- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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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) - SUPER PV project a?? Developing innovative PV systems for cost reduction and enhanced performance
摘要： Performance of cellular communication systems is typically enhanced by leveraging the three dimensions of system transmission bandwidth, area frequency reuse, i.e. system access point (AP) density, and spectral ef?ciency of employed radio air interface, referred to as the radio access technology (RAT). In particular, re?ned RATs are continuously introduced to compensate for limited spectrum availability and restrictions on system AP densi?cation in cellular communication systems. While the performance of cellular communication systems is maximized by employing a single RAT providing maximal spectral ef?ciency, varying capabilities of user equipment compels the co-deployment of multiple RATs in cellular communication systems and entails fragmenting system radiofrequency resources between co-deployed RATs. Nevertheless, the inef?cient structuring of multi-RAT systems as independently operated collocated single-RAT subsystems results in unbalanced system loading, suboptimal spectrum utilization, and the omission of multiuser diversity as a performance enhancement dimension in multi-RAT systems. The omitted dimension of multiuser diversity is exploited in this paper, through multiple means and techniques, to further enhance the performance of multi-RAT data cellular communication systems. Unifying the architectural structure of multi-RAT systems is proposed to eliminate the redundant duplication of radio access network functions and elements, reduce system deployment costs and operational complexity, improve system scalability, and enable the joint execution of non-radio transmission functions for all co-deployed RATs. By fully exploiting system multiuser diversity, the joint allocation of system radiofrequency resources under autonomous spectrum assignment is shown to substantially enhance the performance of all employed RATs, in addition to the overall performance of multi-RAT systems, without extending any of the three typical performance enhancement dimensions of cellular communication systems.
关键词： user access,radio resource allocation,multi-radio access technology systems,user equipment,spectrum management,radio access networks,Cellular communication systems,radio access technologies
更新于2025-09-19 17:13:59
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[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
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[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
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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) - 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
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[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
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[IEEE 2019 Photonics North (PN) - Quebec City, QC, Canada (2019.5.21-2019.5.23)] 2019 Photonics North (PN) - Laser ablation generation of gold nanoparticles for highly efficient optical humidity sensor
摘要： Performance of cellular communication systems is typically enhanced by leveraging the three dimensions of system transmission bandwidth, area frequency reuse, i.e. system access point (AP) density, and spectral ef?ciency of employed radio air interface, referred to as the radio access technology (RAT). In particular, re?ned RATs are continuously introduced to compensate for limited spectrum availability and restrictions on system AP densi?cation in cellular communication systems. While the performance of cellular communication systems is maximized by employing a single RAT providing maximal spectral ef?ciency, varying capabilities of user equipment compels the co-deployment of multiple RATs in cellular communication systems and entails fragmenting system radiofrequency resources between co-deployed RATs. Nevertheless, the inef?cient structuring of multi-RAT systems as independently operated collocated single-RAT subsystems results in unbalanced system loading, suboptimal spectrum utilization, and the omission of multiuser diversity as a performance enhancement dimension in multi-RAT systems. The omitted dimension of multiuser diversity is exploited in this paper, through multiple means and techniques, to further enhance the performance of multi-RAT data cellular communication systems. Unifying the architectural structure of multi-RAT systems is proposed to eliminate the redundant duplication of radio access network functions and elements, reduce system deployment costs and operational complexity, improve system scalability, and enable the joint execution of non-radio transmission functions for all co-deployed RATs. By fully exploiting system multiuser diversity, the joint allocation of system radiofrequency resources under autonomous spectrum assignment is shown to substantially enhance the performance of all employed RATs, in addition to the overall performance of multi-RAT systems, without extending any of the three typical performance enhancement dimensions of cellular communication systems.
