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A Joint Rate Control and AMC Algorithm for Adaptive Transmission Systems

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Journal of Harbin Institute of Technology(New Series) 2013年第2期20卷 12-16页

作者： Yang Yu Xue-Zhi Tan Yong-Gang Chi Lin Ma Yao Wang communication research Center Harbin Institute of Technology

The traditional communication system is effectively designed for the worst-case channel state and it can not use the spectral efficiently over the time-varying multipath channel. In order to improve the spectral efficiency and ensure robust and spectrally-efficient transmission over the time-varying multipath channel,a joint rate control and adaptive modulation and coding ( AMC) algorithm for adaptive transmission systems is proposed in this paper. Firstly,the proposed algorithm can formulate a modulation and coding scheme ( MCS) switching table according to the offline simulation results and the target bit error rate ( BER) . Then,the optimal MCS is selected in MCS switching table according to the channel state information ( CSI) and then passes to the transmitter and receiver to implement. So the adaptive system which always uses the optimal MCS to transmit signals uses the spectral efficiently. The simulation results validate the proposed algorithm and show that under the premise of meeting the target BER,the adaptive system performing the proposed algorithm has a higher average spectral efficiency ( ASE) than that of the non-adaptive system.

关键词： adaptive modulation and coding average spectral efficiency adaptive transmission system modulation and coding scheme switching table

Joint channel estimation and beam selection NOMA system for satellite-based Internet of Things

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Science China(Information Sciences) 2022年第10期65卷 270-284页

作者： Zeqiong CHEN Jian JIAO Shaohua WU Qinyu ZHANG communication Engineering research Centre Harbin Institute of Technology (Shenzhen) Peng Cheng laboratory

Multibeam low earth orbit(LEO) millimeter wave(mm Wave) band high throughput satellite(HTS) is regarded as a key component in the upcoming satellite-based Internet of Things(S-Io T). The multibeam LEO HTS with non-orthogonal multiple access(NOMA) can support global coverage and low latency broadband access over a wide geographical area in a cost-efficient manner. However, the performance is constrained by the channel state information and subsequent beam selection in multibeam LEO *** design a joint channel estimation and beam selection NOMA system for S-Io T in this paper, including the pseudo random ergodic(PRE)-throughput maximum(TM) scheme for massive multiple access, and the asynchronous CSI-assisted(AIA)-TM scheme for high throughput services. Moreover, we propose the PREfairness guaranteed(FG) and AIA-FG schemes for achieving better fairness with slightly loss of *** results show that the PRE-TM and AIA-TM schemes can adaptively reduce the required channel measurements, while approaching the optimal system throughput performance of the exhaust searching(ES)scheme with a much lower computational complexity.

关键词： satellite-based Internet of Things non-orthogonal multiple access channel estimation system throughput fairness

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An IP mobility management scheme with dual location areas for IP/LEO satellite network

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Journal of Zhejiang University-Science C(Computers and Electronics) 2012年第5期13卷 355-364页

作者： Zhu ZHANG Qing GUO communication research Center Harbin Institute of TechnologyHarbin 150001China

One of the issues of mobility management in a low Earth orbit (LEO) satellite network is the high-frequency location binding update initiated by mobile nodes (MNs).To solve this problem,we propose a location management scheme based on dual location area (LA) in an IP/LEO satellite *** proposed scheme uses two kinds of LA,the fixed Earth station LA and satellite LA,to manage the location of the MNs *** operate the binding update procedures only when they are moving out of both of the two LAs last *** location information of MN is used in the binding update procedures,so that the network can page the idle MNs near their last registered location first,to enhance the probability of paging success.A detailed description of the implementation of the scheme is *** analysis shows that the proposed scheme reduces the location management cost and minimizes the influences of the distance between MN and its home *** cost is also reduced by introducing geographical location information in the binding update procedures.

关键词： Location management IP/LEO satellite network Mobile IP (MIP) GPS

How to apply polar codes in high throughput space communications

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Science China(Technological Sciences) 2020年第8期63卷 1371-1382页

作者： FENG BoWen JIAO Jian WU ShaoHua ZHANG QinYu communication Engineering research Center Harbin Institute of Technology(Shenzhen)Shenzhen 518055China

This paper describes how to apply polar codes in high-throughput space *** high throughput space communications can enable terabit data rate capacity wideband wireless transmissions,and offer service availability of anywhere and *** paper investigates the channel characteristics in space *** channels are lossy,time-varying,intermittent,long-latency,and with imperfect channel state information(CSI).In order to make the polar codes suitable for the space channel,some improvements and designs on the polar codes are provided in this *** encoding and decoding methods of polar codes are discussed,which are the key to determine the *** describe some rateless polar coding schemes that can guide the construction of suitable codes for time-varying channels with no-CSI in long-haul ***,a high-rate parallel concatenation scheme of polar codes is introduced,which can improve the anti-interrupt ability of polar ***,in order to support the massive connectivity requirements of future space communication networks,polar-coded sparse-code-multiple-access(SCMA)schemes are investigated.

