Future tech: surveying the landscape


In this feature from the latest BAPCO Journal, Revector discusses its newly developed Detector Drone, which uses controversial phone-monitoring technology to help in the search for missing people.

As long-time readers of the BAPCO Journal will know, the ‘future technology’ section, as is probably obvious from its title, tends to focus on solutions whose use isn’t yet widespread among the emergency services.

The reason for this lack of deployment is generally that the product in question is still in the process of being developed. There are some instances, however, where the technology does actually exist but legislation makes it impossible to deploy, at least in the UK.

The most obvious example of that is probably the kind of anti-drone technology which operates through the disruption of signal in order to down the target vehicle mid-flight. Another instance – and the subject of this issue’s future tech section – is a piece of surveillance equipment known as an IMSI catcher, which intercepts mobile phone traffic with the intention of tracking the physical location of a particular user.

Looking beyond the – perfectly reasonable – privacy concerns surrounding the use of such a device, however, it appears that they can be extraordinarily useful when deployed within certain contexts. One of these, at least according to security technology company Revector, is attachment to a drone during missing-persons operations.

Armed guard

Earlier this year, Revector put out a press release publicising its Detector Drone to the UK public safety sector. It described the solution as “an unmanned aerial vehicle with a mobile phone base station attached. [It] can fly over hard-to-reach areas in the aftermath of natural disasters and locate survivors through their mobile phones.

“The RDD [Revector Detector Drone] mimics a base station so mobile phones of victims connect to it, helping search and rescue teams quickly and effectively identify the location of injured or lost people.”

As informative as the release was, one thing it did not mention is that the device being used to create the aforementioned pseudo base station is in fact an IMSI catcher. While not illegal in the UK, the use of the latter is currently only permissible in very specific circumstances, for instance by the police.

Discussing the origin of the Detector Drone, and why he has invested so much time and money into its development, Revector CEO Andy Gent says: “I started the company 20 years ago, having borrowed an IMSI catcher from a friend in Washington, D.C. to detect what’s known as SIM box fraud taking place in the Caribbean. I deployed it in Jamaica and Haiti, travelling around both for hours accompanied by an armed guard.

“The IMSI catcher allows the user to scan all the cell towers in the vicinity, just like a normal phone. They can then record details about the towers themselves, signal strength and so on, essentially imitating a base station. From there, whoever’s using the device can pretend to be a mobile network operator, using a channel which they know will attract the most phones.”

He continues: “Regarding the Detector Drone, I believe that the solution holds any number of possibilities for the wider emergency services, the most obvious example of which is around search and rescue. We haven’t worked with any public safety organisations as yet, but with the right regulation we could accomplish a lot.”

Going back to the company’s origin story, SIM box fraud – for those who don’t know – is a criminal enterprise involving the installation of low-cost, pre-paid SIM cards designed to undercut international call rates. According to an article published by Inside Telecom at the end of 2019, the annual loss of revenue to the communications industry due to the practice is believed to be “substantial”.

As well as detecting criminal activity, however, Gent has also been in discussions about how the technology might be used to monitor perpetrators after they have been put away. Discussing this potential use-case, he says: “Prisons could be another potentially huge market, but again it depends on being able to change people’s mindset. I’ve been having meetings with prison governors around the world to try and accomplish that.

“Obviously, letting prisoners use mobile phones has inherent risks and many prisons don’t allow it, for instance employing jamming technology. I’ve been saying to people, don’t stop the calls, use them to monitor what’s going on across the prison.”

The reason for doing this, according to Gent, would be to establish a picture of who is using what phone, whether devices are being shared, and so on. This would then enable “social engineering”, for instance through the sending of spoof texts.

Other potential uses-cases discussed by him include monitoring phone use within airports in order to help locate known terrorists. Gent also mentions that IMSI catchers have already been deployed in parts of the world to help protect endangered wildlife from poachers.

Technical difficulties

Returning to the subject of the Detector Drone, Revector has as yet had very little contact with UK emergency services regarding the previously discussed ‘missing persons’ use-case. This is probably no surprise, particularly given the current legislation when it comes to the deployment of this kind of phone-monitoring technology. 

Working on the basis that the law could one day change to accommodate more widespread use, however, how exactly does Gent see the drone being able to help search-and-rescue organisations? Given the rigours of that kind of operational environment, meanwhile, were there any specific difficulties to be overcome in terms of the design?

“When I purchased the company a couple of years ago, one of my clients came to me asking how they might be able to get an IMSI catcher closer to certain more out-of-the-way locations,” he says. “The obvious answer to that is through the use of a drone, which not only enables the technology to be far more agile in terms of where it can go, it also makes it easier to propagate the signal. The higher up you are, the less power is required.

“In terms of the search-and-rescue piece, say someone’s stuck on top of Snowden – we can use the technology to pinpoint exactly where they are much quicker, because of the relationship between their phone and the IMSI catcher. That obviously depends on whether or not their device is on, but we already know that the solution works.”

According to Gent, one of the things that needed to be accomplished in order to make it work was – going back to the subject of power – building-in an amplifier to provide sufficient wattage. There were also other issues, for instance centring around signal interference in relation to control of the drone.

Elaborating on this, Gent says: “A big challenge was around providing the requisite power, and we’ve built some pretty intelligent switch bank filters and amplifiers over the past year. We then had to find a way to position them on the drone itself, so we specifically worked with new, lighter materials.

“At the same time, you need to look at anything which might interfere with the drone control system and GPS. After half a million pounds of extra R&D, and a meticulous process of logical fault-finding, we’ve cracked it. I can’t give away how, but we’ve cracked it.”

He continues: “We’re finding more potential uses for this technology every day. Obviously, we’re hoping the UK market will open up, but in the meantime, we’re still carrying out a lot of work in places such as Africa, where drones are being used more and more to cover large distances.”

As Gent tells it, the Revector Detector Drone could provide major benefits to UK search-and-rescue organisations when it comes to finding missing persons. Whether the legislative landscape will – or, indeed, should – change to accommodate the wider use of this, undoubtedly controversial, technology is another conversation.

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Media contact

Philip Mason
Managing Editor, Critical Communications Portfolio
Tel: +44 (0)20 3874 9216