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A Practical Regular LDPC Coded Scheme for Physical-Layer Information Security
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作者 Du Junyi 《China Communications》 SCIE CSCD 2024年第5期190-201,共12页
In this paper,we aim to design a practical low complexity low-density parity-check(LDPC)coded scheme to build a secure open channel and protect information from eavesdropping.To this end,we first propose a punctured L... In this paper,we aim to design a practical low complexity low-density parity-check(LDPC)coded scheme to build a secure open channel and protect information from eavesdropping.To this end,we first propose a punctured LDPC coded scheme,where the information bits in a codeword are punctured and only the parity check bits are transmitted to the receiver.We further propose a notion of check node type distribution and derive multi-edge type extrinsic information transfer functions to estimate the security performance,instead of the well-known weak metric bit error rate.We optimize the check node type distribution in terms of the signal-to-noise ratio(SNR)gap and modify the progressive edge growth algorithm to design finite-length codes.Numerical results show that our proposed scheme can achieve a lower computational complexity and a smaller security gap,compared to the existing scrambling and puncturing schemes. 展开更多
关键词 extrinsic information transfer function physical layer scheme secure open channel security gap
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DPAL-BERT:A Faster and Lighter Question Answering Model
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作者 Lirong Yin Lei Wang +8 位作者 Zhuohang Cai Siyu Lu Ruiyang Wang Ahmed AlSanad Salman A.AlQahtani Xiaobing Chen Zhengtong Yin Xiaolu Li Wenfeng Zheng 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第10期771-786,共16页
Recent advancements in natural language processing have given rise to numerous pre-training language models in question-answering systems.However,with the constant evolution of algorithms,data,and computing power,the ... Recent advancements in natural language processing have given rise to numerous pre-training language models in question-answering systems.However,with the constant evolution of algorithms,data,and computing power,the increasing size and complexity of these models have led to increased training costs and reduced efficiency.This study aims to minimize the inference time of such models while maintaining computational performance.It also proposes a novel Distillation model for PAL-BERT(DPAL-BERT),specifically,employs knowledge distillation,using the PAL-BERT model as the teacher model to train two student models:DPAL-BERT-Bi and DPAL-BERTC.This research enhances the dataset through techniques such as masking,replacement,and n-gram sampling to optimize knowledge transfer.The experimental results showed that the distilled models greatly outperform models trained from scratch.In addition,although the distilled models exhibit a slight decrease in performance compared to PAL-BERT,they significantly reduce inference time to just 0.25%of the original.This demonstrates the effectiveness of the proposed approach in balancing model performance and efficiency. 展开更多
关键词 DPAL-BERT question answering systems knowledge distillation model compression BERT Bi-directional long short-term memory(BiLSTM) knowledge information transfer PAL-BERT training efficiency natural language processing
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High-Power Simultaneous Wireless Information and Power Transfer: Injection-Locked Magnetron Technology 被引量:1
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作者 YANG Bo MITANI Tomohiko +1 位作者 SHINOHARA Naoki ZHANG Huaiqing 《ZTE Communications》 2022年第2期3-12,共10页
Applications using simultaneous wireless information and power transfer(SWIPT)have increased significantly.Wireless communication technologies can be combined with the Internet of Things to develop many innovative app... Applications using simultaneous wireless information and power transfer(SWIPT)have increased significantly.Wireless communication technologies can be combined with the Internet of Things to develop many innovative applications using SWIPT,which is mainly based on wireless energy harvesting from electromagnetic waves used in communications.Wireless power transfer that uses magnetrons has been developed for communication technologies.Injection-locked magnetrons that can be used to facilitate high-power SWIPT for several devices are reviewed in this paper.This new technology is expected to pave the way for promoting the application of SWIPT in a wide range of fields. 展开更多
关键词 simultaneous wireless information and power transfer wireless power transfer MAGNETRONS injection⁃locked Internet of Energy Internet of Things
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Scalable Quantum Information Transfer between Individual Nitrogen-Vacancy Centers by a Hybrid Quantum Interface
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作者 裴培 黄鹤飞 +1 位作者 郭彦青 宋鹤 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第2期9-12,共4页
