检索结果-内蒙古大学图书馆

Learning Optimal Antenna Tilt Control Policies: A Contextual Linear Bandits Approach

IEEE TRANSACTIONS ON MOBILE COMPUTING 2024年第12期23卷 12666-12679页

作者： Vannella, Filippo Proutiere, Alexandre Jedra, Yassir Jeong, Jaeseong Ericsson Res S-16483 Stockholm Sweden KTH Royal Inst Technol Div Decis & Control Syst S-11428 Stockholm Sweden MIT Lab Informat & Decis Syst Cambridge MA 02139 USA

Controlling antenna tilts in cellular networks is critical to achieve a good trade-off between network coverage and capacity. We devise algorithms learning optimal tilt control policies from existing data (passive learning setting) or from data actively generated by the algorithms (active learning setting). We formalize the design of such algorithms as a Best Policy Identification problem in Contextual Linear Bandits (CLB). In CLB, an action represents an antenna tilt update;the context captures current network conditions;the reward corresponds to an improvement of performance, mixing coverage and capacity. The objective is to identify an approximately optimal policy (a function mapping the context to an action with maximal reward). For both active and passive learning, we derive information-theoretical lower bounds on the number of samples required by any algorithm returning an approximately optimal policy with a given level of certainty, and devise algorithms achieving these fundamental limits. We apply our algorithms to the Remote Electrical Tilt optimization problem in cellular networks, and show that they can produce optimal tilt update policy using much fewer data samples than naive or existing rule-based learning algorithms. This paper is an extension of work presented at IEEE International Conference on Computer Communications (INFOCOM) 2022 (Vannella et al. 2022).

关键词： Antennas Optimization approximation algorithms Interference Mobile computing Control systems Context modeling Antenna tilt optimization coverage capacity optimization best policy identification contextual linear bandits

来源：评论

学校读者我要写书评

暂无评论

Joint Admission Control and Power Minimization in IRS-Assisted Networks

引用

IEEE COMMUNICATIONS LETTERS 2025年第3期29卷 512-516页

作者： Xiong, Weijie Lin, Jingran Xiao, Zhiling Li, Qiang Zhang, Yuhan Univ Elect Sci & Technol China Sch Informat & Commun Engn Chengdu 611731 Peoples R China Lab Electromagnet Space Cognit & Intelligent Contr Beijing 100083 Peoples R China Tianfu Jiangxi Lab Chengdu 641419 Sichuan Peoples R China

Joint admission control and power minimization are critical challenges in intelligent reflecting surface (IRS)-assisted networks. Traditional methods often rely on $ l_{1} $ -norm approximations and alternating optimi... 详细信息

Joint admission control and power minimization are critical challenges in intelligent reflecting surface (IRS)-assisted networks. Traditional methods often rely on $ l_approximation $ -norm approximations and alternating optimization (AO) techniques, which suffer from high computational complexity and lack robust convergence guarantees. To address these limitations, we propose a sigmoid-based approximation of the $ l_approximation $ -norm AC indicator, enabling a more efficient and tractable reformulation of the problem. Additionally, we introduce a penalty dual decomposition (PDD) algorithm to jointly optimize beamforming and admission control, ensuring convergence to a stationary solution. This approach reduces computational complexity and supports distributed implementation. Moreover, it outperforms existing methods by achieving lower power consumption, accommodating more users, and reducing computational time.

关键词： Signal to noise ratio Interference Optimization Convergence Minimization Admission control Computational complexity approximation algorithms Linear programming Array signal processing Power minimization admission control IRS non-convex optimization penalty dual decomposition

来源：评论

学校读者我要写书评

暂无评论

Fast Subgraph Matching by Dynamic Graph Editing

引用

IEEE TRANSACTIONS ON SERVICES COMPUTING 2024年第5期17卷 2432-2443页

作者： Jiang, Zite Zhang, Shuai Liu, Boxiao Hou, Xingzhong Yuan, Mengting You, Haihang Chinese Acad Sci Inst Comp Technol SKLP Beijing 100045 Peoples R China Univ Chinese Acad Sci Sch Comp Sci & Technol Beijing 101408 Peoples R China Zhongguancun Lab Beijing 100190 Peoples R China Wuhan Univ Sch Comp Sci Wuhan 430072 Peoples R China

Subgraph matching is a challenging NP-complete problem that involves finding identical subgraphs of a query graph qq in a larger data graph G. It has numerous applications in diverse fields, including social and biological networks. However, existing subgraph matching algorithms assume that the graph structure is fixed, which limits their performance in solving more difficult matching cases. To address this issue, we propose a novel approach called Dynamic Graph Editing (DGE), which dynamically edits the query graph to optimize the subgraph matching algorithm. Based on this approach, we introduce an efficient enumeration method called Dynamic Graph Editing Enumeration, which significantly improves the performance of the algorithm. Our experimental results show that DGE outperforms current state-of-the-art algorithms in terms of computational efficiency and ability to solve more complex subgraph matching cases.

