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Chinese Journal of Lasers 1999年第4期8卷 3-5页

作者： YAO Minyu ZHANG Jianfeng WU Jian CHEN Minghua WANG Dapeng LOU Caiyun GAO Yizhi ZHOU Bingkun (Department of Electronic Engineering, Tsinghua University, Beijing 100084, China) Received Sep. 24, 1998 Revised manuscript received Jan. 22, 1999 清华大学电子工程系北京 100084 清华大学电子工程系北京

It is presented the experiment of all optical demultiplexing of one 2.5 Gb/s channel from an 8×2.5 Gb/s OTDM data stream using nonlinear optical loop morror with 3 km dispersion shifted fiber. bit error rate (BER) of the demultiplexed channel is measured. A BER of 10 -11 is achieved and the power penalty is only 1.4 dB when BER is 10 -9 .

关键词： optical time division multiplexing demultiplexing nonlinear optical loop mirror bit error rate

The Genetic Algorithm in the Minimum bit error rate Multi-User Detection Assisted Space Division Multiple Access System

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The Genetic Algorithm in the Minimum Bit Error Rate Multi-Us...

Underwater wireless optical NOMA communication experiment system exploiting GaN-based micro-LED array grouping

2011 International Conference on Internet Computing and Information Services （ICICIS 2011）

作者： Jean-Baptiste YAMINDI Wu Mu-qing Institute School of Information and Telecommunication Engineering Beijing University of Posts and Telecommunications

This is a recent research on Space Division Multiple Access-Orthogonal Frequency Division Multiplexing（SDMA-OFDM） based on the biological technique of Genetic Algorithm（GA） which is reminiscent of the rules of evolution and survival where a group of fitters’ individuals in a population will survive more and more using in the wireless communication in the Multi-User Detection. The goal of this research is using Genetic Algorithm assisted by Minimum bit error rate（MBER） comparatively of the Conjugate Graduate（CG） method to MultiUser Detection on OFDM due to the technique using the symbol chromosomes to obtain an initial Frequency Domain-CHannel Transfer Function（FD-CHTF） assisted by Minimum bit error rate that the GA is capable of approaching the MBER solution at a lower complexity than the CG algorithm and it can be achieved by the simulation results provided to demonstrate the improvement of Multi-User Detection using Genetic Algorithm assisted by Minimum bit error rate.

关键词： Multi-User bit error rate chromosome detection graduate

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Chinese Optics Letters 2024年第3期22卷 1-6页

作者：梁彦军殷洪玺黄安季秀阳王建英 School of Information and Communication Engineering Dalian University of TechnologyDalian 116024China

This paper has proposed an experimental system for non-orthogonal multiple access(NOMA)wireless optical communication in challenging underwater turbulent environments,employing the gallium nitride(GaN)-based micro-LED *** design of the GaN-based micro-LED array enables the independent transmission of signals from distinct data streams within the NOMA framework,facilitating direct optical power-domain superposition of NOMA *** experimental setup involves emulating oceanic turbulence channels,characterized by varying the level of scintillation intensity,to thoroughly investigate the bit error rate(BER)*** outcomes unequivocally demonstrate the superiority of our proposed NOMA scheme,as compared to conventional circuit-driven optical NOMA systems utilizing fixed LED array grouping,particularly in the presence of turbulent underwater *** proposed NOMA scheme exhibits consistently superior BER performance and maintains excellent linearity at the lower frequencies while effectively mitigating signal distortion at the higher frequencies.

关键词： optical non-orthogonal multiple access gallium nitride-based micro-LED array oceanic turbulence channels bit error rate

Security-Enhanced Directional Modulation Based on Two-Dimensional M-WFRFT

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China Communications 2024年第5期21卷 229-248页

作者： Zhou Zhuang Luo Junshan Wang Shilian Xia Guojiang School of Electronic Science National University of Defense TechnologyChangsha 410073China Beijing Institute of Astronautical Systems Engineering Beijing 100076China

Directional modulation(DM)is one of the most promising secure communication ***,when the eavesdropper is co-located with the legitimate receiver,the conventional DM has the disadvantages of weak anti-scanning capability,anti-deciphering capability,and low secrecy *** response to these problems,we propose a twodimensional multi-term weighted fractional Fourier transform aided DM scheme,in which the legitimate receiver and the transmitter use different transform terms and transform orders to encrypt and decrypt the confidential *** order to further lower the probability of being deciphered by an eavesdropper,we use the subblock partition method to convert the one-dimensional modulated signal vector into a twodimensional signal matrix,increasing the confusion of the useful *** results demonstrate that the proposed DM scheme not only provides stronger anti-deciphering and anti-scanning capabilities but also improves the secrecy rate performance of the system.

