily over the area, the company compared detected emissions against AIS positions. Between March 7 and 8, the share of detections with no matching AIS position jumped from 1.8% to 12%. By March 31, unmatched emitters accounted for 9.13% of observed activity, with many clustered near the UAE coast in areas with subsea telecom cables.
The company emphasized that satellite signals alone do not indicate intent or link specific ships to infrastructure damage. Instead, the technology highlights areas for further investigation.
This approach shifts from relying on ships to self-report their positions to building an independent picture of maritime activity. For governments, insurers, and defense agencies, it enables flagging vessels that have gone dark and directing resources like radar, optical satellites, or patrols to their locations. As more shipping lanes become contested, the question shifts from ‘where does this ship say it is?’ to ‘does what we can hear match what it’s telling us?’
