Joint Beamforming Design for Intelligent Omni Surface Assisted Wireless Communication Systems

Abstract

Intelligent reflecting surface (IRS) has been widely considered as one of the key enabling techniques for future wireless communication networks owing to its ability of dynamically controlling the phase shift of reflected electromagnetic (EM) waves to construct a favorable propagation environment. While IRS only focuses on signal reflection, the recently emerged innovative concept of intelligent omni-surface (IOS) can provide the dual functionality of manipulating reflecting and transmitting signals. Thus, IOS is a new paradigm for achieving ubiquitous wireless communications. In this paper, we consider an IOSassisted multi-user multi-input single-output (MU-MISO) system where the IOS utilizes its reflective and transmissive properties to enhance the MU-MISO transmission. Both power minimization and sum-rate maximization problems are solved by exploiting the second-order cone programming (SOCP), Riemannian manifold, weighted minimum mean square error (WMMSE), and block coordinate descent (BCD) methods. Simulation results verify the advancements of the IOS for wireless systems and illustrate the significant performance improvement of our proposed joint transmit beamforming, reflecting and transmitting phase-shift, and IOS energy division design algorithms. Compared with conventional IRS, IOS can significantly extend the communication coverage, enhance the strength of received signals, and improve the quality of communication links.

Joint Transceiver Beamforming and Reflecting Design for Active RIS-Aided ISAC Systems

“…According to the definition of Y in (25), it can be inferred that Y is a positive semi-definite Hermitian matrix and C 1 is a non-convex constraint, which makes P 2 non-convex. In order to deal with this formidable undertaking, we exploit the firstorder Taylor expansion [40] to obtain an suitable surrogate function for wH Y w and transform C 1 into a linear constraint, which is given by…”

“…Accordingly, there has been a growing interest in a burgeoning concept known as intelligent omni-surface (IOS) or simultaneously transmitting and reflecting (STAR)-RIS [? ], [23]- [25] recently, which aims to achieve complete coverage of the entire space. A STAR-RIS enabled ISAC framework was first brought up in [26] to minimize the Cramer-Rao bound (CRB) of the sensing target under the minimum communication requirement, and verified the efficacy of employing STAR-RIS to concurrently facilitate accurate sensing and highquality communication on both sides.…”

A Survey on STAR-RIS: Use Cases, Recent Advances, and Future Research Challenges

“…Consequently, IOS represents a novel paradigm for establishing ubiquitous wireless technology. Cai et al [70] presented IOS with a MU-MISO scheme that makes use of IOS's reflecting and transmissive properties to enhance MU-MISO broadcast. Using the Riemannian manifold, weighted minimum mean square error (WMMSE), second-order cone programming (SOCP), and block coordinate descent (BCD) algorithms, both the power minimization and sum-rate maximization problems were solved.…”

“…In addition, several IOS based system issues, such as hardware flaws, quick channel estimation, realistic transmission protocols, the creation of more complex procedures, learning-based methods, etc., should be examined in future research. Unlike the MU-MISO based work in [70], Niu et al [71] investigated MIMO using STAR-RIS support. Utilizing the ES scheme predominantly, the authors seek to optimize the weighted sum rate of the system under consideration.…”

An artificial intelligence approach for energy‐aware intrusion detection and secure routing in internet of things‐enabled wireless sensor networks

“…In recent decades, Wireless communication has become the more predominant technology for signal transmission that does not require the use of wired media. 1 They send signals using air as a medium of transmission. Wi-Fi adapters installed in a business or on a college campus are one of the best examples.…”