关键词： spectrum management,radio access technologies,radio access networks,user equipment,Cellular communication systems,multi-radio access technology systems,user access,radio resource allocation
更新于2025-09-16 10:30:52
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[IEEE 2019 International Conference on Numerical Simulation of Optoelectronic Devices (NUSOD) - Ottawa, ON, Canada (2019.7.8-2019.7.12)] 2019 International Conference on Numerical Simulation of Optoelectronic Devices (NUSOD) - Numerical Designing of Optical Waveguide by Curvilinear Coordinates
摘要： Performance of cellular communication systems is typically enhanced by leveraging the three dimensions of system transmission bandwidth, area frequency reuse, i.e. system access point (AP) density, and spectral efficiency of employed radio air interface, referred to as the radio access technology (RAT). In particular, refined RATs are continuously introduced to compensate for limited spectrum availability and restrictions on system AP densification in cellular communication systems. While the performance of cellular communication systems is maximized by employing a single RAT providing maximal spectral efficiency, varying capabilities of user equipment compels the co-deployment of multiple RATs in cellular communication systems and entails fragmenting system radiofrequency resources between co-deployed RATs. Nevertheless, the inefficient structuring of multi-RAT systems as independently operated collocated single-RAT subsystems results in unbalanced system loading, suboptimal spectrum utilization, and the omission of multiuser diversity as a performance enhancement dimension in multi-RAT systems. The omitted dimension of multiuser diversity is exploited in this paper, through multiple means and techniques, to further enhance the performance of multi-RAT data cellular communication systems. Unifying the architectural structure of multi-RAT systems is proposed to eliminate the redundant duplication of radio access network functions and elements, reduce system deployment costs and operational complexity, improve system scalability, and enable the joint execution of non-radio transmission functions for all co-deployed RATs. By fully exploiting system multiuser diversity, the joint allocation of system radiofrequency resources under autonomous spectrum assignment is shown to substantially enhance the performance of all employed RATs, in addition to the overall performance of multi-RAT systems, without extending any of the three typical performance enhancement dimensions of cellular communication systems.
关键词： user access,radio resource allocation,multi-radio access technology systems,user equipment,spectrum management,radio access networks,Cellular communication systems,radio access technologies
更新于2025-09-16 10:30:52
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[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
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Spatio-Temporal Impact of Hand and Body Blockage for Millimeter-Wave User Equipment Design at 28 GHz
摘要： The recently proposed channel model by the Third Generation Partnership Project for fifth generation New Radio (5G-NR) systems at millimeter-wave carrier frequencies in TR38.901 provides a good starting point for understanding the impact of propagation, material penetration, and blockage in cellular access systems. With this backdrop, the focus of this article is on hand and body blockage which have a significant bearing on user equipment (UE) design and in the practical viability of millimeter-wave systems. Building on TR38.901, we first study hand and body blockage loss with experiments using a 28 GHz experimental prototype that emulates a 5G base station and a form-factor UE. These measurement estimates show that while blockage losses can be substantial, they are significantly lower than the agreed model in TR38.901. We then study the implications of these revised estimates on spherical coverage with the UE. For this, we consider two form-factor UE designs: a face design and an edge design. Our studies show that while both designs are generally comparable in terms of spherical coverage, practical design considerations favor the edge design over the face design. We finally report on the timescales at which blockage events occur and show that given the symbol periods in 5G-NR, it is possible to implement mitigation strategies to overcome blockage (e.g., switch beams at the UE from a blocked path to an unblocked path).
关键词： body blockage,hand blockage,user equipment design,beam switching,spherical coverage,millimeter-wave,5G
更新于2025-09-09 09:28:46
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[Institution of Engineering and Technology 12th European Conference on Antennas and Propagation (EuCAP 2018) - London, UK (9-13 April 2018)] 12th European Conference on Antennas and Propagation (EuCAP 2018) - Effective beam-scanning efficiency of millimeter-wave subarrays for 5G user equipment application
摘要： The forthcoming 5G communication system is expected to adopt millimeter-wave bands in order to satisfy the ever-growing traffic explosion. The coverage efficiency was proposed in earlier works to evaluate the beam-scanning capability and coverage performance of array antennas implemented in 5G user equipment. However, when multi-subarray configurations are introduced into user equipment, the coverage efficiency fails to reflect the coverage performance of each subarray under the influence of housing. In this paper, we use the effective beam-scanning efficiency to evaluate the coverage performance of a subarray covered by a superstrate. The results provide valuable insight into 5G mobile antenna design.
关键词： 5G,effective beam-scanning efficiency,user equipment,millimeter-wave array antenna,coverage efficiency,subarray
更新于2025-09-04 15:30:14