Joint Diagnosis of RIS and BS for RIS-Aided Millimeter-Wave System

Ma, Siqi; Li, Jianguo; Bu, Xiangyuan; An, Jianping

doi:10.3390/electronics10202556

Cited by 7 publications

(4 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In addition to element failures resulting from internal hardware imperfections, RIS element blockages due to external environmental effects such as dust, rain and ice have been studied in recent works [26], [27]. In [26], blockages at both the BS and RIS are considered and an iterative algorithm is proposed to jointly estimate the blockage coefficients of the BS and RIS. In [27], the authors propose a two-stage algorithm for joint RIS diagnosis and channel estimation in a RIS-aided mmWave MIMO system.…”

Section: B Related Work On Failuresmentioning

confidence: 99%

RIS-aided Localization under Pixel Failures

Ozturk¹,

Keskin²,

Sciancalepore³

et al. 2023

Preprint

View full text Add to dashboard Cite

Reconfigurable intelligent surfaces (RISs) hold great potential as one of the key technological enablers for beyond-5G wireless networks, improving localization and communication performance under line-of-sight (LoS) blockage conditions. However, hardware imperfections might cause RIS elements to become faulty, a problem referred to as pixel failures, which can constitute a major showstopper especially for localization. In this paper, we investigate the problem of RIS-aided localization of a user equipment (UE) under LoS blockage in the presence of RIS pixel failures, considering the challenging single-input singleoutput (SISO) scenario. We first explore the impact of such failures on accuracy through misspecified Cramér-Rao bound (MCRB) analysis, which reveals severe performance loss with even a small percentage of pixel failures. To remedy this issue, we develop two strategies for joint localization and failure diagnosis (JLFD) to detect failing pixels while simultaneously locating the UE with high accuracy. The first strategy relies on 1regularization through exploitation of failure sparsity. The second strategy detects the failures one-by-one by solving a multiple hypothesis testing problem at each iteration, successively enhancing localization and diagnosis accuracy. Simulation results show significant performance improvements of the proposed JLFD algorithms over the conventional failure-agnostic benchmark, enabling successful recovery of failure-induced performance degradations.

show abstract

Section: B Related Work On Failuresmentioning

confidence: 99%

RIS-aided Localization under Pixel Failures

Ozturk¹,

Keskin²,

Sciancalepore³

et al. 2023

Preprint

View full text Add to dashboard Cite

show abstract

“…After the cooperative time slots are determined in Step 2, the transmit beamforming vectors associated with the cooperative time slots are updated. In line (15), N c is the number of cooperative time slots, which can be determined as a minimum value of either Count 1 or Count 2 .…”

Section: Proposed Algorithmmentioning

confidence: 99%

“…Estimation methods for wireless channels with RISs are being actively studied [ 15 , 16 , 17 , 18 , 19 , 20 ]. However, it is difficult to estimate the channels between BS-RIS and RIS-UE separately.…”

Section: Ris-assisted Cooperative Time-division Multiple Accessmentioning

confidence: 99%

“…Crucially, these algorithms relied on precise channel state information (CSI) for the link from BS to UE across the RIS. There is much research on channel estimation in RIS-assisted systems, but it is worth noting that channel estimation still has many difficulties and issues for practical implementation, such as its accuracy, computational complexity, and overhead [ 15 , 16 , 17 , 18 , 19 , 20 ].…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

RIS-Assisted Cooperative Time-Division Multiple Access

Son,

Kwon

2023

Sensors

View full text Add to dashboard Cite

Reconfigurable intelligent surface-aided communication systems have been intensively investigated to improve capacity, coverage, and energy efficiency via optimal controlling of phase shifts for passive reflecting elements. However, there are few studies on cooperative transmission incorporating RIS in TDMA systems, because RIS reflects all the incident signals, and it inadvertently leads to a boost in interference signals. In this paper, we propose RIS-assisted cooperative time-division multiple access, in which the required SINR of all users is guaranteed as much as possible by opportunistic use of RIS for cooperative transmission. The proposed scheme’s primary function is that some time slots, i.e., cooperative time slots, serve a pair of users, i.e., a strong- and a weak-channel-conditioned user, using RIS. To support this functionality, we propose scheduling for non-cooperative and cooperative time slots, user pairing for scheduled cooperative time slots, and transmit beamforming vector design for the pair of UEs in each cooperative time slot. The simulation and numerical results demonstrate that the proposed scheme guarantees QoS for all UE as much as possible and minimizes the remaining required capacity indicating the amount of capacity that was not achieved compared with the required capacity.

show abstract