关键词： Heuristic algorithms Optimization Search problems approximation algorithms Social networking (online) Pattern matching Constraint handling Graph algorithm subgraph matching query processing optimization technique

来源：评论

学校读者我要写书评

暂无评论

On the Benefits of Traffic "Reprofiling" the Multiple Hops Case-Part I

引用

IEEE-ACM TRANSACTIONS ON NETWORKING 2024年第4期32卷 3421-3436页

作者： Qiu, Jiaming Song, Jiayi Guerin, Roch Sariowan, Henry Washington Univ St Louis Comp Sci & Engn Dept St Louis MO 63130 USA ByteDance Inc San Jose CA 95110 USA Google Mountain View CA 94043 USA

This paper considers networks where user traffic is regulated through deterministic traffic profiles, e.g. token buckets, and requirescleanguaranteed hard delay bounds. The network's goal is to minimize the resources it needs to meet those cleanrequirementsbounds. The paper explores how reprofiling, i.e. proactively modifying how user traffic enters the network, can be of benefit. Reprofiling produces "smoother" flows but introduces an up-front access delay that forces tighter network delays. The paper explores this trade-off and demonstrates that, unlike what holds in the single-hop case, reprofiling can be of benefit even when "optimal"cleansophisticated schedulers are available at each hop.

关键词： Delays Fluids Upper bound Reviews Calculus approximation algorithms Latency bandwidth optimization shaping network calculus

来源：评论

学校读者我要写书评

暂无评论

FBMC-Based Massive Connectivity With Asynchronous Transmission in Frequency-Selective Fading Channels

引用

IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS 2024年第12期23卷 18951-18968页

作者： Qi, Yuhao Dang, Jian Zhang, Zhentian Zhang, Zaichen Wu, Liang Wu, Yongpeng Southeast Univ Frontiers Sci Ctr Mobile Informat Commun & Secur Natl Mobile Commun Res Lab Nanjing 210096 Peoples R China Purple Mt Labs Nanjing 211111 Peoples R China Shanghai Jiao Tong Univ Dept Elect Engn Shanghai 200240 Peoples R China

The robustness of filter bank multi-carrier (FBMC) against delays is appealing for asynchronous grant-free massive connectivity systems. In this paper, we study the joint activity detection, delay and channel estimation (JADDCE) problem for filter bank multi-carrier (FBMC)-based uplink massive connectivity with asynchronous transmission and frequency-selective fading (FSF) channels. We formulate JADDCE as a compressed sensing (CS) problem to fully exploit the sparsity structure and propose an efficient algorithm based on generalized approximate message passing (GAMP) to solve it. Besides, since parameters such as noise variance and activity probability may not be perfectly known by the receiver, we introduce the expectation maximization (EM) method into the algorithm and derive the updating rules of the unknown parameters. We also utilize the analysis framework based on average mutual information (AMI) to find theoretical upper-bound of the channel estimation performance. Simulation results show satisfying detection and estimation performance of the proposed algorithm under FSF channels. Besides, the channel estimation performance can approach the theoretical upper-bound.

关键词： Receivers Channel estimation Delays approximation algorithms Message passing Estimation Uplink Symbols Internet of Things Filter banks Filter bank multi-carrier (FBMC) massive connectivity activity detection delay and channel estimation generalized approximate message passing (GAMP)

来源：评论

学校读者我要写书评

暂无评论

Performance Analysis of a 2D-MUSIC Algorithm for Parametric Near-Field Channel Estimation

引用

IEEE WIRELESS COMMUNICATIONS LETTERS 2025年第5期14卷 1496-1500页

作者： Gurgunoglu, Doga Kosasih, Alva Ramezani, Parisa Demir, Ozlem Tugfe Bjornson, Emil Fodor, Gabor KTH Royal Inst Technol Sch Elect Engn & Comp Sci S-10044 Stockholm Sweden TOBB ETU Dept Elect Elect Engn TR-06560 Ankara Turkiye Ericsson Res AB Wireless Access Networks SE-16480 Stockholm Sweden

