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Gamma Approximation Based Multi-Antenna Covert Communication Detection
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作者 Wan Pengwu Chen Dongrui +2 位作者 Wang Danyang Hui Xi Peng Kang 《China Communications》 SCIE CSCD 2024年第9期90-97,共8页
Covert communication technology makes wireless communication more secure,but it also provides more opportunities for illegal users to transmit harmful information.In order to detect the illegal covert communication of... Covert communication technology makes wireless communication more secure,but it also provides more opportunities for illegal users to transmit harmful information.In order to detect the illegal covert communication of the lawbreakers in real time for subsequent processing,this paper proposes a Gamma approximation-based detection method for multi-antenna covert communication systems.Specifically,the Gamma approximation property is used to calculate the miss detection rate and false alarm rate of the monitor firstly.Then the optimization problem to minimize the sum of the missed detection rate and the false alarm rate is proposed.The optimal detection threshold and the minimum error detection probability are solved according to the properties of the Lambert W function.Finally,simulation results are given to demonstrate the effectiveness of the proposed method. 展开更多
关键词 covert communication detection Gamma approximation Lambert W function multi-antenna technique
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Iterative Signal Detection Based Soft Interference Cancellation for Satellite-Terrestrial Downlink NOMA Systems
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作者 Sun Meng Zhang Qi +5 位作者 Yao Haipeng Gao Ran Xin Xiangjun Tian Feng Feng Weiying Chen Dong 《China Communications》 SCIE CSCD 2024年第8期249-263,共15页
To improve the bit error rate(BER)performance of multi-user signal detection in satelliteterrestrial downlink non-orthogonal multiple access(NOMA)systems,an iterative signal detection algorithm based on soft interfere... To improve the bit error rate(BER)performance of multi-user signal detection in satelliteterrestrial downlink non-orthogonal multiple access(NOMA)systems,an iterative signal detection algorithm based on soft interference cancellation with optimal power allocation is proposed.Given that power allocation has a significant impact on BER performance,the optimal power allocation is obtained by minimizing the average BER of NOMA users.According to the allocated powers,successive interference cancellation(SIC)between NOMA users is performed in descending power order.For each user,an iterative soft interference cancellation is performed,and soft symbol probabilities are calculated for soft decision.To improve detection accuracy and without increasing the complexity,the aforementioned algorithm is optimized by adding minimum mean square error(MMSE)signal estimation before detection,and in each iteration soft symbol probabilities are utilized for soft-decision of the current user and also for the update of soft interference of the previous user.Simulation results illustrate that the optimized algorithm i.e.MMSE-IDBSIC significantly outperforms joint multi-user detection and SIC detection by 7.57dB and 8.03dB in terms of BER performance. 展开更多
关键词 non-orthogonal multiple access(NOMA) resource allocation satellite-terrestrial communication signal detection soft interference cancellation
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Potential Transmission Choice for Internet of Things(IoT):Wireless and Batteryless Communications and Open Problems 被引量:4
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作者 Zhan Xu Guanjie Hu +1 位作者 Minzheng Jia Lan Dong 《China Communications》 SCIE CSCD 2021年第2期241-249,共9页
The 5th generation mobile communications aims at connecting everything and future Internet of Things(IoT)will get everything smartly connected.To realize it,there exist many challenges.One key challenge is the battery... The 5th generation mobile communications aims at connecting everything and future Internet of Things(IoT)will get everything smartly connected.To realize it,there exist many challenges.One key challenge is the battery problem for small devices,such as sensors or tags.Batteryless backscatter,also referred to as or battery-free backscatter,is a new potential technology to address this problem.One early and typical type of batteryless backscatter is ambient backscatter.Generally,batteryless backscatter utilizes environmental wireless signals to enable battery-free devices to communicate with each other.These devices first harvest energy from ambient wireless signals and then backscatter these signals so as to transmit their own information.This paper reviews the current studies about batteryless backscatter,including various backscatter schemes and theoretical works,and then introduces open problems for future research. 展开更多
关键词 batteryless backscatter battery-free channel state information(CSI) channel estimation multiple antennas signal detection symbiotic communication
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Evolution of Road Traffic Congestion Control:A Survey from Perspective of Sensing,Communication,and Computation 被引量:1
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作者 Wenwei Yue Changle Li +2 位作者 Guoqiang Mao Nan Cheng Di Zhou 《China Communications》 SCIE CSCD 2021年第12期151-177,共27页
