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oe1(光电查) - 科学论文

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?? 中文(中国)
  • [IEEE 2018 41st International Conference on Telecommunications and Signal Processing (TSP) - Athens, Greece (2018.7.4-2018.7.6)] 2018 41st International Conference on Telecommunications and Signal Processing (TSP) - Studying an Optimal Approach to Design Combined Fiber-Wireless Telecom Systems

    摘要: We proposed a new approach to design interface hardware for next-generation telecom systems of combined fiber-wireless architecture based on nonlinear behavioral modeling in widespread off-the-shelf CAD tool NI AWRDE. To validate the approach, we research in detail a prospective base station operating in EU-assigned band (3.4-3.8 GHz) of 5G networks, which has easy-to-configure layout using the same cost- and power-efficient LW-VCSEL in downlink and uplink channels and direct modulation of LW-VCSEL in period-doubling state.

    关键词: fronthaul fiber-wireless architecture,vertical cavity surface-emitting laser,base station,fifth-generation telecom network,computer-aided design

    更新于2025-09-23 15:22:29

  • Passive Optical Network Based Mobile Backhaul Enabling Ultra-Low Latency for Communications Among Base Stations

    摘要: Low latency is of key importance for mobile networks to support emerging time-critical applications, such as road traffic safety and efficiency. Meanwhile, a passive optical network (PON) is widely recognized as a promising solution for mobile backhaul networks thanks to its high capacity and low energy consumption. In the conventional PON-based mobile backhaul network, where base stations (BSs) are co-located with optical network units, the traffic between the neighboring BSs that are mainly caused by user mobility has to be first sent to the optical line terminal and even further, e.g., edge nodes of mobile core networks, resulting in high latency, although the adjacent BSs are geographically located close to each other. In this paper, a novel PON-based architecture is proposed for mobile backhaul to enhance the connectivity between neighboring BSs. Meanwhile, a tailored medium access control protocol and dynamic bandwidth allocation algorithm are introduced to support fast inter-BS communications. The results reveal that a low latency (less than 1 ms packet delay) for communications among any adjacent BSs can be achieved in the proposed PON-based mobile backhaul network, demonstrating great potential to support future time-critical applications.

    关键词: Low latency,Mobile backhaul,Passive optical network,User mobility,Inter-base station communications

    更新于2025-09-23 15:22:29

  • [IEEE 2018 International Power Electronics Conference (IPEC-Niigata 2018 –ECCE Asia) - Niigata, Japan (2018.5.20-2018.5.24)] 2018 International Power Electronics Conference (IPEC-Niigata 2018 -ECCE Asia) - Green Base Station Using Robust Solar System and High Performance Lithium ion battery for Next Generation Wireless Network (5G) and against Mega Disaster

    摘要: To secure wireless communication services, we are researching and developing disaster-resistant and environmentally friendly green base stations. One effective disaster countermeasure in carriers is to make backup time long for base stations during a power outage. Therefore, we have developed a photovoltaics (PV) system for green base stations to prolong the backup. In this paper, we propose a power control method that realizes long-term autonomous operation by PV and lithium-ion batteries (LiB) and regeneration operation by only PV for when commercial power is lost during a power outage and describe the results obtained at field test station.

    关键词: Lithium- ion battery,Green Base Station

    更新于2025-09-23 15:21:21

  • [IEEE 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Munich, Germany (2019.6.23-2019.6.27)] 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Atomic Vapor Confined in a Nanoscale Geometry: From Mesoscopic to Collective Effects

    摘要: Simulation data from a ray-tracing tool applied in specific urban environments in the 28-GHz band suggest that the utilization of arbitrary base station (BS) angles in a directional search procedure may not be of maximum benefit for users located in non-line-of-sight positions, because certain angles restrict the radio frequency illumination to a lower maximum power than from others. An appropriate selection of BS angles offers a potential power level benefit of greater than 2 dB in a defined number of consecutive measurements; however, this performance improvement appears to be conditioned by the severity of the existing street canyon propagation and the probability of the angle used. A simple ray tracing method is proposed to approximately identify the most effective BS angles that avoid power emissions in directions largely blocked by nearby buildings. The results indicate that prior site-specific information may be helpful, particularly for systems using analog beamforming.

