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Adaptive modulation in MIMO optical wireless communication systems

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Journal of Southeast University(English Edition) 2015年第2期31卷 175-180页

作者：吴斌吴亮邹采荣东南大学信息科学与工程学院南京210096

In the intensity modulation and direct detection （IM/DD） multiple-input multiple-output （MIMO） optical wireless communication systems, a direct-current-biased adaptive modulation scheme is proposed to guarantee the nonnegative property of transmitted signals, and the MIMO channel is converted to a parallel channel by using a singular value decomposition. Besides, a QR decomposition and successive interference cancellation based adaptive modulation scheme is proposed, and the MIMO channel can be simplified to a parallel channel under the bit error ratio （BER） target constraint. The power is optimally allocated to each sub-channel to maximize the data rate. Simulation results show that the proposed adaptive modulation schemes can effectively improve the transmission rate of the systems under the BER target and constant optical power constraints. The proposed adaptive modulation schemes make use of the multiplexing gain of the MIMO techniques, and can further improve the spectrum efficiency of optical wireless systems.

关键词： optical wireless communication multiple inputand multiple output (MIMO) adaptive modulation

Energy saving for data centers using spatial multichannel optical wireless communication

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Journal of communications and Information Networks 2017年第4期2卷 88-99页

作者： Judy Kupferman Shlomi Arnon Ben Gurion University of the Negev Beer-Sheva 8410501Israel

Data centers are crucial elements in modern information *** order to implement the next generation of data centers,new challenges must be *** include reducing the energy consumption,increasing the data rates,reducing the communication latency,increasing the flexibility and scalability,and reducing the maintenance time and *** promising way for meeting these challenges is to employ multichannel optical wireless communication as part of the data center hybrid communication *** this paper,we analyze three technologies that could be used in this context:MIMO(Multiple-in-Multipleout),multiplexing through orbital angular momentum of light,and direct modulation through the large number of modes associated with orbital angular *** results indicate that these technologies could provide an innovative and flexible means of meeting the challenges of the next generation of data centers.

关键词： data center orbital angular momentum optical wireless communication energy consumption

Indoor optical wireless communication System Using FDPIM

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Indoor Optical Wireless Communication System Using FDPIM

Petahertz communication:Harmonizing optical spectra for wireless communications

2009 ISECS International Colloquium on Computing, communication, Control, and Management

作者： Li Xingguang,Chen Dianren,Cui Wei Chang Chun University of Science and Technology,Chang Chun,China

The performance of Fixed-length Digital Pulse Interval Modulation(FDPIM) in diffuse infrared indoor environment is *** work is based on the ceiling bounce channel model(fig.3) with M = 4,Rb = 166Mbit/s Symbol *** results show FDPIM do not need symbol synchronization and has fixed symbol length,can simplify the receiver and solve modulator waiting or buffer overflow in comparison with PPM and DPIM *** FDPIM has its advantages in wireless optical communications networks.

关键词： optical wireless communication Fixed-length digital pulse position modulation Packet error rate

来源： cnki会议评论

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cnki会议

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Digital communications and Networks 2021年第4期7卷 605-614页

作者： Zhengyuan Xu Weijie Liu Zhaocheng Wang Lajos Hanzo wireless-optical communications Key Laboratory of CAS University of Science and Technology of ChinaHefei230027China Department of Electronic Engineering Tsinghua UniversityBeijing100084China School of Electronics and Computer Science University of SouthamptonSouthamptonS0171BJUK

With the rapid deployment of Next-Generation Networks(NGN),the research community has initiated discussions on an entirely new suite of optical enabling *** pave the way for the development of future wireless networks,this article aims to unify the existing infrared,visible light,and ultraviolet subbands while also exploring the potential of the Petahertz(PHz)band to support extremely bandwidth-thirsfy telepresence style *** focus is on the emerging Petahertz communication(PetaCom)framework,scenario-dependent propagation channels,modulation schemes,system performance,multiple access techniques,and *** conclude with a range of PetaCom challenges and open research issues.

