Resource Allocation for IRS-Assisted Full-Duplex Cognitive Radio Systems
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In this article, the authors investigated the resource allocation design for intelligent reflecting surface (IRS)-assisted full-duplex (FD) cognitive radio systems, where an RIS is deployed to enhance the performance of the secondary network while helping to mitigate the interference caused to the primary users (PUs).Abstract:
In this article, we investigate the resource allocation design for intelligent reflecting surface (IRS)-assisted full-duplex (FD) cognitive radio systems. In particular, a secondary network employs an FD base station (BS) for serving multiple half-duplex downlink (DL) and uplink (UL) users simultaneously. An IRS is deployed to enhance the performance of the secondary network while helping to mitigate the interference caused to the primary users (PUs). The DL transmit beamforming vectors and the UL receive beamforming vectors at the FD BS, the transmit power of the UL users, and the phase shift matrix at the IRS are jointly optimized for maximization of the total spectral efficiency of the secondary system. The design task is formulated as a non-convex optimization problem taking into account the imperfect knowledge of the PUs’ channel state information (CSI) and their maximum interference tolerance. Since the maximum interference tolerance constraint is intractable, we apply a safe approximation to transform it into a convex constraint. To efficiently handle the resulting approximated optimization problem, which is still non-convex, we develop an iterative block coordinate descent (BCD)-based algorithm. This algorithm exploits semidefinite relaxation, a penalty method, and successive convex approximation and is guaranteed to converge to a stationary point of the approximated optimization problem. Our simulation results do not only reveal that the proposed scheme yields a substantially higher system spectral efficiency for the secondary system than several baseline schemes, but also confirm its robustness against CSI uncertainty. Besides, our results illustrate the tremendous potential of IRS for managing the various types of interference arising in FD cognitive radio networks.read more
Citations
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Intelligent Reflecting Surface-Aided Wireless Communications: A Tutorial
TL;DR: This paper provides a tutorial overview of IRS-aided wireless communications, and elaborate its reflection and channel models, hardware architecture and practical constraints, as well as various appealing applications in wireless networks.
Journal ArticleDOI
Robust and Secure Wireless Communications via Intelligent Reflecting Surfaces
TL;DR: In this article, the authors investigated the joint design of the beamformers and AN covariance matrix at the AP and the phase shifters at the RISs for maximization of the system sum-rate while limiting the maximum information leakage to the potential eavesdroppers.
Journal ArticleDOI
Two-Timescale Channel Estimation for Reconfigurable Intelligent Surface Aided Wireless Communications
TL;DR: A two-timescale channel estimation framework to exploit the property that the BS-RIS channel is high-dimensional but quasi-static, while the RIS-UE channel is mobile but low-dimensional is proposed.
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Terahertz Massive MIMO With Holographic Reconfigurable Intelligent Surfaces
TL;DR: In this paper, a closed-loop channel estimation (CE) scheme was proposed to estimate the broadband channels that characterize terahertz (THz) massive MIMO systems aided by holographic RISs.
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Intelligent Surfaces for 6G Wireless Networks: A Survey of Optimization and Performance Analysis Techniques
Rawan Alghamdi,Reem Alhadrami,Dalia Alhothali,Heba Almorad,Alice Faisal,Sara Helal,Rahaf Shalabi,Rawan Asfour,Noofa Hammad,Asmaa Shams,Nasir Saeed,Hayssam Dahrouj,Tareq Y. Al-Naffouri,Mohamed-Slim Alouini +13 more
TL;DR: This paper provides a unique blend that surveys the principles of operation of LIS, together with their optimization and performance analysis frameworks, and presents various optimization frameworks that aim to optimize specific objectives, namely, maximizing energy efficiency, sum- rate, secrecy-rate, and coverage.
References
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Journal ArticleDOI
Intelligent Reflecting Surface Enhanced Wireless Network via Joint Active and Passive Beamforming
Qingqing Wu,Rui Zhang +1 more
TL;DR: Simulation results demonstrate that an IRS-aided single-cell wireless system can achieve the same rate performance as a benchmark massive MIMO system without using IRS, but with significantly reduced active antennas/RF chains.
Journal ArticleDOI
Semidefinite Relaxation of Quadratic Optimization Problems
TL;DR: This article has provided general, comprehensive coverage of the SDR technique, from its practical deployments and scope of applicability to key theoretical results, and showcased several representative applications, namely MIMO detection, B¿ shimming in MRI, and sensor network localization.
Proceedings ArticleDOI
Full duplex radios
TL;DR: The design and implementation of the first in-band full duplex WiFi radios that can simultaneously transmit and receive on the same channel using standard WiFi 802.11ac PHYs are presented and achieves close to the theoretical doubling of throughput in all practical deployment scenarios.
Journal ArticleDOI
Convergence of a block coordinate descent method for nondifferentiable minimization
TL;DR: In this article, the convergence properties of a block coordinate descent method applied to minimize a non-convex function f(x1,.., x 2, N 3 ) with certain separability and regularity properties were studied.
Journal ArticleDOI
Towards Smart and Reconfigurable Environment: Intelligent Reflecting Surface Aided Wireless Network
Qingqing Wu,Rui Zhang +1 more
TL;DR: In this paper, the authors provide an overview of the IRS technology, including its main applications in wireless communication, competitive advantages over existing technologies, hardware architecture as well as the corresponding new signal model.
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