A Crowd Monitoring Methodology based on the Analysis of the Electromagnetic Spectrum

In this work, a system able to monitor the crowd density detecting mobile phone communications through the analysis of the electromagnetic spectrum is proposed and experimentally assessed. The variations of the electromagnetic spectrum are collected with a low-cost spectrum analyzer, and a high gain log-periodic directive antenna (LPDA). The objective is to relate the spectral power density in a given frequency band to estimate the connections present and the number of people in a given area. In particular, a linear regression estimator, whose parameters have been calculated with the least square method modeled considering experimental data in a controlled environment, permits us to infer the number of customers detected on a given frequency band. The obtained experimental results demonstrated the efficacy of the method, which can be used not only to monitoring the number of people in a given scenario, but it also be used for commercial activities to detect the presence and pervasiveness of different mobile phone companies.