We develop a design of a hybrid quantum interface for quantum information transfer (QIT), adopting a nanome- chanical resonator as the intermedium, which is magnetically coupled with individual nitrogen-vacancy cent... We develop a design of a hybrid quantum interface for quantum information transfer (QIT), adopting a nanome- chanical resonator as the intermedium, which is magnetically coupled with individual nitrogen-vacancy centers as the solid qubits, while eapacitively coupled with a coplanar waveguide resonator as the quantum data bus. We describe the Hamiltonian of the model, and analytically demonstrate the QIT for both the resonant interaction and large detuning cases. The hybrid quantum interface allows for QIT between arbitrarily selected individual nitrogen-vacancy centers, and has advantages of the sealability and controllability. Our methods open an alter- native perspective for implementing QIT, which is important during quantum storing or processing procedures in quantum computing. 展开更多
关键词 of for is in Scalable Quantum information Transfer between Individual Nitrogen-Vacancy Centers by a Hybrid Quantum Interface by
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The Image Property in an EIT Information Transfer System
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作者 张丽昀 胡华杰 +5 位作者 杨欣 曹明涛 卫栋 张沛 高宏 李福利 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第12期58-62,共5页
We focus on the study of the transferred image property in an electromagnetically induced transparency (EIT)system. In our experiment, a triple-peak image is effectively transferred trom a coupling beam to a signal ... We focus on the study of the transferred image property in an electromagnetically induced transparency (EIT)system. In our experiment, a triple-peak image is effectively transferred trom a coupling beam to a signal beam based on the FIT effect. It is found that the transferred image intensity profile of the signal beam is the same as that of the coupling beam while not in phase. Furthermore, the propagation property of the transferred image is studied. Due to the narrowing effect, the transferred image keeps narrowing and maintains the shape well within a certain distance outside of the medium. Our experimental results are in excellent agreement with the theoretical analysis. 展开更多
关键词 EIT In on for The Image Property in an EIT information Transfer System of in
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Efficient scheme for entangled states and quantum information transfer with trapped atoms in a resonator
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作者 李蓬勃 李福利 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第9期49-53,共5页
A protocol is proposed to generate atomic entangled states and implement quantum information transfer in a cavity quantum electrodynamics system. It utilizes Raman transitions or stimulated Raman adiabatic passages be... A protocol is proposed to generate atomic entangled states and implement quantum information transfer in a cavity quantum electrodynamics system. It utilizes Raman transitions or stimulated Raman adiabatic passages between two systems to entangle the ground states of two three-state A-type atoms trapped in a single mode cavity. It does not need the measurements on cavity field nor atomic detection and can be implemented in a deterministic fashion. Since the present protocol is insensitive to both cavity decay and atomic spontaneous emission, it may have some interesting applications in quantum information processing. 展开更多
关键词 cavity quantum electrodynamics entangled states quantum information transfer
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Speeding up transmissions of unknown quantum information along Ising-type quantum channels
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作者 郭伟杰 韦联福 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第1期125-130,共6页
Quantum teleportation with entanglement channels and a series of two-qubit SWAP gates between the nearestneighbor qubits are usually utilized to achieve the transfers of unknown quantum state from the sender to the di... Quantum teleportation with entanglement channels and a series of two-qubit SWAP gates between the nearestneighbor qubits are usually utilized to achieve the transfers of unknown quantum state from the sender to the distant receiver. In this paper, by simplifying the usual SWAP gates we propose an approach to speed up the transmissions of unknown quantum information, specifically including the single-qubit unknown state and two-qubit unknown entangled ones,by a series of entangling and disentangling operations between the remote qubits with distant interactions. The generic proposal is demonstrated specifically with experimentally-existing Ising-type quantum channels without transverse interaction; liquid NMR-molecules driven by global radio frequency electromagnetic pulses and capacitively-coupled Josephson circuits driven by local microwave pulses. The proposal should be particularly useful to set up the connections between the distant qubits in a chip of quantum computing. 展开更多
关键词 unknown quantum information transfers Ising-type quantum chains NMR molecules superconducting circuits
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Scheme for realizing quantum computation and quantum information transfer with superconducting qubits coupling to a 1D transmission line resonator
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作者 施振刚 谌雄文 +1 位作者 朱喜香 宋克慧 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第3期910-914,共5页
