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Weighted sum power maximization for STAR-RIS-aided SWIPT systems with nonlinear energy harvesting

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Science China(Information Sciences) 2024年第10期67卷 343-358页

作者： Weiping SHI Cunhua PAN Feng SHU yongpeng wu Jiangzhou WANG Yongqiang BAO Jin TIAN School of Network and Communication Nanjing Vocational College of Information Technology National Mobile Communications Research Laboratory Southeast University School of Information and Communication Engineering Hainan University School of Electronic and Optical Engineering Nanjing University of Science and Technology Shanghai Key Laboratory of Navigation and Location Based Services Shanghai Jiao Tong University School of Engineering University of Kent School of Information and Communication Engineering Nanjing Institute of Technology Engineering School of Networks and Telecommunications Jinling Institute of Technology

The conventional reconfigurable intelligent surface(RIS) is limited to reflecting incident signals,thereby imposing constraints on the placement of the transmitter and receiver, which hinders achieving comprehensive signal coverage across an entire area. This paper investigates a simultaneously transmitting and reflecting(STAR)-RIS-aided simultaneous wireless information and power transfer(SWIPT) system with a nonlinear energy harvesting model under three different RIS transmission protocols: energy splitting(ES),time switching(TS), and mode switching(MS). The objective of this paper is to maximize the weighted sum power(WSP) of all energy harvesting receivers(EHRs) while ensuring fairness in the collected power among them. This is achieved by jointly optimizing the transmit beamforming at the base station(BS)and the transmission and reflection coefficients at the STAR-RIS, subject to rate constraints for information decoding receivers(IDRs), transmit power constraint at the BS, and coefficient constraints of each element at the STAR-RIS corresponding to the three protocols. Solving this optimization problem poses challenges because of the complicated objective function and numerous coupled optimization variables of the ES STAR-RIS. To address this complexity, an efficient alternating optimization(AO) approach is proposed as an iterative solution method that achieves suboptimal results. The AO algorithm is then extended to MS STAR-RIS and TS STAR-RIS. Specifically, for MS STRA-RIS, binary constraints in the STAR-RIS coefficient optimization subproblem are handled using the first-order approximation technique along with the penalty function method. For TS STAR-RIS, apart from optimizing BS transmit beamforming and STAR-RIS coefficients subproblems, the transmission and reflection time allocation of STAR-RIS also needs *** findings demonstrate that compared to conventional RIS-aided systems, utilizing three different protocols in a STAR-RIS-aided sy

关键词： STAR-RIS beamforming SWIPT alternating optimization nonlinear energy harvesting

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共享码本随机接入有限块长信息理论极限分析

中兴通讯技术 2024年第1期30卷 41-45页

作者：高俊园吴泳澎张文军上海交通大学中国上海200240

超大规模机器通信(umMTC)是6G移动通信网络的典型应用场景。针对umMTC场景中的共享码本随机接入问题展开信息理论研究,在给定基站天线数、码长、用户载荷和发送功率的情况下,推导了平均每用户误差概率的非渐近可达界和逆定理。仿真结果... 详细信息

超大规模机器通信(umMTC)是6G移动通信网络的典型应用场景。针对umMTC场景中的共享码本随机接入问题展开信息理论研究,在给定基站天线数、码长、用户载荷和发送功率的情况下,推导了平均每用户误差概率的非渐近可达界和逆定理。仿真结果证实了可达界和逆定理的紧致性,并且证明了当用户数低于某一门限时存在多用户干扰消除效应。基站配置多天线能够显著降低平均每用户误差概率,这对支持大量用户可靠接入具有重要意义。此外,与独立码本随机接入相比,共享码本随机接入在能效性方面更具优势。

关键词：共享码本大规模随机接入有限块长可达界和逆定理

Uplink transmission design for crowded correlated cell-free massive MIMO-OFDM systems

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Science China(Information Sciences) 2021年第8期64卷 127-142页

作者： Junyuan GAO yongpeng wu Yongjian WANG Wenjun ZHANG Fan WEI The Department of Electronic Engineering Shanghai Jiao Tong University The National Computer Network Emergency Response Technical Team/Coordination Center of China

