Paving the way for economically accepted and technically pronounced smart radio environment

Recently, Reconfigurable Intelligent Surfaces (RISs) have been introduced to provide the necessary flexibility for the design of the Smart Radio Environment (SRE), which can be optimally shaped to facilitate efficient signal transmissions. In line with the concept of smart cities, SRE needs to be carefully designed with respect to the city infrastructure and utilization of resources. In this paper, we provide our vision on RIS integration into future Smart Cities by highlighting the potential technical, environmental, and economic motivations of RIS deployment in harmony with various ecosystems at a city level such as buildings facades. To this end, we are pointing out some scenarios for mitigating the conflict between RIS realization and the existing building facade's ecosystems such as advertising display and solar cells on building walls. Also, in this fashion, the proposed vision supports a win-win relationship between all stakeholders of different ecosystems. This study presents guidelines for not only enabling seamless economically accepted RIS widespread utilization but, also more technically sounding SRE by supporting enhanced RIS features and more advanced applications that cannot be attained by traditional passive RIS. Moreover, based on the current research directions, we offer promising insights for cost-effective mass production through motivating two scenarios of 'all on silicon' and 'all as metasurface' fabrication technology. With this study, we aim to encourage the meta-surface researchers, that for a broad deployment of the technical solution, economic, environmental, and other commercial requirements should be planned together, early on in the design phase.