关键词： Petahertz communication Petahertz spectrum harmonization optical spectrum optical wireless communication

Advances and prospects in visible light communications

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Journal of Semiconductors 2016年第1期37卷 1-10页

作者：陈弘达吴春晖李洪磊陈雄斌高宗余崔世钢王琴 State Key Laboratory on Integrated Optoelectronics Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China Tianjin University of Technology and Education Tianjin 300222China Renmin University of China Beijing 100872China

Visible light communication （VLC） is an emerging technology in optical wireless communication （OWC） that has attracted worldwide research in recent years. VLC can combine communication and illumina- tion together, which could be applied in many application scenarios such as visible light communication local area networks （VLANs）, indoor localization, and intelligent lighting. In recent years, pioneering and significant work have been made in the field of VLC. In this paper, an overview of the recent progress in VLC is presented. We also demonstrate our recent experiment results including bidirectional 100 Mbit/s VLAN or Li-Fi system based on 00K modulation without blue filter. The VLC systems that we proposed are good solutions for high-speed VLC application systems with low-cost and low-complexity. VLC technology shows a bright future due to its inherent advantages, shortage of RF spectra and ever increasing popularity of white LEDs.

关键词： white LEDs visible light communication optical wireless communication Li-Fi system OOK equalization

Anisotropy effect on multi-Gaussian beam propagation in turbulent ocean

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Chinese Optics Letters 2018年第8期16卷 6-11页

作者： Yalqln Ata Yahya Baykal TUBiTAK Defense Industries Research and Development Institute （T（JBiTAK SAGE） P.K. 16 Mamak 06261 Ankara Turkey ankaya University Department of Electrical-Electronics Engineering Yukar~yurtgu mah. Mimar Sinan cad. 06790 Ankara Turkey

Average transmittance of multi-Gaussian （flat-topped and annular） optical beams in an anisotropic turbulent ocean is examined analytically based on the extended Huygens-Fresnel principle. Transmittance variations depending on the link length, anisotropy factor, salinity and temperature contribution factor, source size, beam flatness order of fiat-topped beam, Kolmogorov microscale length, rate of dissipation of turbulent kinetic energy, rate of dissipation of the mean squared temperature, and thickness of annular beam are examined. Results show that all these parameters have effects in various tbrms on the average transmittance in an anisotropic turbulent ocean. Hence, the performance of optical wireless communication systems can be improved by taking into ac- count the variation of average transmittance versus the above parameters.

关键词： Huygens Fresnel principle Light beams Oceanic propagation optical wireless communication Spatial frequency Wave propagation

Ultraviolet communication technique and its application

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Journal of Semiconductors 2021年第8期42卷 32-44页

作者： Liang Guo Yanan Guo Junxi Wang Tongbo Wei Research and Development Center for Semiconductor Lighting Technology Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China Beijing Engineering Research Center for the 3rd Generation Semiconductor Materials and Application Beijing 100083China

With recent developments of deep ultraviolet(DUV)light-emitting diodes and solar-blind detectors,UV communication(UVC)shows great potential in replacing traditional wireless communication in more and more *** on the atmospheric scattering of UV radiation,UVC has gained considerable attention due to its non-line-of-sight ability,omnidirectional communication links and low background *** advantages make UVC an ideal option for covert secure communication,especially for military *** this review,we present the history and working principle of UVC with a special focus on its light sources and *** comparison and application of its light sources and detectors are provided to the best of our *** further discuss the future application and outlook of ***,this review will offer valuable insights into the future development of UVC.

关键词： ultraviolet communication non-line-of-sight optical wireless communication

Timing Synchronization Method for Asymmetrically Clipped DC Biased optical OFDM System

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Optics and Photonics Journal 2016年第8期6卷 14-18页

作者： Yong Wang College of Information & communication Engineering Harbin Engineering University Harbin China

In a typical intensity-modulated direct-detection optical system, the information is carried on the intensity of the optical signal, and therefore can only be positive. Existing synchronization methods for RF-based OFDM system cannot be used directly in asymmetrically clipped DC biased optical of DM (ADO-OFDM) system. In order to solve the above problem, according to the characteristics of ADO-OFDM signal, the modified training symbol is presented. The simulation results show that the modified synchronization method gives good performance.

关键词： optical wireless communication ADO-OFDM Timing Synchronization