In this letter, we address parametric channel estimation in a multi-user multiple-input multiple-output system within the radiative near-field of the base station array with aperture antennas. We investigate a two-dimensional multiple signal classification algorithm (2D-MUSIC) to estimate both the range and the azimuth angles of arrival for the users' channels, utilizing parametric radiative near-field channel models. We analyze the performance of the algorithm by deriving the Cram & eacute;r-Rao bound (CRB) for parametric estimation, and its effectiveness is compared against the least squares estimator, which is a non-parametric estimator. Numerical results indicate that the 2D-MUSIC algorithm outperforms the least squares estimator. Furthermore, the results demonstrate that the performance of 2D-MUSIC achieves the parametric channel estimation CRB, which shows that the algorithm is asymptotically consistent.

关键词： Channel estimation Antennas Vectors Multiple signal classification Aperture antennas Parametric statistics Lower bound Covariance matrices Azimuth approximation algorithms Radiative near-field aperture antennas MUSIC channel estimation Cram & eacute r-Rao lower bound

来源：评论

学校读者我要写书评

暂无评论

Unified Dense Subgraph Detection: Fast Spectral Theory Based algorithms

引用

IEEE TRANSACTIONS ON KNOWLEDGE AND DATA ENGINEERING 2024年第3期36卷 1356-1370页

作者： Feng, Wenjie Liu, Shenghua Koutra, Danai Cheng, Xueqi Chinese Acad Sci Inst Comp Technol Beijing 100190 Peoples R China Natl Univ Singapore Inst Data Sci Singapore 117602 Singapore Univ Michigan Ann Arbor MI 48109 USA

How can we effectively detect fake reviews or fraudulent links on a website? How can we spot communities that suddenly appear based on users' interactions? And how can we efficiently find the minimum cut in a large graph? All of these are related to the finding of dense subgraphs, a significant primitive problem in graph analysis with extensive applications across various domains. In this paper, we focus on formulating the problem of the densest subgraph detection and theoretically compare and contrast several correlated problems. Moreover, we propose a unified framework, GenDS , for the densest subgraph detection, provide some theoretical analysis based on the network flow and spectral graph theory, and devise simple and computationally efficient algorithms, SpecGDS and GepGDS , to solve it by leveraging the spectral properties and greedy search. We conduct thorough experiments on 40 real-world networks with up to 1.47 billion edges from various domains. We demonstrate that our SpecGDS yields up to 58.6 x speedup and achieves better or approximately equal-quality solutions for the densest subgraph detection compared to the baselines. GepGDS also reveals some properties of generalized eigenvalue problems for the GenDS . Also, our methods scale linearly with the graph size and are proven effective in applications such as finding collaborations that appear suddenly in an extensive, time-evolving co-authorship network.

关键词： approximation algorithms Image edge detection Heuristic algorithms Greedy algorithms Optimization Collaboration Task analysis Algorithm anomaly detection dense subgraph graph spectral theory large graph mining

来源：评论

学校读者我要写书评

暂无评论

Deep SAR Tomography: A Model-Inspired Approach With Learned Sparse Regularizer

引用

IEEE JOURNAL OF SELECTED TOPICS IN APPLIED EARTH OBSERVATIONS AND REMOTE SENSING 2024年 17卷 18870-18881页

作者： Shen, Rong Wang, Mou Hu, Jiangbo Wen, Yanbo Wei, Shunjun Zhang, Xiaoling Fan, Ling Univ Elect Sci & Technol China UESTC Sch Informat & Commun Engn Chengdu 611731 Peoples R China Chengdu Normal Univ Sch Comp Sci Chengdu 611130 Peoples R China

Synthetic aperture radar tomography (TomoSAR) can acquire high resolution in height direction by forming a large synthetic aperture along the tomographic direction. Compressed sensing (CS) is widely utilized in TomoSAR imaging to reduce the costs of data sensing. Nevertheless, traditional CS-based algorithms are limited to computational complexity and the nontrivial parameters' tuning. To address such problems, an efficient unfolded deep shrinkage-thresholding network is proposed for TomoSAR imaging in this article. The proposed method adopts convolutional neural network module to learn a generalized nonlinear sparse transformation operator, showing great benefits in exploring the optimal prior. Besides, the hyperparameters of the optimization framework are learned by end-to-end learning mechanism instead of manual-defined, which obviously improves the efficiency of imaging process. Inspired by residual network, the residual learning is introduced to reconstruction blocks of the proposed imaging network, improving the robustness of the network. In addition, the training dataset is constructed from point cloud data based on TomoSAR imaging principles, enhancing the network's ability to extract structural information. Finally, extensive simulation and measured experimental results show the effectiveness of the proposed method, obtaining high-quality imaging results while maintaining high computational efficiency.

