On the Potential of Using Emerging Microwave Links for City Rainfall Monitoring

Sufficient and accurate weather and atmospheric observations are very important but usually require expensive equipment. This article presents the perspective of emerging communications technologies for smart cities and smart villages, as an opportunistic Integrated Sensing and Communication (ISAC) system. In recent years, wireless communication links, and in particular commercial microwave links (CMLs) traditionally employed for backhauling cellular networks, have proven to be an important source of data on atmospheric phenomena. Moreover, the increasing growth of communication networks is an effective source of high temporal-spatial rainfall information, most valuable for many applications. This article consists of two parts. First, it reviews the use of CML as an opportunistic weather sensor and provides its application for real-time rain mapping based on CMLs from China, demonstrating their characteristics. The second part is focused on the opportunities and challenges of using millimeter-wave links and line-of-sight multiple-input multiple-output (also referred to as LOS-MIMO) links for rainfall monitoring purposes in cities, where high temporal-spatial monitoring of rain is of great need.