Comparing traffic intensity estimates employing passive acoustic Radar and microwave Doppler Radar sensor

Abstract

The purpose of our applied research project is to develop an autonomous road sign with built-in radar devices of our design. In this paper, we show that it is possible to calibrate the acoustic vector sensor so that it can be used to measure traffic volume and count the vehicles involved in the traffic through the analysis of the noise emitted by them. Signals obtained from a Doppler radar are used as a reference source. Although the acoustical vector sensor (AVS), being the embodiment of acoustic radar, has a lower accuracy than Doppler radar in vehicle counting and cannot measure the vehicle speed with the same precision has certain advantages over the Doppler sensor. Namely, it does not emit any signals, it is not susceptible to electromagnetic interferences, and it allows for further analysis of audio signals, such as assessment of the road surface state (e.g., wet/dry). The acoustic radar employing AVS we developed is a new proposition of the acoustic method for road traffic monitoring. Our research also allowed a comparison of the efficiency of both methods, namely microwave and acoustic ones. In this paper, we also provide a short review of previous publications on the project.