This paper proposes a simple scheme for realizing one-qubit and two-qubit quantum gates as well as multiqubit entanglement based on de-SQUID charge qubits through the control of their coupling to a 1D transmission lin... This paper proposes a simple scheme for realizing one-qubit and two-qubit quantum gates as well as multiqubit entanglement based on de-SQUID charge qubits through the control of their coupling to a 1D transmission line resonator (TLR). The TLR behaves effectively as a quantum data-bus mode of a harmonic oscillator, which has several practical advantages including strong coupling strength, reproducibility, immunity to 1/f noise, and suppressed spontaneous emission. In this protocol, the data-bus does not need to stay adiabatically in its ground state, which results in not only fast quantum operation, hut also high-fidelity quantum information processing. Also, it elaborates the transfer process with the 1D transmission line. 展开更多
关键词 dc-SQUID charge qubits 1D transmission line resonator quantum logic gates quantum information transfer
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Simultaneous wireless information and power transfer with fixed and adaptive modulation
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作者 Jie Hu Guangming Liang +2 位作者 Qin Yu Kun Yang Xiaofeng Lu 《Digital Communications and Networks》 SCIE CSCD 2022年第3期303-313,共11页
Activating Wireless Power Transfer (WPT) in Radio-Frequency (RF) to provide on-demand energy supply to widely deployed Internet of Everything devices is a key to the next-generation energy self-sustainable 6G network.... Activating Wireless Power Transfer (WPT) in Radio-Frequency (RF) to provide on-demand energy supply to widely deployed Internet of Everything devices is a key to the next-generation energy self-sustainable 6G network. However, Simultaneous Wireless Information and Power Transfer (SWIPT) in the same RF bands is challenging. The majority of previous studies compared SWIPT performance to Gaussian signaling with an infinite alphabet, which is impossible to implement in any realistic communication system. In contrast, we study the SWIPT system in a well-known Nakagami-m wireless fading channel using practical modulation techniques with finite alphabet. The attainable rate-energy-reliability tradeoff and the corresponding rationale are revealed for fixed modulation schemes. Furthermore, an adaptive modulation-based transceiver is provided for further expanding the attainable rate-energy-reliability region based on various SWIPT performances of different modulation schemes. The modulation switching thresholds and transmit power allocation at the SWIPT transmitter and the power splitting ratios at the SWIPT receiver are jointly optimized to maximize the attainable spectrum efficiency of wireless information transfer while satisfying the WPT requirement and the instantaneous and average BER constraints. Numerical results demonstrate the SWIPT performance of various fixed modulation schemes in different fading conditions. The advantage of the adaptive modulation-based SWIPT transceiver is validated. 展开更多
关键词 Simultaneous wireless information and power transfer(SWIPT) Fixed/adaptive modulation Rate-energy-reliability trade-off Transceiver design Energy self-sustainability
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Bidirectional transfer of quantum information for unknown photons via cross-Kerr nonlinearity and photon-number-resolving measurement
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作者 Jino Heo Chang-Ho Hong +1 位作者 Dong-Hoon Lee Hyung-Jin Yang 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第2期82-92,共11页
We propose an arbitrary controlled-unitary (CU) gate and a bidirectional transfer scheme of quantum information (BTQI) for unknown photons. The proposed CU gate utilizes quantum non-demolition photon-number-resolv... We propose an arbitrary controlled-unitary (CU) gate and a bidirectional transfer scheme of quantum information (BTQI) for unknown photons. The proposed CU gate utilizes quantum non-demolition photon-number-resolving measure- ment based on the weak cross-Kerr nonlinearities (XKNLs) and two quantum bus beams; the proposed CU gate consists of consecutive operations of a controlled-path gate and a gathering-path gate. It is almost deterministic and is feasible with current technology when a strong amplitude of the coherent state and weak XKNLs are employed. Compared with the existing optical multi-qubit or controlled gates, which utilize XKNLs and homodyne detectors, the proposed CU gate can increase experimental realization feasibility and enhance robustness against decoherence. According to the CU gate, we present a BTQI scheme in which the two unknown states of photons between two parties (Alice and Bob) are mutually swapped by transferring only a single photon. Consequently, by using the proposed CU gate, it is possible to experimentally implement the BTQI scheme with a certain probability of success. 展开更多
关键词 cross-Kerr nonlinearity quantum non-demolition photon-number-resolving measurement bidirec-tional transfer of quantum information
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Programmable Metasurface for Simultaneously Wireless Information and Power Transfer System
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作者 CHANG Mingyang HAN Jiaqi +4 位作者 MA Xiangjin XUE Hao WU Xiaonan LI Long CUI Tiejun 《ZTE Communications》 2022年第2期48-62,共15页
