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ECE Prof. Yasamin Mostofi’s research featured in The UCSB Current article “Crowd Counting through Walls through WiFi”

September 24th, 2018

image from video of crowd counting research
The new methodology and experimental results were presented by Mostofi at the 2018 IEEE 15th Annual IEEE International Conference on Sensing, Communication, and Networking (SECON)

Researchers in UC Santa Barbara professor Yasamin Mostofi’s lab have given the first demonstration of crowd counting through walls using only everyday communication signals such as WiFi. The technique, which requires only a wireless transmitter and receiver outside the area of interest, could have a variety of applications, including smart energy management, retail business planning and security.

“Our proposed approach makes it possible to estimate the number of people inside a room from outside,” said Mostofi, a professor of electrical and computer engineering at UC Santa Barbara. “This approach utilizes only WiFi RSSI measurements and does not rely on people to carry a device.”

In the team’s experiments, one WiFi transmitter and one WiFi receiver are behind walls, outside a room in which a number of people are present. The room can get very crowded with as many as 20 people zigzagging each other. The transmitter sends a wireless signal whose received signal strength (RSSI) is measured by the receiver. Using only such received signal power measurements, the receiver estimates how many people are inside the room — an estimate that closely matches the actual number. It is noteworthy that the researchers do not do any prior measurements or calibration in the area of interest; their approach has only a very short calibration phase that need not be done in the same area.

This development builds on previous work in the Mostofi Lab, which has pioneered sensing with everyday radio frequency signals such as WiFi, with several publications in this area since 2009. For instance, their 2015 paper showed crowd counting without relying on people to carry a device, but with the transmitter and receiver in the same area as the people.

“However, enabling through-wall crowd counting is considerably more challenging due to the high level of attenuation by the walls,” said Mostofi. Her lab’s success in this endeavor is due to the new proposed methodology they developed.

The UCSB Current – “Crowd Counting through Walls through WiFi” (full article)

"Through-Wall Crowd Counting with WiFi, Without Relying on People to Carry a Device" (YouTube)

Mostofi Lab's research on Crowd Counting Through Walls with WiFi

More about Mostofi and her research