Using a wireless signal to detect crowd density

How do you measure crowds without violating privacy? How about using a wireless band?
Written by Greg Nichols, Contributing Writer

There's now a growing cottage industry of tools designed to measure crowd density and count occupants in given spaces. In other words, as I've written, a new surveillance reality is setting in as we resume lockdowns and try our best to rekindle dreams of dining in. Thanks, coronavirus.

Fortunately, most of the development seems to prioritize privacy. Companies like Outsight and Athena have leveraged compact sensing technologies with cutting edge AI to build sensing and detection platforms for things like crowd and biostat monitoring that don't rely on captured video or identifying data. 

Now the University of Antwerp and imec, an R&D innovation hub, have spun off CrowdScan, a system that measures the density of a crowd in real-time using a wireless sensor network. 

The system does away with the camera altogether and doesn't rely on mobile phone data or other information that could raise privacy concerns. Instead, the system transmits 868 MHz radio waves and measures signal attenuation. It compares the results to a benchmark of attenuation in the empty environment to calculate crowd size.

"There will be no mass events this summer, but the importance of accurate information on crowd densities has only increased since the coronavirus crisis," says Ben Bellekens, CEO of CrowdScan. "By providing police and emergency services with accurate information on crowd densities, they can make fast, objective decisions. This can help cities guarantee social distancing at places where population density is high, like city streets, public events, or parks. CrowdScan also aims to make an online 'crowd barometer,' to show population density at specific places."

For privacy advocates, the use of a non-recording technology to monitor crowd size will be welcome. 

The technology was in the works long before the coronavirus pandemic. It was first validated at large-scale events, like Tomorrowland, back when large-scale events were a thing. More recently the business model has shifted away from events, for obvious reasons, and toward services that help local governments and cities. One recent pilot measured the size of groups congregating in public spaces near the MAS museum in Antwerp.

"In Antwerp's innovation ecosystem for metropolitanism and smart city, our university is focusing more than ever on value creation from research," says Silvia Lenaerts, Vice-Rector Valorization & Development of the University of Antwerp. "To do this, we collaborate with the city government, local businesses, and citizens." 

The spinoff highlights the value of innovation hubs focused on technology transfer and development. 

"Open innovation hubs such as The Beacon facilitate this process by bringing people together and actively setting up projects that effectively benefit partners. That's how CrowdScan grew into a startup that, due to the coronavirus crisis, became more relevant than ever. This spin-off is a textbook example of how scientific research from the Faculty of Applied Engineering Sciences can actually generate an impact on society."

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