Implementing self-sustainable wireless communication systems is urgent and challenging for 5G and 6G technologies.In this paper,we elaborate on a system solution using the programmable metasurface(PMS)for simultaneous... Implementing self-sustainable wireless communication systems is urgent and challenging for 5G and 6G technologies.In this paper,we elaborate on a system solution using the programmable metasurface(PMS)for simultaneous wireless information and power transfers(SWIPT),offering an optimized wireless energy management network.Both transmitting and receiving sides of the proposed solution are presented in detail.On the transmitting side,employing the wireless power transfer(WPT)technique,we present versatile power conveying strategies for near-field or far-field targets,single or multiple targets,and equal or unequal power targets.On the receiving side,utilizing the wireless energy harvesting(WEH)technique,we report our work on multi-functional rectifying metasurfaces that collect the wirelessly transmitted energy and the ambient energy.More importantly,a numerical model based on the plane-wave angular spectrum method is investigated to accurately calculate the radiation fields of PMS in the Fresnel and Fraunhofer regions.With this model,the efficiencies of WPT between the transmitter and the receiver are analyzed.Finally,future research directions are discussed,and integrated PMS for wireless information and wireless power is outlined. 展开更多
关键词 programmable metasurface simultaneously wireless information and power transfers wireless energy harvesting wireless power transfer
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Certification Institutions Expected to Update and Transfer Information on Present Standards
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作者 Zeng Jiansan He Yanfeng 《China Standardization》 2008年第1期24-25,共2页
  Standards are the basis for production enterprises to organize production, ex-factory inspection, trade (delivery) and technical exchanges, product certification, quality arbitration and supervision.……
关键词 In Certification Institutions Expected to Update and Transfer information on Present Standards
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An Analysis of the Mode of Information Transfer in High-context Cultures in Terms of Red Cliff
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作者 王静 《海外英语》 2020年第1期188-190,共3页
According to Edward Hall,cultures can be categorized as being either high or low context.Chinese culture is typically high-context culture.The paper tries to explore the mode of information transfer in high-context cu... According to Edward Hall,cultures can be categorized as being either high or low context.Chinese culture is typically high-context culture.The paper tries to explore the mode of information transfer in high-context cultures in terms of Red Cliff.The discussion will be focused on dialogues and the costume.This will help understand the characteristics of high-context culture and make the communication between people from cultures of different contexts easier. 展开更多
关键词 high-context culture information transfer Edward Hall
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Multi-Sinusoidal Waveform Shaping for Integrated Data and Energy Transfer in Aging Channels 被引量:1
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作者 Jie Hu Yaping Hou Kun Yang 《China Communications》 SCIE CSCD 2023年第4期243-258,共16页
Integrated data and energy transfer(IDET)is capable of simultaneously delivering on-demand data and energy to low-power Internet of Everything(Io E)devices.We propose a multi-carrier IDET transceiver relying on superp... Integrated data and energy transfer(IDET)is capable of simultaneously delivering on-demand data and energy to low-power Internet of Everything(Io E)devices.We propose a multi-carrier IDET transceiver relying on superposition waveforms consisting of multi-sinusoidal signals for wireless energy transfer(WET)and orthogonal-frequency-divisionmultiplexing(OFDM)signals for wireless data transfer(WDT).The outdated channel state information(CSI)in aging channels is employed by the transmitter to shape IDET waveforms.With the constraints of transmission power and WDT requirement,the amplitudes and phases of the IDET waveform at the transmitter and the power splitter at the receiver are jointly optimised for maximising the average directcurrent(DC)among a limited number of transmission frames with the existence of carrier-frequencyoffset(CFO).For the amplitude optimisation,the original non-convex problem can be transformed into a reversed geometric programming problem,then it can be effectively solved with existing tools.As for the phase optimisation,the artificial bee colony(ABC)algorithm is invoked in order to deal with the nonconvexity.Iteration between the amplitude optimisation and phase optimisation yields our joint design.Numerical results demonstrate the advantage of our joint design for the IDET waveform shaping with the existence of the CFO and the outdated CSI. 展开更多
关键词 integrated data and energy transfer(IDET) wireless energy transfer(WET) simultaneous wireless information and power transfer(SWIPT) carrier-frequency-offset(CFO) WAVEFORM aging channels outdated channel state information(CSI) orthogonal frequency division multiplexing(OFDM)
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Analysis of LDPC Code in Hybrid Communication Systems
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作者 Hasnain Kashif Muhammad Nasir Khan Zubair Nawaz 《Computers, Materials & Continua》 SCIE EI 2023年第1期769-781,共13页