Road traffic congestion can inevitably de-grade road infrastructure and decrease travel efficiency in urban traffic networks,which can be relieved by employing appropriate congestion control.Accord-ing to different de... Road traffic congestion can inevitably de-grade road infrastructure and decrease travel efficiency in urban traffic networks,which can be relieved by employing appropriate congestion control.Accord-ing to different developmental driving forces,in this paper,the evolution of road traffic congestion control is divided into two stages.The ever-growing num-ber of advanced sensing techniques can be seen as the key driving force of the first stage,called the sens-ing stage,in which congestion control strategies ex-perienced rapid growth owing to the accessibility of traffic data.At the second stage,i.e.,the communica-tion stage,communication and computation capabil-ity can be regarded as the identifying symbols for this stage,where the ability of collecting finer-grained in-sight into transportation and mobility reality improves dramatically with advances in vehicular networks,Big Data,and artificial intelligence.Specifically,as the pre-requisite for congestion control,in this paper,ex-isting congestion detection techniques are first elab-orated and classified.Then,a comprehensive survey of the recent advances for current congestion control strategies with a focus on traffic signal control,vehi-cle route guidance,and their combined techniques is provided.In this regard,the evolution of these strate-gies with continuous development of sensing,com-munication,and computation capability are also intro-duced.Finally,the paper concludes with several re-search challenges and trends to fully promote the in-tegration of advanced techniques for traffic congestion mitigation in transportation systems. 展开更多
关键词 road traffic congestion control congestion detection traffic signal control vehicle route guid-ance sensing techniques communication and compu-tation capability
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Signal Detection Algorithm Design Based on Stochastic Resonance Technology Under Low Signal-to-Noise Ratio 被引量:1
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作者 JIANG Xiaolin DIAO Ming QU Susu 《Journal of Shanghai Jiaotong university(Science)》 EI 2019年第3期328-334,共7页
In the current 4th generation(4G)communication network,the base station with the same frequency transmission makes a serious interference among adjacent cells,and information transmission is susceptible to interferenc... In the current 4th generation(4G)communication network,the base station with the same frequency transmission makes a serious interference among adjacent cells,and information transmission is susceptible to interference such as channel multipath fading and occlusion effect.Detecting effectively spectrum signal under low signal-to-noise ratio(SNR),directly affects the whole performance of the wireless communication network system.This paper designs an energy signal detection algorithm based on stochastic resonance technology which transforms noise's signal energy into useful signal energy,and improves output SNR.The energy signal detection algorithm realizes the function of providing effective detection of signal under low SNR,and promotes the performance of the whole communication system. 展开更多
关键词 4G communication network stochastic resonance signal detection algorithm
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160-Gb/s polarization-multiplexing optical NRZ-DQPSK transmission using differential detection
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作者 闻和 廖金鑫 +1 位作者 郑小平 张汉一 《Chinese Optics Letters》 SCIE EI CAS CSCD 2011年第10期30-33,共4页
Using differential detection, we perform polarization-multiplexing 160-Gb/s optical non-return-to-zero (NRZ) differential quadrature phase shift keying (DQPSK) signal transmission over 100-kin standard single mode... Using differential detection, we perform polarization-multiplexing 160-Gb/s optical non-return-to-zero (NRZ) differential quadrature phase shift keying (DQPSK) signal transmission over 100-kin standard single mode fiber at a bit error rate (BER) of less than 10^-9. The enabling technology includes clock recovery, fine dispersion compensation, and polarization tracking for de-multiplexing. Furthermore, a hybrid clock recovery scheme is proposed. The scheme is realized with ordinary devices using an optoelectrical modulator to down-convert the clock frequency and a phase-locked loop for filtering, which can provide an indication signal that simultaneously monitors residual dispersion and tracking polarization. 展开更多
关键词 Bit error rate Electric clocks Error detection MULTIPLEXING Optical communication Phase locked loops POLARIZATION Quadrature phase shift keying signal detection Single mode fibers
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Study of dual-polarization OQAM-OFDM PON with direct detection
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作者 罗清龙 冯敏 +1 位作者 白成林 胡卫生 《Optoelectronics Letters》 EI 2016年第1期65-68,共4页
An offset quadrature amplitude modulation orthogonal frequency-division multiplexing(OQAM-OFDM) passive optical network(PON) architecture with direct detection is brought up to increase the transmission range and impr... An offset quadrature amplitude modulation orthogonal frequency-division multiplexing(OQAM-OFDM) passive optical network(PON) architecture with direct detection is brought up to increase the transmission range and improve the system performance.In optical line terminal(OLT),OQAM-OFDM signals at 40 Gbit/s are transmitted as downstream.At each optical network unit(ONU),the optical OQAM-OFDM signal is demodulated with direct detection.The results show that the transmission distance can exceed 20 km with negligible penalty under the experimental conditions. 展开更多