In cell-free massive multiple-input multiple-output(MIMO) orthogonal frequency division multiplexing(OFDM) systems, user equipments(UEs) are served by many distributed access points(APs),where channels are correlated owing to finite angle-delay spread in realistic outdoor wireless propagation environments. Meanwhile, the number of UEs is growing rapidly for future fully networked society. In this paper, we focus on the uplink transmission design in crowded correlated cell-free massive MIMO-OFDM systems with a limited number of orthogonal pilots. For the pilot transmission phase, we identify active UEs based on non-orthogonal pilot phase shift hopping patterns and non-orthogonal adjustable phase shift pilots(APSP). We derive a closed-form expression of mean square error of channel estimation(MSE-CE) and obtain an optimal condition for minimizing MSE-CE. According to this condition, the APSP set allocation scheme is proposed. Furthermore, for the data transmission, the max-min power control algorithm is devised to maximize the minimum spectral efficiency(SE) lower bound among active UEs. Simulation results indicate significant performance gains in terms of MSE-CE for the proposed APSP set allocation scheme. The proposed power control scheme can further improve the minimum SE among active UEs. Hence, they are crucial for crowded correlated cell-free massive MIMO-OFDM systems.

关键词： APSP set allocation cell-free massive MIMO-OFDM correlated channels crowded scenarios power control

Error exponent for concatenated codes in DNA data storage under substitution errors

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Science China(Information Sciences) 2022年第5期65卷 289-290页

作者： Yuxuan SHI Shuo SHAO Xiaohang ZHANG Yongjian WANG yongpeng wu School of Cyber and Engineering Shanghai Jiao Tong University The National Computer Network Emergency Response Technical Team Coordination Center of China Department of Electronic Engineering Shanghai Jiao Tong University

Dear editor,The idea to store information on DNA has gained significant attention, due to the explosion of the demand for current data centers and storage techniques in recent years. DNA molecules are well known for t... 详细信息

关键词： DNA data storage substitution errors concatenated codes error exponent polar codes

Performance Evaluation for Medium Voltage MIMO-OFDM Power Line Communication System

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China Communications 2020年第1期17卷 151-162页

作者： Yingxue Li Min Zhang Wenguang Zhu Mengyuan Cheng Cheng Zhou yongpeng wu Jiangxi Economic Research Institutestate STATE GRIDNanchang 330000China Department of Electrical Engineering Shanghai Jiao Tong UniversityShanghai 200240China

Power line communication(PLC)provides intelligent electrical functions such as power quality measurement,fault surveys,and remote control of electrical *** of research works have been done in low voltage(LV)scenario due to the fast development of in-home *** aim of this paper is to evaluate the link-level performance of a medium voltage(MV)MIMO-OFDM communication system based on transmission link under underground power line *** MIMO channel is modeled as a modified multipath model in the presence of impulsive noise and background *** first perform a measurement on the practical MV MIMO channel parameters for a section of buried cable of 1 km long in Ganzhou city,Jiangxi province,*** on the measured channel,we design the frame structure based on an IEEE standard for broadband over power line networks[1]to support MV MIMO-OFDM *** to designed frame structure,we design an encoder and a decoder for a dual binary tail-biting turbo code and optimize some key decoder parameters for low bit error rate ***,the link-level performance for both spatial multiplexing and spatial diversity are *** results show that MV MIMO-OFDM is a promising approach to provide both high data rate and link reliability for PLC.

关键词： power line communication(PLC) MIMO-OFDM multi-conductor medium voltage underground cables turbo code

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高温环境对防弹插板抗弹性能影响分析

兵器装备工程学报 2024年第2期45卷 94-99页

作者：聂嘉兴程时雨李忠盛黄安畏郭峰林禹李鹏吴永鹏中国兵器工业第五九研究所重庆400039

采用M80弹(7.62 mm×51 mm NATO)分别对常温和高温(55℃)下的防弹插板进行实弹射击试验,以研究高温环境对防弹插板抗弹性能的影响。通过分析试验时防弹插板弹击瞬间凹陷值,同时结合聚氨酯树脂的剥离强度、超高分子量聚乙烯纤维层压板剥... 详细信息

