Reconfigurable Propagation Environment for Enhancing Vulnerable Road Users' Visibility to Automotive Radar

Intelligent reflecting surfaces (IRS) are a novel technology envisaged to significantly improve the performance of next generation wireless communication networks, utilizing passive reflecting elements arranged in planar arrays to reconfigure the wireless propagation environment. This study investigates the use of Intelligent Reflecting Surfaces for Vulnerable Road Users (VRU) such as pedestrians, bicycles, and wheelchair users. This can be made possible by recent advances in IRS technology and can significantly improve the radar visibility of VRUs. In this work we propose a potential use case for IRS which aims to improve the detection of traffic users by automotive radar irrespective of the object's orientation which may severely impact its observable radar cross section. Furthermore, this approach can be extended to form a network where multiple radar sensors can become aware of a VRU's presence even in cases where the users have not been directly observed by the respective sensor. Numerical results are provided to show that the proposed approach can enhance the radar detection capability of VRUs and can help to overcome the challenges due to the orientation-dependent radar cross section of targets.