Experiments to Assess the Implementation of A 4 GHZ Proximity Detector for Smart Crosswalk

Abstract

A microwave line-of-sight propagation scenario is tested experimentally to assess the implementation of a proximity detector for smart crosswalks. Preliminary results conducted with one human subject indicated that the particular frequency of 4 GHz could be used to monitor the presence of people, the received power decreasing sufficiently enough to make a trustful decision, able to trigger the traffic lights. Despite some expectations, further experiments conducted with more human subjects (males, females and children) demonstrated that gender and age were not relevant, the microwave link being altered in the same way. Microstrip patch array antennas were used to increase the radiative efficiency and a reference distance of 2 meters was chosen.