Related references
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Article
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Kunzan Liu et al.
Summary: To overcome the power consumption issue of the existing fully-connected architecture of active RIS, a sub-connected architecture is proposed. It reduces power consumption by sharing a power amplifier among multiple elements while sacrificing degrees of freedom for beamforming design. Analysis shows that the performance loss introduced by the sub-connected architecture is minimal, achieving higher energy efficiency.
IEEE COMMUNICATIONS LETTERS
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Nhan Thanh Nguyen et al.
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Trinh Van Chien et al.
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IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS
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Zhe Wang et al.
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IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS
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Arman Shojaeifard et al.
Summary: This article provides an overview of conventional reflection-based RIS technology and its synergy with CF mMIMO. It also discusses surface-wave-assisted RIS that utilizes metasurface technologies. Additionally, it introduces fluid antenna technology and its potential combination with RIS.
PROCEEDINGS OF THE IEEE
(2022)
Proceedings Paper
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Nhan T. Nguyen et al.
Summary: This paper studies a multi-user MISO communications system assisted by a hybrid RIS. Unlike conventional RISs, the hybrid RIS is equipped with active elements that can reflect and amplify signals to improve system performance. A fairness-oriented design is achieved through jointly optimizing transmit beamforming vectors and RIS coefficients. The challenging nonconvex problem is efficiently solved using a low-complexity iterative algorithm. Numerical results show that the hybrid RIS with a power budget of -1 dBm and 4 active elements outperforms a fully passive RIS by achieving an 80% improvement compared to a 27% improvement.
2022 IEEE 23RD INTERNATIONAL WORKSHOP ON SIGNAL PROCESSING ADVANCES IN WIRELESS COMMUNICATION (SPAWC)
(2022)
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IEEE TRANSACTIONS ON COMMUNICATIONS
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IEEE TRANSACTIONS ON COMMUNICATIONS
(2021)
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Majid H. Khoshafa et al.
Summary: The use of active elements in RIS significantly reduces the size of the structure to achieve desired performance levels. A practical design for active RIS is proposed to overcome the double-fading problem in wireless communications systems.
IEEE COMMUNICATIONS LETTERS
(2021)
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Chen Hu et al.
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IEEE TRANSACTIONS ON COMMUNICATIONS
(2021)
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Jiakang Zheng et al.
Summary: This paper investigates the impact of channel aging on the performance of CF massive MIMO systems and draws several conclusions: in the uplink, the CF system achieves higher SE than the SC system; in the downlink, coherent transmission has higher SE than non-coherent transmission; statistical channel cooperation power control can mitigate inter-user interference.
IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS
(2021)
Article
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Wankai Tang et al.
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IEEE WIRELESS COMMUNICATIONS
(2021)
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Shaocheng Huang et al.
Summary: In this study, a decentralized cooperative beamforming framework for cell-free networks aided by intelligent reflecting surfaces (IRS) is proposed to increase system sum-rate efficiently. The proposed method outperforms existing decentralized methods and asymptotically approaches the performance of centralized optimization as the number of iterations increases.
IEEE WIRELESS COMMUNICATIONS LETTERS
(2021)
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Peng Xu et al.
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IEEE WIRELESS COMMUNICATIONS LETTERS
(2021)
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Zhe Wang et al.
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IEEE COMMUNICATIONS LETTERS
(2021)
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Qingqing Wu et al.
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IEEE TRANSACTIONS ON COMMUNICATIONS
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Changsheng You et al.
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IEEE WIRELESS COMMUNICATIONS LETTERS
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Si-Nian Jin et al.
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Jiguang He et al.
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IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS
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Summary: This paper introduces a novel concept of hybrid relay-reflecting intelligent surface (HR-RIS), which can significantly improve spectral efficiency (SE) through optimized design, even with a limited power budget. The design and deployment of HR-RIS are analytically derived and numerically justified for enhanced performance.
2021 IEEE INTERNATIONAL CONFERENCE ON COMMUNICATIONS WORKSHOPS (ICC WORKSHOPS)
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Jiguang He et al.
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