Reconfigurable intelligent surfaces (RISs), also known as reflecting (IRSs), or large (LISs), <xref ref-type="fn" rid="fn1" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">¹</xref> have received significant attention for their potential to enhance the capacity and coverage of wireless networks by smartly reconfiguring propagation environment. Therefore, RISs are considered a promising technology sixth-generation (6G) communication...

A novel simultaneous transmitting and reflecting (STAR) system design relying on reconfigurable intelligent surfaces (RISs) is conceived. First, an existing prototype reviewed, the potential benefits of STAR-RISs are discussed. Then key differences between conventional reflecting-only RISs identified from perspectives hardware design, physical principles, communication design. Furthermore, basic signal model introduced, three practical protocols proposed for their operation, namely energy...

In this letter, simultaneous transmitting and reflecting reconfigurable intelligent surfaces (STAR-RISs) are studied. Compared with the conventional reflecting-only RISs, coverage of STAR-RISs is extended to 360 degrees via transmission reflection. A general hardware model for presented. Then, channel models proposed near-field far-field scenarios, based on which diversity gain analyzed compared that RISs. Numerical simulations provided verify analytical results demonstrate full order can be...

Reconfigurable intelligent surface (RIS)-aided near-field communications are investigated. First, the necessity of investigating RIS-aided and advantages brought about by unique spherical wave-based propagation discussed. Then, family patch array-based RISs metasurface-based is introduced along with respective channel models. A pair fundamental performance limits communications, namely, their power scaling law effective degrees freedom (EDOF), analyzed for both RISs, which reveals potential...

A correlated transmission and reflection (T&R) phase-shift model is proposed for passive lossless simultaneously transmitting reflecting reconfigurable intelligent surfaces (STAR-RISs). STAR-RIS-aided two-user downlink communication system investigated both orthogonal multiple access (OMA) non-orthogonal (NOMA). To evaluate the impact of T&R on performance, three configuration strategies are developed, namely primary-secondary (PS-PSC), diversity preserving (DP-PSC), T/R-group (TR-PSC)...

Given the rapid development of advanced electromagnetic (EM) manipulation technologies, researchers have turned their attention to investigation smart surfaces for enhancing radio coverage. Simultaneously transmitting and reflecting (STAR) intelligent omni-surfaces (IOSs) constitute one most promising categories. Although previous research contributions demonstrated benefits simultaneously (STAR-IOSs) in terms wireless communication performance gains, several important issues remain...

A hardware model for active simultaneously transmitting and reflecting reconfigurable intelligent surfaces (STAR-RISs) is proposed consisting of reflection-type amplifiers. The amplitude gains the STAR element are derived both coupled independent phase-shift scenarios. Based on model, an STAR-RIS-aided two-user downlink communication system investigated. Closed-form expressions obtained outage probabilities To obtain further insights, scaling laws diversity orders users. Analytical results...

In the past decade, Artificial Intelligent & Internet of Things (AIoT) has become disruptive force reshaping our lives and works. Billions AIoT devices around world are now connected to Internet. This widespread deployment presents huge challenges for centralized AI training architecture (e.g., security issues, privacy issues). Recently, with advance federated learning (FL) technology, integration FL is considered as a promising solution. enables distributed collaboratively train shared...

A simultaneously transmitting and reflecting surface (STARS) aided terahertz (THz) communication system is proposed. novel power consumption model proposed that depends on the type resolution of STARS elements. The spectral efficiency (SE) energy (EE) are maximized in both narrowband wideband THz systems by jointly optimizing hybrid beamforming at base station (BS) passive STARS. 1) For systems, independent phase-shift STARSs investigated first. resulting complex joint optimization problem...

The reconfigurable intelligent surface (RIS) is a promising technology to provide smart radio environment. In contrast the well-studied patch-array-based RISs, this work focuses on metasurface-based RISs and simultaneously transmitting reflecting (STAR)-RISs where elements have millimeter or even molecular sizes. For these meticulous metasurface structures, near-field effects are dominant continuous electric current distribution should be adopted for capturing their electromagnetic response...

ABSTRACT The moving morphable component (MMC) topology optimization method has garnered increasing attention recently due to its ability provide explicit geometric parameters of optimized structures and seamless integration with CAD systems. However, the classical MMC may encounter instability during iterative process excessively free movement components defects caused by incomplete fusion components. This article proposes a novel joint‐driven (JMMC) address these issues. core idea involves...

Energy ScienceAccepted Papers No AccessResearch progress and development trend of high-density completion fluids for deep water oil gas drillingJinsheng Sun, Wenbiao Li, Bo Liao, Kaihe Lv, Jintang Wang, Qi Yiyao Jiaqi Xu, Zhijun He, Yang BaiJinsheng Lihttps://orcid.org/0009-0005-0614-5731 Search more papers by this author , Liao Lv Wanghttps://orcid.org/0009-0008-3256-5897 Wang Li Xu He Bai https://doi.org/10.1142/S2972379525300019Cited by:0 (Source: Crossref) Next...

Performance analysis is carried out in a near-field multiple-input multiple-output (MIMO) system for both discrete and continuous aperture antennas. The effective degrees of freedom (EDoF) first derived. It shown that MIMO systems have higher EDoF than free-space far-field ones. Additionally, the further depends on communication distance. Based derived EDoF, closed-form expressions channel capacity with fixed distance are obtained. As advance, randomly deployed receivers, ergodic Simulation...

The reconfigurable intelligent surface (RIS) is one of the promising technologies contributing to next generation smart radio environment. A novel physics-based RIS channel model proposed. In model, signal reflected through scatters and elements are jointly studied as multipath components overall received envelope. This strategy simplifies mathematical structure gain able compactly derive distribution channel. For case continuous phase shifts, depends on number observing direction receiver....

A hardware model and a signal are proposed for dual-sided simultaneously transmitting reflecting reconfigurable intelligent surfaces (STAR-RISs), where the incident on both sides of surface. Based model, models STAR-RISs developed. For elements with scalar surface impedance, it is proved that their transmission reflection coefficients identical. obtained symmetrical STAR STAR-RIS-aided two-user uplink communication system investigated non-orthogonal multiple access (NOMA) orthogonal (OMA)...

Full duplex techniques can potentially double the channel capacity and achieve lower delays by empowering two radios to simultaneously transmit in thesame frequency band.However, full is only available between adjacent nodes within communication range. In this paper, we present BiPass break limitation.With help of capable relays, weenable simultaneous bidirectional in-band cut-through transmissions far apart nodes, so they do communications as if were each other's transmission range.To...

Sketch is a compact data structure for network measurements. To achieve fast speed, it needs to be held in the on-chip memory (SRAM), which very small. enable sketch fit into memory, product of counter size and number counters must below certain limit. If we use small counters, e.g., 8 bits, some will overflow. large 16 bits per counter, total small, each shared by more flows, leading poor accuracy. address this issue, propose generic technique: self-adaptive (SA Counter). When value works...