关键词： Imaging Three-dimensional displays Target tracking Matching pursuit algorithms approximation algorithms Tomography Image reconstruction Point cloud compression Iterative algorithms Apertures Compressed sensing (CS) synthetic aperture radar tomography (TomoSAR) shrinkage thresholding unfolded deep neural work

来源：评论

学校读者我要写书评

暂无评论

Optimizing Resource Allocation for Wireless VR Services

引用

IEEE TRANSACTIONS ON SERVICES COMPUTING 2024年第5期17卷 2719-2732页

作者： Wang, Chih-Hang Shi, Yishuo Yang, De-Nian Chen, Chih-Yen Liao, Wanjiun Acad Sinica Inst Informat Sci Taipei City 115201 Taiwan Wenzhou Univ Coll Math & Phys Dept Stat & Informat Sci Wenzhou 325035 Peoples R China Acad Sinica Res Ctr Informat Technol Innovat Taipei 115201 Taiwan Natl Taiwan Univ Dept Elect Engn Taipei 10617 Taiwan

The virtual reality (VR) market is expected to reach 202.7 billion dollars by 2028, at a compound annual growth rate of 24.74% over the forecast period 2023-2028. It motivates innovative VR services in touring, E-commerce, and social activities, and effective VR video streaming becomes essential. However, VR services are envisaged to consume a large amount of bandwidth, but current research primarily focuses on multimedia streaming for each individual user without considering the opportunity of view synthesis for multicast to reduce wireless resource consumption further. In this article, we formulate a new optimization problem VR Content Sharing and Multicasting (VCSM) and prove the NP-hardness. Then, we propose an approximation algorithm, named Efficient View Synthesis and Multicasting (EVSM), to select multicast views and their Modulation and Coding Schemes (MCS) for wireless VR services. Afterward, we extend EVSM to support dynamic user behaviors and increase scalability with distributed mobile edge computing. We also explore the intrinsic properties of view selections to find the optimal solution for regular user deployment. Experiment results show that EVSM can effectively reduce bandwidth consumption for VR services by more than 50%.

关键词： Bandwidth Multicast algorithms Wireless communication Multicast communication Heuristic algorithms approximation algorithms Streaming media Optimization approximation algorithm multicast VR

来源：评论

学校读者我要写书评

暂无评论

Root Tracking for Rate-Distortion: Approximating a Solution Curve With Higher Implicit Multivariate Derivatives

引用

IEEE TRANSACTIONS ON INFORMATION THEORY 2024年第3期70卷 1540-1587页

作者： Agmon, Shlomi Hebrew Univ Jerusalem Sch Comp Sci & Engn IL-9190401 Jerusalem Israel

The rate-distortion curve captures the fundamental tradeoff between compression length and resolution in lossy data compression. However, it conceals the underlying dynamics of optimal source encodings or test channels. We argue that these typically follow a piecewise smooth trajectory as the source information is compressed. These smooth dynamics are interrupted at bifurcations, where solutions change qualitatively. Sub-optimal test channels may collide or exchange optimality there, for example. There is typically a plethora of sub-optimal solutions, which stems from restrictions of the reproduction alphabet. We devise a family of algorithms that exploits the underlying dynamics to track a given test channel along the rate-distortion curve. To that end, we express implicit derivatives at the roots of a non-linear operator by higher derivative tensors. Providing closed-form formulae for the derivative tensors of Blahut's algorithm thus yields implicit derivatives of arbitrary order at a given test channel, thereby approximating others in its vicinity. Finally, our understanding of bifurcations guarantees the optimality of the root being traced, under mild assumptions, while allowing us to detect when our assumptions fail. Beyond the interest in rate distortion, this is an example of how understanding a problem's bifurcations can be translated to a numerical algorithm.

关键词： Bifurcation Rate-distortion Distortion Computational efficiency approximation algorithms Annealing Tensors Rate distortion theory bifurcations differential equations

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：