    关键词: Angle of arrival,millimeter wave,user equipment,ray tracing,non-line-of-sight,base station,radio frequency,beam direction

    更新于2025-09-19 17:13:59

  • [IEEE 2019 Workshop on Recent Advances in Photonics (WRAP) - Guwahati, India (2019.12.13-2019.12.14)] 2019 Workshop on Recent Advances in Photonics (WRAP) - Photonic Crystal Fiber based Surface Plasmon Resonance Bio- Sensors with bimetallic selectively filled metal layers

    摘要: The performance of cellular system significantly depends on its network topology, while cellular networks are undergoing a heterogeneous evolution. This promising trend introduces the unplanned deployment of smaller base stations (BSs), thus complicating the performance evaluation even further. In this paper, based on large amount of real BS locations data, we present a comprehensive analysis on the spatial modeling of a cellular network structure. Unlike the related works, we divide the BSs into different subsets according to geographical factor (e.g., urban or rural) and functional type (e.g., macrocells or microcells), and perform a detailed spatial analysis to each subset. After discovering the inaccuracy of the Poisson point process in BS locations modeling, we consider the Gibbs point processes as well as Neyman–Scott point processes and compare their performance in the view of a large-scale modeling test, and finally reveal the general clustering nature of BSs deployment. This paper carries out the first large-scale identification regarding available literature, and provides more realistic and general results to contribute to the performance analysis for the forthcoming heterogeneous cellular networks.

    关键词: Cellular networks,base station (BS) locations,large-scale identification,Poisson point process,stochastic geometry

    更新于2025-09-19 17:13:59

  • [IEEE 2019 IEEE 8th International Conference on Advanced Optoelectronics and Lasers (CAOL) - Sozopol, Bulgaria (2019.9.6-2019.9.8)] 2019 IEEE 8th International Conference on Advanced Optoelectronics and Lasers (CAOL) - Generation of radially polarized beams by intracavity waveguide technique

    摘要: The development of base stations (BSs) with large aperture antenna arrays, enabled partially by the utilization of cmWave and mmWave frequency bands, will require radiated testing in fading conditions. In this paper, the objective is to investigate the suitable measurement distances and physical dimensions of the over-the-air setups for the performance evaluation of massive multiple-input multiple-output (MIMO) BSs in anechoic chambers with multiple probes. Setup dimension is the major cost factor in the test systems and is thus the key issue to be investigated. The purpose is to determine whether the conventional far field criteria must be followed when determining the range of the setup or if they can be relieved. The impact of limited test setup dimension on various metrics, e.g., far field criteria, field performance within the test area, system link budget analysis, direction of arrival estimation algorithm as well as multi-user MIMO sum-rate capacity are investigated to determine the range of the test setup. It was found that the link budget does not support for the measurement distances claimed by the Fraunhofer distance. Most of the utilized metrics, especially the sum rate capacity, indicate that smaller setup sizes can still yield reasonable measurement accuracy. Simulations were performed at 2.6, 3.5, and 28 GHz frequencies.

    关键词: over the air testing,performance evaluation,Massive MIMO base station,multi-probe anechoic chamber setup.

    更新于2025-09-19 17:13:59

  • [IEEE 2019 IEEE 2nd International Conference on Renewable Energy and Power Engineering (REPE) - Toronto, ON, Canada (2019.11.2-2019.11.4)] 2019 IEEE 2nd International Conference on Renewable Energy and Power Engineering (REPE) - Perovskite solar cells-A futuristic approach

    摘要: Simulation data from a ray-tracing tool applied in specific urban environments in the 28-GHz band suggest that the utilization of arbitrary base station (BS) angles in a directional search procedure may not be of maximum benefit for users located in non-line-of-sight positions, because certain angles restrict the radio frequency illumination to a lower maximum power than from others. An appropriate selection of BS angles offers a potential power level benefit of greater than 2 dB in a defined number of consecutive measurements; however, this performance improvement appears to be conditioned by the severity of the existing street canyon propagation and the probability of the angle used. A simple ray tracing method is proposed to approximately identify the most effective BS angles that avoid power emissions in directions largely blocked by nearby buildings. The results indicate that prior site-specific information may be helpful, particularly for systems using analog beamforming.