Free-space optical(FSO)communication is of supreme importance for designing next-generation networks.Over the past decades,the radio frequency(RF)spectrum has been the main topic of interest for wireless technology.Th... Free-space optical(FSO)communication is of supreme importance for designing next-generation networks.Over the past decades,the radio frequency(RF)spectrum has been the main topic of interest for wireless technology.The RF spectrum is becoming denser and more employed,making its availability tough for additional channels.Optical communication,exploited for messages or indications in historical times,is now becoming famous and useful in combination with error-correcting codes(ECC)to mitigate the effects of fading caused by atmospheric turbulence.A free-space communication system(FSCS)in which the hybrid technology is based on FSO and RF.FSCS is a capable solution to overcome the downsides of current schemes and enhance the overall link reliability and availability.The proposed FSCS with regular low-density parity-check(LDPC)for coding techniques is deliberated and evaluated in terms of signal-to-noise ratio(SNR)in this paper.The extrinsic information transfer(EXIT)methodology is an incredible technique employed to investigate the sum-product decoding algorithm of LDPC codes and optimize the EXIT chart by applying curve fitting.In this research work,we also analyze the behavior of the EXIT chart of regular/irregular LDPC for the FSCS.We also investigate the error performance of LDPC code for the proposed FSCS. 展开更多
关键词 Free-space communication system low-density parity-check errorcorrecting codes extrinsic information transfer
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Adaptive Time Slot Resource Allocation in SWIPT IoT Networks
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作者 Yunong Yang Yuexia Zhang Zhihai Zhuo 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第9期2787-2813,共27页
The rapid advancement of Internet of Things(IoT)technology has brought convenience to people’s lives;however further development of IoT faces serious challenges,such as limited energy and shortage of network spectrum... The rapid advancement of Internet of Things(IoT)technology has brought convenience to people’s lives;however further development of IoT faces serious challenges,such as limited energy and shortage of network spectrum resources.To address the above challenges,this study proposes a simultaneous wireless information and power transfer IoT adaptive time slot resource allocation(SIATS)algorithm.First,an adaptive time slot consisting of periods for sensing,information transmission,and energy harvesting is designed to ensure that the minimum energy harvesting requirement ismet while the maximumuplink and downlink throughputs are obtained.Second,the optimal transmit power and channel assignment of the system are obtained using the Lagrangian dual and gradient descent methods,and the optimal time slot assignment is determined for each IoT device such that the sum of the throughput of all devices is maximized.Simulation results show that the SIATS algorithm performs satisfactorily and provides an increase in the throughput by up to 14.4%compared with that of the fixed time slot allocation(FTS)algorithm.In the case of a large noise variance,the SIATS algorithm has good noise immunity,and the total throughput of the IoT devices obtained using the SIATS algorithm can be improved by up to 34.7%compared with that obtained using the FTS algorithm. 展开更多
关键词 Internet of Things simultaneous wireless information and power transfer ADAPTIVE time slot resource allocation
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System Outage Probability and Diversity Analysis of a SWIPT Based Two-Way DF Relay Network Under Transceiver Hardware Impairments
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作者 Guangyue Lu Zhipeng Liu +1 位作者 Yinghui Ye Xiaoli Chu 《China Communications》 SCIE CSCD 2023年第10期120-135,共16页
This paper investigates the system outage performance of a simultaneous wireless information and power transfer(SWIPT)based two-way decodeand-forward(DF)relay network,where potential hardware impairments(HIs)in all tr... This paper investigates the system outage performance of a simultaneous wireless information and power transfer(SWIPT)based two-way decodeand-forward(DF)relay network,where potential hardware impairments(HIs)in all transceivers are considered.After harvesting energy and decoding messages simultaneously via a power splitting scheme,the energy-limited relay node forwards the decoded information to both terminals.Each terminal combines the signals from the direct and relaying links via selection combining.We derive the system outage probability under independent but non-identically distributed Nakagami-m fading channels.It reveals an overall system ceiling(OSC)effect,i.e.,the system falls in outage if the target rate exceeds an OSC threshold that is determined by the levels of HIs.Furthermore,we derive the diversity gain of the considered network.The result reveals that when the transmission rate is below the OSC threshold,the achieved diversity gain equals the sum of the shape parameter of the direct link and the smaller shape parameter of the terminalto-relay links;otherwise,the diversity gain is zero.This is different from the amplify-and-forward(AF)strategy,under which the relaying links have no contribution to the diversity gain.Simulation results validate the analytical results and reveal that compared with the AF strategy,the SWIPT based two-way relaying links under the DF strategy are more robust to HIs and achieve a lower system outage probability. 展开更多
