- 标题
- 摘要
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- 实验方案
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Evaluation of Signal Regeneration Impact on the Power Efficiency of Long-Haul DWDM Systems
摘要： Due to potential economic benefits and expected environmental impact, the power consumption issue in wired networks has become a major challenge. Furthermore, continuously increasing global Internet traffic demands high spectral efficiency values. As a result, the relationship between spectral efficiency and energy consumption of telecommunication networks has become a popular topic of academic research over the past years, where a critical parameter is power efficiency. The present research contains calculation results that can be used by optical network designers and operators as guidance for developing more power efficient communication networks if the planned system falls within the scope of this paper. The research results are presented as average aggregated traffic curves that provide more flexible data for the systems with different spectrum availability. Further investigations could be needed in order to evaluate the parameters under consideration taking into account particular spectral parameters, e.g., the entire C-band.
关键词： DWDM,phase shift keying,differential phase shift keying,power consumption,spectral efficiency,sub-band spacing,WDM networks,single-line rate,optical fibre networks,power efficiency,energy efficiency
更新于2025-09-23 15:22:29
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[IEEE 2020 Systems of Signals Generating and Processing in the Field of on Board Communications - Moscow, Russia (2020.3.19-2020.3.20)] 2020 Systems of Signals Generating and Processing in the Field of on Board Communications - Spectral Efficiency and Information Transfer Rate Over Optical Fibers in Spatial Parallelism
摘要： Spatial parallelism contribution to optical fibers spectral efficiency and to signal transfer rate is being estimated. Parallelism multiplier system parameter is introduced. Using this parameter analytical expressions are constructed to determine the optical fibers spectral efficiency and information transfer rate. Examples of spatial parallelism of optical signal transmission in few-mode and multicore fibers are given.
关键词： spatial parallelism,information transfer rate,optical fiber,spectral efficiency,parallelism multiplier
更新于2025-09-23 15:21:01
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Spectral efficiency optimization for intelligent reflecting surface aided multi-input multi-output terahertz system
摘要： Intelligent reflecting surface (IRS) is considered as a promising application in terahertz (THz) communications since it is able to enhance the THz communication with no additional power consumptions. In this letter, we consider a downlink multi-input multi-output system, where a base station (BS) communicates to a user with the aid of the IRS. Our goal is to optimize the spectral efficiency by designing discrete phase-shifts at the IRS and the precoder at the BS, which is an intractable nonconvex optimization problem. To solve it, we approximate the problem into another form where we maximize the sum of path gains by designing the phase-shifts of the IRS, and we propose a cross-entropy based algorithm to search the optimal IRS phase-shifts matrix. After that, we use the classical singular value decomposition and water-filling solution to design the optimal precoder.
关键词： terahertz (THz) communication,intelligent reflecting surface (IRS),spectral efficiency
更新于2025-09-23 15:21:01
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P-OMP-IR ALGORITHM FOR HYBRID PRECODING IN MILLIMETER WAVE MIMO SYSTEMS
摘要： This paper presents a P-OMP-IR algorithm for the hybrid precoding problem in millimeter wave (mm-Wave) multiple-input multiple-output (MIMO) systems. In the proposed approach, the digital precoding matrix is updated via the orthogonal matching pursuit (OMP) method, and the analog precoding matrix is re?ned column by column using the dominant singular value and corresponding singular vectors of a residual matrix successively. During the re?ning phase of the analog precoding matrix, an extended power method is designed to calculate the dominant singular value and the corresponding left and right singular vectors, which is able to reduce the computational complexity signi?cantly. Simulation results show that the proposed algorithm can not only reduce the residual of the hybrid precoder e?ectively, but also improve the spectral e?ciency consistently.
关键词： millimeter wave,MIMO systems,orthogonal matching pursuit,P-OMP-IR algorithm,spectral efficiency,hybrid precoding
更新于2025-09-23 15:21:01
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Joint Optimization of FeICIC and Spectrum Allocation for Spectral and Energy Efficient Heterogeneous Networks
摘要： Cellular heterogeneous networks (HetNets) with densely deployed small cells can effectively boost network capacity. The co-channel interference and the prominent energy consumption are two crucial issues in HetNets which need to be addressed. Taking the traffic variations into account, this paper proposes a theoretical framework to analyze spectral efficiency (SE) and energy efficiency (EE) considering jointly further-enhanced inter-cell interference coordination (FeICIC) and spectrum allocation (SA) via a stochastic geometric approach for a two-tier downlink HetNet. SE and EE are respectively derived and validated by Monte Carlo simulations. To create spectrum and energy efficient HetNets that can adapt to traffic demands, a non-convex optimization problem with the power control factor, resource partitioning fraction and number of subchannels for the SE and EE tradeoff is formulated, based on which, an iterative algorithm with low complexity is proposed to achieve the sub-optimal solution. Numerical results confirm the effectiveness of the joint FeICIC and SA scheme in HetNets. Meanwhile, a system design insight on resource allocation for the SE and EE tradeoff is provided.