    关键词: Angle of arrival,millimeter wave,user equipment,ray tracing,non-line-of-sight,base station,radio frequency,beam direction

    更新于2025-09-19 17:13:59

  • [IEEE 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Chicago, IL, USA (2019.6.16-2019.6.21)] 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Rear Heterojunction GaAs Solar Cells With Strain-Balanced GaInAs/GaAsP Quantum Wells

    摘要: Simulation data from a ray-tracing tool applied in specific urban environments in the 28-GHz band suggest that the utilization of arbitrary base station (BS) angles in a directional search procedure may not be of maximum benefit for users located in non-line-of-sight positions, because certain angles restrict the radio frequency illumination to a lower maximum power than from others. An appropriate selection of BS angles offers a potential power level benefit of greater than 2 dB in a defined number of consecutive measurements; however, this performance improvement appears to be conditioned by the severity of the existing street canyon propagation and the probability of the angle used. A simple ray tracing method is proposed to approximately identify the most effective BS angles that avoid power emissions in directions largely blocked by nearby buildings. The results indicate that prior site-specific information may be helpful, particularly for systems using analog beamforming.

    关键词: Angle of arrival,user equipment,radio frequency,non-line-of-sight,beam direction,base station,millimeter wave,ray tracing

    更新于2025-09-19 17:13:59

  • [IEEE 2019 Electric Power Quality and Supply Reliability Conference (PQ) & 2019 Symposium on Electrical Engineering and Mechatronics (SEEM) - K?¤rdla, Estonia (2019.6.12-2019.6.15)] 2019 Electric Power Quality and Supply Reliability Conference (PQ) & 2019 Symposium on Electrical Engineering and Mechatronics (SEEM) - Analysis of Harmonic Current Stability and Summation of LED Lamps

    摘要: In this paper, radio-frequency (RF) electromagnetic field (EMF) exposure evaluations are conducted in the frequency range 10–60 GHz for array antennas intended for user equipment (UE) and low-power radio base stations in 5G mobile communication systems. A systematic study based on numerical power density simulations considering effects of frequency, array size, array topology, distance to exposed part of human body, and beam steering range is presented whereby the maximum transmitted power to comply with RF EMF exposure limits specified by the International Commission on Non-Ionizing Radiation Protection, the US Federal Communications Commission, and the Institute of Electrical and Electronics Engineers is determined. The maximum transmitted power is related to the maximum equivalent isotropically radiated power to highlight the relevance of the output power restrictions for a communication channel. A comparison between the simulation and measurement data is provided for a canonical monopole antenna. For small distances, with the antennas transmitting directly toward the human body, it is found that the maximum transmitted power is significantly below the UE power levels used in existing third and fourth generation mobile communication systems. Results for other conceivable exposure scenarios based on technical solutions that could allow for larger output power levels are also discussed. The obtained results constitute valuable information for the design of future mobile communication systems and for the standardization of EMF compliance assessment procedures of 5G devices and equipment.

    关键词: mobile user equipment,5G mobile communication,RF EMF exposure,beam steering,radio base station,mobile device,antenna arrays

    更新于2025-09-19 17:13:59

  • [IEEE 2019 XIth International Scientific and Practical Conference on Electronics and Information Technologies (ELIT) - Lviv, Ukraine (2019.9.16-2019.9.18)] 2019 XIth International Scientific and Practical Conference on Electronics and Information Technologies (ELIT) - Computational-Measurement System a??Nanoplasmonicsa??. Part 2: Structure of Microservices

    摘要: Ray tracing simulation results indicate that a high-resolution database is not needed to exploit user position knowledge in the 28-GHz band, even in the case of inexact information. A proposed antenna alignment algorithm (using maximum position errors and database resolutions of 10 and 4 m, respectively) that takes advantage of the propagation characteristics knowledge of database points located around the reported location is applied. The results show that the distance between the points can be increased up to 2 m with no considerable negative impact on performance. Simulations also indicate that this outcome is sustained when the maximum power level received at the user equipment varies. The algorithm provides the benefit of a higher initial power delivery and fewer steps, as long as the exact geographical position of the user is within the circular area containing the considered database points. The performance is similar to or better than that of a modified classical hierarchical procedure.

    关键词: Base station (BS),database (DB),non-line of sight (NLOS),millimeter wave (mmW),ray tracing (RT),user equipment (UE),signal-to-noise ratio (SNR)

    更新于2025-09-16 10:30:52