关键词 decode-and-forward relay diversity gain hardware impairments simultaneous wireless information and power transfer system outage probability
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UAV-Aided Data and Energy Integrated Network: System Design and Prototype Development
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作者 Xinyu Fan Jie Hu Kun Yang 《China Communications》 SCIE CSCD 2023年第7期290-302,共13页
Terminal devices deployed in outdoor environments are facing a thorny problem of power supply.Data and energy integrated network(DEIN)is a promising technology to solve the problem,which simultaneously transfers data ... Terminal devices deployed in outdoor environments are facing a thorny problem of power supply.Data and energy integrated network(DEIN)is a promising technology to solve the problem,which simultaneously transfers data and energy through radio frequency signals.State-of-the-art researches mostly focus on theoretical aspects.By contrast,we provide a complete design and implementation of a fully functioning DEIN system with the support of an unmanned aerial vehicle(UAV).The UAV can be dispatched to areas of interest to remotely recharge batteryless terminals,while collecting essential information from them.Then,the UAV uploads the information to remote base stations.Our system verifies the feasibility of the DEIN in practical applications. 展开更多
关键词 data and energy integrated network(DEIN) internet of things(IoT) simultaneous wire-less information and power transfer(SWIPT) wireless energy transfer(WET) prototype
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Secure Beamforming Design for SWIPT in Cooperative D2D Communications 被引量:5
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作者 Li Jiang Cheng Qin +1 位作者 Xixi Zhang Hui Tian 《China Communications》 SCIE CSCD 2017年第1期20-33,共14页
In device-to-device(D2D) communications, device terminal relaying makes it possible for devices in a network to function as transmission relays for each other to enhance the spectral efficiency. In this paper we consi... In device-to-device(D2D) communications, device terminal relaying makes it possible for devices in a network to function as transmission relays for each other to enhance the spectral efficiency. In this paper we consider a cooperative D2D communication system with simultaneous wireless information and power transfer(SWIPT). The cooperative D2D communication scheme allows two nearby devices to communicate with each other in the licensed cellular bandwidth by assigning D2D transmitters as half-duplex(HD) relay to assists cellular downlink transmissions. In particular, we focus on secure information transmission for the cellular users when the idle D2D users are the potential eavesdroppers. We aim to design secure beamforming schemes to maximize the D2D users data rate while guaranteeing the secrecy rate requirements of the cellular users and the minimum required amounts of power transferred to the idle D2D users. To solve this non-convex problem, a semi-definite programming relaxation(SDR) approach is adopted to obtain the optimal solution. Furthermore, we propose two suboptimal secure beamforming schemes with low computational complexity for providing secure communication and efficient energy transfer. Simulation results demonstrate the superiority of our proposed scheme. 展开更多
关键词 device-to-device(D2D) communications half-duplex relaying physical layer security secure beamforming simultaneous wireless information and power transfer
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Optimized LDPC differential-encoded 16QAM scheme for high-speed transmission systems 被引量:1
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作者 Zhanji Wu Xiang Gao Zhiyu Xiao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2014年第5期728-734,共7页
The 16-ary quadrature amplitude modulation (16QAM) is a high spectral efficient scheme for high-speed transmission systems. To remove the phase ambiguity in the coherent detection system, differential-encoded 16QAM ... The 16-ary quadrature amplitude modulation (16QAM) is a high spectral efficient scheme for high-speed transmission systems. To remove the phase ambiguity in the coherent detection system, differential-encoded 16QAM (DE-16QAM) is usually used, however, it will cause performance degradation about 3 dB as compared to the conventional 16QAM. To overcome the performance loss, a serial concatenated system with outer low density parity check (LDPC) codes and inner DE-16QAM is proposed. At the receiver, joint iterative differential demodulation and decoding (ID) is carried out to approach the maximum likelihood performance. Moreover, a genetic evolution algorithm based on the extrinsic information transfer chart is proposed to optimize the degree distribution of the outer LDPC codes. Both theoretical analyses and simulation results indicate that this algorithm not only compensates the performance loss, but also obtains a significant performance gain, which is up to 1 dB as compared to the conventional non-DE-16QAM. 展开更多
关键词 quadrature amplitude modulation (QAM) low density parity check (LDPC) code genetic evolution (GE) algorithm iterative demodulation and decoding (ID) extrinsic information transfer (EXIT) chart.
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