Prof. Yingying Chen's team at DAISY Lab received the best paper award at the ACM International Conference on Mobile Computing and Networking (MobiCom) 2011. The project "Detecting Driver Phone Use Leveraging Car Speakers" is led by Prof. Yingying Chen of Stevens Institute of Technology and Profs. Marco Gruteser and Richard Martin of WINLAB at Rutgers University.

The paper "Detecting Driver Phone Use Leveraging Car Speakers", authored by Jie Yang, Simon Sidhom, Gayathri Chandrasekharan, Tam Vu, Nicolae Cecan, Hongbo Liu, Yingying Chen, Marco Gruteser, and Richard Martin addresses the problem of distinguishing between a driver and passenger using a mobile phone, which is a key milestone for enabling numerous driver safety and phone interface enhancements. The project developed a detection system that leverages the existing car stereo infrastructure, in particular, the car speakers and hands-free Bluetooth system.

The detection system uses an acoustic ranging approach wherein the phone sends a series of customized high frequency beeps via the car stereo. The beeps are spaced in time across the left, right, and if available, front and rear speakers. After sampling the beeps, it times their arrival via a sequential change-point detection scheme, and then uses a differential ranging approach to estimate the phone's distance from the car's center. From these differences a passenger or driver classification can be made. Experiments with two different phones and two different cars showed that the customized beeps were imperceptible to most users, robust to background noise, and achieved a classification accuracy of 90-95 percent depending on the degree of calibration.