关键词： bit error rate directional modulation phased array secrecy rate weighted fractional Fourier transform

Performance Analysis of the Reconfigurable Intelligent Surfaces Communication Systems

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Journal of Communications and Information Networks 2024年第2期9卷 184-191页

作者： Omar Abu Ella Department of Electrical and Electronic Engineering Misurata University2659 Zawiat AlmahjoubMisurataLibya

Reconfigurable intelligent surfaces (RIS) play a vital role in meeting the growing demand for higher data rates and reliability in wireless systems. This study focuses on analyzing the performance of RIS systems to gain a deeper understanding of their *** paper presents a mathematical analysis of the RIS system,deriving closed-form formulae that express its characteristics including signal-to-noise ratio(SNR)distribution,ergodic and effective capacity,outage,and error probability. The obtained formulae are newly derived and unconditionally valid solutions. Numerical results demonstrate a close agreement between the derived formulae and MonteCarlo simulation outcomes.

关键词： ergodic capacity effective capacity outage probability bit error rate Rayleigh fading channel RISassisted communication system

Optical Space Time Pulse Position Modulation over Exponential Weibull Turbulence Channel

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Chinese Journal of Electronics 2024年第2期33卷 527-535页

作者： Yue ZHANG Huiqin WANG Xuemei MA Minghua CAO Qingbin PENG School of Computer and Communication Lanzhou University of Technology School of Foreign Languages Lanzhou University of Technology

An optical space time pulse position modulation(OSTPPM) scheme is proposed to satisfy the communication requirement of high transmission rate and better reliability. For the OSTPPM scheme, an improved threshold judgment-based orthogonal matching pursuit(IT-OMP) algorithm with low-complexity and near optimal performance is proposed. The average bit error rate of OSTPPM-IT-OMP scheme is investigated over the exponential Weibull channel, and its analytical expression is verified via Monte Carlo simulation. With the same simulation parameters, the signal to noise ratio of(4,4,2)-OSTPPM-IT-OMP is respectively 3.75 d B and 8.5 d B better than that of spatial pulse position modulation(SPPM) scheme and generalized spatial pulse position modulation(GSPPM)scheme at a bit error rate of 1 × 10-3. With the same transmission bits per symbol, the computational complexity of(3,4,2)-OSTPPM-IT-OMP scheme is reduced by 90.47% and 75.4% compared with(16,4,2)-SPPM and(5,4,2)-GSPPM schemes, respectively.

关键词： Wireless communication Wireless sensor networks Monte Carlo methods bit error rate Matching pursuit algorithms Adaptive optics Optical modulation

A Design of 2-Stage Voltage Ramp-Up SRAM Physical Unclonable Function

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Chinese Journal of Electronics 2024年第2期33卷 371-379页

作者： Minte SONG Nan LIU Shuaiyang ZHOU Zhengguang WANG Zhanqiang RU Peng DING Wei HUANG Helun SONG School of Nano-Tech and Nano-Bionics University of Science and Technology of China Suzhou Institute of Nano-Tech and Nano-Bionics Chinese Academy of Sciences

Silicon physical unclonable function（PUF） implemented by static random access memory（SRAM）exists inherent demerit of unstable cells due to noise of environment and circuits, which significantly restricts its reproducibility. In this paper, a 16T SRAM cell with reset-delay circuit and a 2-stage voltage ramp up is fabricated and reported. Compared to conventional SRAM structure, each PUF cell adds a pair of pull-up PMOS（P-channel metal oxide semiconductor） and pull-down NMOS（N-channel metal oxide semiconductor） controlled by reset and delayedreset signals respectively, resulting in two positive feedback stages with different amplification coefficients when the voltage is ramped up. PUF array consists of 4064 cells, 322 dummy cells and a group of 8 series-connected inverters with an area of 304 μm × 650 μm to match the digital post-processing module. PUF test chip was fabricated in HHGrace 110 nm platform with total area 1140 × 1140 μm2. The average HDintra（intra-chip Hamming distance, also bit error rate, BER） and HDinter（inter-chip Hamming distance） values of the 50 PUF chips in SOP16 package measured at normal point（1.5 V/25 ℃） were 1.92% and 49.85%, respectively.

