Digital cultivation and planting system based on Internet of Things

Abstract

This paper presents a new integrated sensing and communication (ISAC) framework, leveraging the recent advancements of reconfigurable distributed antenna and reflecting surface (RDARS). RDARS is a programmable surface structure comprising numerous elements, each of which can be flexibly configured to operate either in a reflection mode, resembling a passive reconfigurable intelligent surface (RIS), or in a connected mode, functioning as a remote transmit or receive antenna. Our RDARS-aided ISAC framework effectively mitigates the adverse impact of multiplicative fading when compared to the passive RIS-aided ISAC, and reduces cost and energy consumption when compared to the active RIS-aided ISAC. Within our RDARSaided ISAC framework, we consider a radar output signal-tonoise ratio (SNR) maximization problem under communication constraints to jointly optimize the active transmit beamforming matrix of the base station (BS), the reflection and mode selection matrices of RDARS, and the receive filter. To tackle the inherent non-convexity and the binary integer optimization introduced by the mode selection in this optimization challenge, we propose an efficient iterative algorithm with proved convergence based on majorization minimization (MM) and penalty-based methods. Numerical and simulation results demonstrate the superior performance of our new framework, and clearly verify substantial distribution, reflection as well as selection gains obtained by properly configuring the RDARS.Index Terms-Reconfigurable distributed antennas and reflecting surfaces (RDARS), integrated sensing and communication (ISAC), signal-to-noise ratio (SNR) maximization. I. INTRODUCTION A. BackgroundBy 2025, it is expected that 75.4 billion devices will be interconnected within the vast landscape of the Internet of Things (IoT) [1]. This rapid expansion lays the foundation for an interconnected future world, but it also places a heavy burden on wireless communication networks, intensifying the issue of spectrum congestion. On the other hand, emerging applications introduced by IoT, such as smart homes, robot navigation, and autonomous vehicles, demand not only highquality wireless connectivity, but also an elevated capacity to perceive and comprehend the environment [2]. These pose new challenges and requirements for next-generation wireless communication systems.In response to the above challenges, integrated sensing and communication (ISAC) emerges as a promising technology [3]- [6]. ISAC opens the door for communication to tap into