关键词： sleep mode,stochastic geometry,spectral efficiency,spectrum allocation,FeICIC,heterogeneous networks,energy efficiency
更新于2025-09-19 17:15:36
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[IEEE 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Chicago, IL, USA (2019.6.16-2019.6.21)] 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Grid-forming Inverter Experimental Testing of Fault Current Contributions
摘要： This paper concerns with a relay-aided massive multiple input multiple output (MIMO) cellular network. The exact closed-form expressions of both spectral efficiency (SE) and energy efficiency (EE) are obtained for downlink single-cell multi-user multi-relay massive MIMO transmission in the pilot-contaminated regime, where the number of users is larger than the pilot sequence length. Based on the theoretical results of SE and EE, we investigate the effects of some system parameters [such as number of antennas at the base station (BS), transmit power at the BS, and transmit power of each relay station (RS)] on system performance, and achieve the tradeoff between SE and EE by power control. Specifically, the tradeoff problem is solved by joint optimization over transmit power P of the BS and transmit power pr of each RS, so as to maximize EE while satisfying the SE requirement. With the proposition that EE function is strictly quasi-concave with either P or pr, we propose two optimization methods: 1-D searching and alternate optimization. Comparatively, the former achieves a better performance, while the latter has a lower complexity. Simulation results validate the effectiveness of the two methods.
关键词： spectral efficiency,energy efficiency,massive MIMO,Cellular networks,relay
更新于2025-09-19 17:13:59
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Optical polar based MIMO-OFDM with fully generalised index-spatial LED modulation
摘要： A novel efficient visible light communication (VLC) modulation technique teams as polar fully generalised index-spatial (PFGIS) modulation light emitting diode (LED) for the multi-input multi-output (MIMO) optical polar based OFDM (MIMO-POFDM) system is proposed here. The PFGIS is a spectrally efficient (SE) modulation scheme which introduces an elegant solution to tackle the OFDM signal shaping problem, moreover, the PFGIS improves the optical MIMO-OFDM system SE. In the PFGIS, the Cartesian complex OFDM signal is transformed to polar OFDM (POFDM). Then, the indices of the active LEDs are exploited to convey the POFDM signal components. While, the spatial position of the LEDs are exploited as a spatial modulation (SM). In the SM, the LEDs indices used for data transmission are changed from the case of two LEDs are selected to case where all/multiple LEDs are selected. Subsequently, the proposed system achievable data rate is linearly increased with the LEDs number. The PFGIS gives higher SE even with a lower LEDs number compared with the recently OFDM optical LED index modulation techniques. Simulation results confirm the efficiency of the proposed PFGIS in improving both the achievable data rate and the bit error rate compared with the up-to-date LED index modulation OFDM schemes.
关键词： multi-input multi-output (MIMO),spatial modulation (SM),visible light communication (VLC),polar fully generalised index-spatial (PFGIS) modulation,optical polar based OFDM (MIMO-POFDM),spectral efficiency (SE)
更新于2025-09-19 17:13:59
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Spectral-Efficiency -Illumination Pareto Front for Energy Harvesting Enabled VLC Systems
摘要： The continuous improvement in optical energy harvesting devices motivates the development of visible light communication systems that utilize such available free energy. In this paper, an outdoor visible light communications (VLC) system is considered where a VLC base station sends data to multiple users that are capable of harvesting optical energy. The proposed VLC system serves multiple users using time division multiple access (TDMA) with unequal time and power allocation, which are allocated to achieve the system communications and illumination objectives. In an outdoor setup, the system lighting objective is to maximize the average illumination flux, while the communication design objective is to maximize the spectral efficiency (SE). A multiobjective optimization problem is formulated to obtain the Pareto front of the SE-illumination region. To this end, the marginal optimization problems are solved first using low complexity algorithms. Then, based on the proposed algorithms, a Karush-Kuhn-Tucker-based algorithm is developed to obtain an inner bound of the Pareto front for the SE-illumination tradeoff. The inner bound for the Pareto-front is shown to be close to the optimal Pareto-frontier via several simulation scenarios for different system parameters.
关键词： Pareto front,outdoor communication,illumination,multiobjective optimization,mass gathering events,spectral efficiency,energy harvesting,Visible light communication
更新于2025-09-19 17:13:59
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[IEEE 2018 International Conference Laser Optics (ICLO) - St. Petersburg (2018.6.4-2018.6.8)] 2018 International Conference Laser Optics (ICLO) - Spectroscopic and laser properties of Tm <sup>3+</sup> ions optical centers in CaF2-YF3:Tm <sup>3+</sup> solid solutions
摘要： In this paper, we review recent progress on space division multiplexed (SDM) transmission and our proposal of dense SDM (DSDM) with more than 30 spatial channels toward capacities beyond petabit/s. Furthermore, we discuss the requirements for realizing long-haul DSDM transport systems using multicore and/or multimode fiber, including power and space efficient amplification schemes, the use of fibers with large effective areas and transmission lines with low intercore crosstalk, low differential mode delay (DMD), and low mode dependent loss (MDL). Graded index heterogeneous 12-core × 3-mode fiber with low crosstalk, low DMD, and low MDL, parallel multiple-input and multiple-output signal processing, low mode dependent gain Erbium-doped fiber amplifiers, and MDL equalization technologies are significant as regards extending the reach of multicore and multimode transmission. We review our long-distance transmission experiment on polarization-division multiplexed 16-quadrature amplitude modulation signaling over 12-core × 3-mode fiber.
关键词： optical communication systems,optical fibers,optical fiber communication,spectral efficiency,space division multiplexing,Digital signal processing (DSP)
更新于2025-09-19 17:13:59
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[IEEE 2019 18th International Conference on Optical Communications and Networks (ICOCN) - Huangshan, China (2019.8.5-2019.8.8)] 2019 18th International Conference on Optical Communications and Networks (ICOCN) - Coherent Optical Orthogonal Frequency Division Multiplexing with Index Modulation
摘要： CO-OFDM with index modulation is proposed in this paper. Compared with the conventional CO-OFDM systems, the proposed scheme can improve spectral efficiency up to 6.25% with similar transmission performance.
关键词： Index modulation,Spectral efficiency
更新于2025-09-16 10:30:52