S. Panichpapiboon and P. Leakkaw, “Traffic Density Estimation: A Mobile Sensing Approach,” ​ IEEE Communications Magazine, vol. 55, no. 12, pp. 126-131, Dec. 2017.

Traffic density is one of the fundamental traffic variables used in modeling road traffic dynamics. It measures how packed the vehicles are on the observed road space. Typically, traffic density is estimated indirectly from the data collected by fixed sensors such as inductive loop detectors. However, using fixed sensors has limitations in terms of cost and coverage. It is more effective and less expensive to use vehicles as mobile sensors. With the wide adoption of smartphones, mobile traffic sensing has become more realizable. In this article, we explore the possibility of using only the built-in sensors of off-the-shelf smartphones for traffic density estimation.