关键词： Semiconductor device measurement Circuits bit error rate Metals Aging Physical unclonable function Reproducibility of results

100-Gb/s undersea transmission with high spectral efficiency using pre-filtered QPSK modulation format

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Chinese Optics Letters 2010年第9期8卷 831-836页

作者： J.-X. Cai Y. Cai C. R. Davidson D. G. Foursa A. Lucero O. Sinkin W. Patterson A. Pilipetskii G. Mohs Neal S. Bergano Tyco Electronics Subsea Communications LLC ("TE SubCom" formerly known as ~co Telecommunications (US) Inc.) 250 Industrial Way West Eatontown NJ 07724 USA

We provide a review of our recent 100-Gb/s, high spectral efficiency （SE） experiment targeting transoceanic and regional undersea transmission distances. We demonstrated that simple pre-filtering at the transmitter together with a maximum a posteriori probability （MAP） detection algorithm can significantly improve SE. We transmitted 96×100-Gb/s pre-filtered polarization division multiplexed return-to-zero quadrature phase shift keyed （PDM-RZ-QPSK） channels with 300% SE over 10608 km using 52-km spans of 150-μm 2 fiber and simple single-stage erbium-doped fiber amplifiers （EDFAs）. We also achieved 400% SE over 4368 km using similar techniques.

关键词： bit error rate Erbium doped fiber amplifiers Modulation Optical signals Quadrature phase shift keying Signal processing

Multichannel wavelength multicasting for two QPSK signals based on FWM in SOA

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Chinese Optics Letters 2015年第1期13卷 10-16页

作者：秦军纪越峰王宏祥王丹石张民吕国伟 State Key Laboratory of Information Photonics and Optical Communication School of Information and Communication Engineering Beijing University of Posts and Telecommunications Institute of Innovative Science and Technology Tokai University

We experimentally demonstrate multichannel wavelength multicasting for two nonreturn-to-zero quadrature phase-shift keying （NRZ-QPSK） channels based on four-wave mixing （FWM） in semiconductor optical amplifier （SOA）. Through the interaction with the two pumps in SOA, the input two 25 Gb/s NRZ-QPSK channels are successfully simultaneously multicast to five and two new wavelengths, respectively. All the multicast channels are with a power penalty less than 2.5 dB at a bit error rate （BER） of 10^- 3. A characterization of the system performance using conversion efficiency and BER as figures-of-merit in terms of pump and signal powers is also presented. The results indicate that the pump and signal powers can be optimized to eliminate the introduced deleterious nonlinear components. The wavelengths of the two NRZ-QPSK channels and the two pumps need to be specified to avoid the crosstalk induced by high-order FWM.

关键词： bit error rate Four wave mixing Light amplifiers Multicasting Phase shift Phase shift keying Phase shifters Semiconductor optical amplifiers

Performance analysis of MIMO systems with arbitrary number transmit antenna selection and OSTBC in the presence of imperfect CSI

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Science China(Information Sciences) 2016年第8期59卷 164-179页

作者： Xiangbin YU Xiang-Gen XIA Shuhung LEUNG Department of Electronic Engineering Nanjing University of Aeronautics and Astronautics Department of Electrical and Computer Engineering University of Delaware Department of Electronic Engineering City University of Hong Kong State Key Laboratory of Millimeter Waves City University of Hong Kong

In this paper, the performance analysis of MIMO systems with arbitrary number transmit antenna selection(TAS) and orthogonal space-time block coding(STBC) in Rayleigh fading channels for imperfect channel state information(CSI) is presented. For the performance analysis, the moment generating function of the system effective SNR as well as its upper and lower bounds are derived. Then, accurate and approximate expressions of bit error rate(BER) of MIMO-TAS-STBC with MPSK and MQAM are further derived. Using the approximate BER formula and imperfect CSI, an adaptive antenna selection scheme is developed for minimizing the BER. The diversity gain and coding gain are analyzed at high SNR. The results indicate that the MIMOTAS-STBC for imperfect CSI can only achieve partial diversity order K N and the coding gain is affected by K,N, code rate, modulation pattern, and channel correlation coefficients, when K transmit antennas are selected and N receive antennas are used. Simulation results show that the theoretical analysis matches the simulation result well, and the approximate expressions are close to the accurate ones but have a lower complexity.

关键词： MIMO arbitrary number antenna selection imperfect CSI space-time block coding diversity gain bit error rate