采用M80弹(7.62 mm×51 mm NATO)分别对常温和高温(55℃)下的防弹插板进行实弹射击试验,以研究高温环境对防弹插板抗弹性能的影响。通过分析试验时防弹插板弹击瞬间凹陷值,同时结合聚氨酯树脂的剥离强度、超高分子量聚乙烯纤维层压板剥离强度和弯曲强度的测试结果对高温下抗弹性能变化原因进行了研究。结果表明:高温下防弹插板抗弹性能明显下降,相对于常温下每发弹的弹击瞬间凹陷值增加了2~5 mm。其主要原因是超高分子量聚乙烯纤维层压板在高温下抵抗变形的能力发生明显下降,从而导致防弹插板的弹击瞬间凹陷值增大。

关键词：防弹插板弹击瞬间凹陷值高温环境超高分子量聚乙烯纤维层压板

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基于多址接入的多任务语义通信编码框架

移动通信 2024年第2期48卷 70-76页

作者：林航吴泳澎施雨轩许铭楷张文军上海交通大学电子信息与电气工程学院上海200240

语义通信作为一种新兴的通信范式,在提高通信传输效率等方面具有潜力。基于此,在语义通信背景下结合多址接入与多任务学习,提出了一个在多址接入场景下可以实现多个下游任务执行的语义通信框架MAMTSC,使用联合信源信道编码器与联合信源... 详细信息

语义通信作为一种新兴的通信范式,在提高通信传输效率等方面具有潜力。基于此,在语义通信背景下结合多址接入与多任务学习,提出了一个在多址接入场景下可以实现多个下游任务执行的语义通信框架MAMTSC,使用联合信源信道编码器与联合信源信道-任务解码器在用户与用户之间、任务与任务之间复用语义信息,提高传输效率。该框架设计了能够处理多种下游任务的多址接入网络,并在两用户、语义分割和深度估计的图像语义通信场景中进行仿真实验,通过和速率-失真的表现验证了其有效性。在低信噪比情况下,提出的方案相比于传统编码方法在语义分割的平均交并比参数上,最多可取得18%的提升。

关键词：语义通信多址接入多任务学习

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风力发电机机舱新型接闪系统防护效能评估

科技资讯 2024年第6期22卷 95-98,151页

作者：吴永鹏王甜甜于雪原杨航何相勇中车山东风电有限公司山东济南250022 西安爱邦电磁技术有限责任公司陕西西安710199

针对风力发电机复材机舱接闪系统防护效能评估中存在的滚球法适用受限、被保护对象结构与分布复杂的问题,结合风电场雷电环境特点,建立了两种接闪设计方案的数值模型,计算了多种先导起点位置条件下的电场分布;从表面电场、附着区域及等... 详细信息

针对风力发电机复材机舱接闪系统防护效能评估中存在的滚球法适用受限、被保护对象结构与分布复杂的问题,结合风电场雷电环境特点,建立了两种接闪设计方案的数值模型,计算了多种先导起点位置条件下的电场分布;从表面电场、附着区域及等电势覆盖区域3个关键影响因素出发,比较了两种设计方案的防护效果,结果表明:该方法能够更加准确评估防护效能,可有效支持复杂系统的雷电防护的精细化设计。

关键词：防护效能评估方法接闪系统风力发电机组

A Preamble-Based MAC Mechanism in Ad-Hoc Network

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Journal of Communications and Information Networks 2022年第1期7卷 60-71页

作者： Chenchao Shi Biqian Feng yongpeng wu Wenjun Zhang Department of Electronic Engineering Shanghai Jiao Tong UniversityShanghai 200240China

In this paper, we propose a preamble-based medium access control (P-MAC) mechanism in Ad-Hoc *** from traditional carrier sense multiple access(CSMA)in Ad-Hoc network,P-MAC uses a much shorter preamble to establish the network. First, we propose the P-MAC mechanism to shorten the time of establishing the Ad-Hoc network. Based on the P-MAC, we propose a more efficient way to maintain the network. Next, focusing on the power line communication (PLC) network which is a kind of Ad-Hoc network,we propose a frequency division power line communication (FD-PLC) network architecture to obtain the best communication frequency. To obtain the best frequency, i.e., highest signal-to-noise ratio (SNR), we design the frequency sweeping mechanism which can determine the frequency of uplink and downlink communication before the transmitter and receiver communicate. Due to the large-scale networks in industry,P-MAC can be exploited to speed up the establishment of the Ad-Hoc PLC network. Finally, we compare our mechanism with CSMA. Numerical results indicate that our strategy greatly shortens the time of establishing the Ad-Hoc network.

关键词： P-MAC Ad-Hoc network CSMA PLC