关键词 Amplitude modulation Frequency division multiplexing Optical fiber communication Passive optical networks Quadrature amplitude modulation signal detection
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A new method of demodulating the digital frequency modulation signals 被引量:2
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作者 Jin-cai Sun Wei-jie Zhu Yi-yun Sun and Hui Xiao 《Journal of Marine Science and Application》 2003年第2期5-10,共6页
A new method of estimating the frequency-known signals from the strong background noise was presented first. Then the new method was used in the demodulation of the digital frequency modulation (FSK) signals. The new ... A new method of estimating the frequency-known signals from the strong background noise was presented first. Then the new method was used in the demodulation of the digital frequency modulation (FSK) signals. The new demodulation method can complete the demodulation of the FSK signals only with the carrier frequency and without any carrier phase information. The simulation results show that the performance of anti-noise of the new method is better than that of the incoherent demodulation method and the fluctuation of the carrier phase has little effect on the new method. So the new demodulation method has a fine prospect in the practical applications. 展开更多
关键词 digital frequency modulation signals underwater acoustic communications DEMODULATION detection
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Exploiting the Faster-Than-Nyquist Concept in Wavelength-Division Multiplexing Systems Using Duobinary Shaping 被引量:1
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作者 Ekawit Tipsuwannakul Magnus Karlsson Peter A. Andrekson 《ZTE Communications》 2012年第1期23-29,共7页
This paper begins with Nyquist wavelengthdivision multiplexing (WDM) and then introduces fasterthanNyquist. In fasterthanNyquist a certain amount of intersymbol interference (ISI) is accepted, which violates the f... This paper begins with Nyquist wavelengthdivision multiplexing (WDM) and then introduces fasterthanNyquist. In fasterthanNyquist a certain amount of intersymbol interference (ISI) is accepted, which violates the fundamental principle of Nyquist WDM. This results in muchrelaxed transceiver bandwidth and simpler spectral design. However, in fasterthanNyquist, implementation complexity is shifted from the transmitter side to the receiver side. Therefore, successful application of fasterthanNyquist depends on innovation in the receiver structure. In this paper, we discuss the guidelines for implementing suboptimum, lowcomplexity receivers based on fasterthanNyquist. We suggest that duobinary shaping is a good technique for trading off achievable spectral efficiency, detection performance, and implementation complexity and might be preferable to Nyquist WDM. Experiments are conducted to verify robustness of the proposed technique. 展开更多
关键词 coherent detection digital signal processing optical fiber communications spectralefficiency wavelength division multiplexing
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A novel repetition space-time coding scheme for mobile FSO systems
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作者 黎明 曹阳 +1 位作者 李书明 杨绍文 《Optoelectronics Letters》 EI 2015年第2期125-129,共5页
Considering the influence of more random atmospheric turbulence, worse pointing errors and highly dynamic link on the transmission performance of mobile multiple-input multiple-output (MIMO) free space optics (FSO... Considering the influence of more random atmospheric turbulence, worse pointing errors and highly dynamic link on the transmission performance of mobile multiple-input multiple-output (MIMO) free space optics (FSO) communica- tion systems, this paper establishes a channel model for the mobile platform. Based on the combination of Alamouti space-time code and time hopping ultra-wide band (TH-UWB) communications, a novel repetition space-time coding (RSTC) method for mobile 2x2 free-space optical communications with pulse position modulation (PPM) is devel- oped. In particular, two decoding methods of equal gain combining (EGC) maximum likelihood detection (MLD) and correlation matrix detection (CMD) are derived. When a quasi-static fading and weak turbulence channel model are considered, simulation results show that whether the channel state information (CSI) is known or not, the coding sys- tem demonstrates more significant performance of the symbol error rate (SER) than the uncoding. In other words, transmitting diversity can be achieved while conveying the information only through the time delays of the modulated signals transmitted from different antennas. CMD has almost the same effect of signal combining with maximal ratio combining (MRC). However, when the channel correlation increases, SER performance of the coding 2×2 system de- grades significantly. 展开更多
关键词 Atmospheric turbulence Broadband networks Channel capacity Channel state information Codes (symbols) communication channels (information theory) Fading channels Iterative decoding Maximum likelihood MIMO systems Optical communication Pulse position modulation Radio communication Random errors signal detection signal encoding Space time adaptive processing Telecommunication networks Time delay Ultra wideband (UWB)
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