关键词： space communications polar code concatenated coding high throughput

Tumor inflammation-specific self-amplifying fluorescent molecular probes induce an anti-tumor immune response

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Science China Chemistry 2025年第1期 273-287页

作者： Shuguang Yang Lijun Hu Hong Xiao Zecong Xiao Xintao Shuai PCFM lab of Ministry of Education School of Materials Science and Engineering Sun Yat-sen University Department of Ultrasound The Fifth Affiliated Hospital Sun Yat-sen University Department of Medical Ultrasound The Third Affiliated Hospital of Sun Yat-sen University Nanomedicine research Center The Third Affiliated Hospital of Sun Yat-sen University

Enhancing the concentration of exogenous molecular drugs within the tumor microenvironment through enzyme-catalyzed polymerization presents a novel strategy for cancer therapy. Nonetheless, the optimization of the catalytic efficiency is often impeded by the inefficient expression of enzymes. Herein, we reported a self-amplifying fluorescent molecular probe, Bis-HTPICG, for photodynamic therapy(PDT) and subsequent PDT-induced immunoreaction. The Bis-HTP-ICG probe possesses a noticeable enzyme-catalyzed polymerization facilitated by myeloperoxidase(MPO), a crucial enzyme secreted by neutrophils at inflammation sites. Upon exposure to laser irradiation, Bis-HTP-ICG showed a high PDT efficacy, inducing an acute inflammatory response that stimulates further recruitment of neutrophils and then elevated MPO secretion. The heightened level of MPO enhances the accumulation of the Bis-HTP-ICG via self-polymerization or binding with intratumoral proteins following MPO enzyme catalysis, instigating a self-amplifying chain reaction cycle involving Bis-HTP-ICG, neutrophils and ***, PDT efficiently incites immunogenic cell death(ICD) in tumor cells, initiating an anti-tumor immune response including dendritic cells(DCs) maturation, T cell proliferation and reprogramming of tumor-associated neutrophils(TANs). This work portrays a promising strategy for self-amplification of fluorescent molecular probes through adjustable enzyme levels,potentially offering a unique avenue to enhance the tumor accumulation of molecular drugs for improved tumor therapy.

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Magnetic and electrical properties of zincblende CrAs

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Chinese Physics B 2008年第6期17卷 2204-2207页

作者：陈鹏 Takamura K SouthWest University Department of Physics research Institute of Electrical communication Tohoku University

This paper reports that 9nm zincblende CrAs is grown by molecular-beam epitaxy on InAs buffer layer. The zb-CrAs shows ferromagnetism at room temperature and the total magnetic moment 3.09 ±0.15μB per CrAs unit. The... 详细信息

关键词： zincblende molecular-beam epitaxy half-metal

Mathematical Modeling and Design of RIS Deployment in a RIS-Assisted Metal Cuboid for WAIC Systems

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China communications 2023年第4期20卷 86-101页

作者： Hongchi Lin Qiyue Yu communication research Center Harbin Institute of TechnologyHarbin 150000China

Wireless avionics intra-communications(WAIC)is an emergent research topic,since it can improve fuel efficiency and enhance aircraft safety ***,there are numerous baffles in an aircraft,e.g.,seats and cabin bulkheads,resulting in serious blockage and even destroying wireless ***,this paper focuses on the reconfigurable intelligent surface(RIS)deployment issue of RIS-assisted WAIC systems,to solve the blockage problem caused by *** first propose the mirror-symmetric imaging principle for mathematically analyzing electromagnetic(EM)wave propagation in a metal cuboid,which is a typical structure of WAIC *** on the mirror-symmetric imaging principle,the mathematical channel model in a metal cuboid is deduced in *** addition,we develop an objective function of RIS's location and deduce the optimal RIS deployment location based on the geometric center optimization lemma.A two-dimensional gravity center search algorithm is then *** results show that the designed RIS deployment can greatly increase the received power and efficiently solve the blockage problem in the aircraft.

关键词： wireless avionics intra-communications(WAIC) reconfigurable intelligent surface(RIS) channel modeling deployment optimization

Wavelength conversion technique based on self phase modulation in highly nonlinear microstructure fiber

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Optoelectronics Letters 2010年第4期6卷 278-280页

作者：陈明谭艳兰李天松 research Institute of Optical communication School of Information and Communication EngineeringGuilin University of Electronic Technology

A wavelength converter based on the self phase modulation(SPM) effect in highly nonlinear microstructure fibers(MFs) is *** core diameter and the pitch of the fiber are 2.05 μm and 5.0 μm,respectively,and the diameter of the airholes in the fiber cladding is 4.50 μ*** calculating nonlinear coefficient is 112.2 W-1 km-1 and it is 11 times higher than that of a conventional dispersion-shift fiber and 56 times higher than that of a conventional single-mode *** length of the fiber is 100 *** core area of the microstructure fiber is 3.3 μ*** self phase modulation effect is enhanced in the highly nonlinear microstructure fiber due to the very small fiber core area,and then the efficiency of the wavelength conversion is also *** wavelength conversion over ±4 nm is obtained with a good efficiency.

关键词：自相位调制效应微结构光纤非线性系数波长转换技术色散位移光纤纤维长度波长转换效率波长转换器

Design and implementation of scenic-spot introduction-task-oriented3D virtual human spoken dialogue system

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Journal of Beijing Institute of Technology 2014年第3期23卷 395-400页

作者：吴王惠谢湘焦祎姗张征高高 research Institute of communication Technology Beijing Institute of Technology

A scenic-spot introduction-task-oriented 3D virtual human spoken dialogue system-- EasyGuide is introduced. The system includes five modules： natural language processing, task do- main knowledge database, dialogue management, voice processing and 3D virtual human text-to-vis- ual speech synthesis. In the first module, dictionary construction along with sentence analysis and semantic representation axe illustrated specifically. A tree-structured knowledge database is designed for the task domain. A novel framework based on the keyword analysis and context constraints is proposed as the dialogue management. As for voice processing module, a software development kit which performs speech recognition and synthesis is introduced briefly. In the last module, 3D viseme synthesis is explained with examples and a text-driven facial animation system is presented. Evalua- tion results show that the system can achieve satisfactory performance.

关键词： spoken dialogue system speech recognition dialogue management.