- 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 3rd International Conference on Recent Developments in Control, Automation & Power Engineering (RDCAPE) - NOIDA, India (2019.10.10-2019.10.11)] 2019 3rd International Conference on Recent Developments in Control, Automation & Power Engineering (RDCAPE) - Impact of Solar Photovoltaic Penetration In Distribution Network
摘要： In this paper, we consider the down-link dynamic resource allocation in multi-cell virtualized wireless networks (VWNs) to support the users of different service providers (slices) within a specific region by a set of base stations (BSs) through orthogonal frequency division multiple access (OFDMA). In particular, we develop a joint BS assignment, sub-carrier, and power allocation algorithm to maximize the network sum rate, while satisfying the minimum required rate of each slice. Under the assumption that each user at each transmission instance can connect to no more than one BS, we introduce the user-association factor to represent the joint sub-carrier and BS assignment as the optimization variable vector in the problem formulation. Sub-carrier reuse is allowed in different cells, but not within one cell. As the proposed optimization problem is inherently non-convex and NP-hard, by applying the successive convex approximation (SCA) and complementary geometric programming (CGP), we develop an efficient two-step iterative approach with low computational complexity to solve the proposed problem. For a given problem, Step 1 derives the optimum user-association and subsequently, and for an obtained user-association, Step 2 finds the optimum power allocation. Simulation results demonstrate that the proposed iterative algorithm outperforms the traditional approach in which each user is assigned to the BS with the largest average value of signal strength, and then, joint sub-carrier and power allocation is obtained for the assigned users of each cell. Simulation results reveal a coverage improvement, offered by the proposed approach, of 57% and 71% for uniform and non-uniform users distribution, respectively, leading to higher spectrum efficiency for VWN.
关键词： joint user association and resource allocation,successive convex approximation,virtualized wireless networks,Complementary geometric programming
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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Depth Camera Using High-Transmittance Off-Axis Dual Electro-Optical Irises
摘要： This paper investigates the resource allocation problem in device-to-device (D2D) communications underlaying a non-orthogonal multiple access (NOMA)-based cellular network with energy harvesting, where the energy harvesting-powered D2D communications share the downlink resources of the cellular network. To fully exploit the high-data-rate D2D links in this system, a two-phase framework is proposed for D2D users. In particular, the D2D users harvest energy from the base station (BS) in the first phase and then transmit their own information using the harvested energy in the second one. Meanwhile, the D2D communications could cause severe interference to cellular users (CUs) and hence probably ruin the SIC decoding order of the CUs. To deal with this issue, joint power allocation and time scheduling scheme is proposed to maximize the throughput of the D2D links while guaranteeing the quality of service (QoS) for each CU. Through rigorous derivation, the optimal power control and time scheduling parameters are analyzed to simplify the optimization problem formulation. The closed-form optimal solution is derived in some cases. In other cases, a gradient-based algorithm is employed to find an appropriate sub-optimal solution. The simulation results are demonstrated to validate the superiority of the proposed scheme over the conventional orthogonal multiple access (OMA) scheme.
关键词： energy harvesting,NOMA,D2D,resource allocation,cellular networks
更新于2025-09-11 14:15:04
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[IEEE 2018 International Conference on Smart Computing and Electronic Enterprise (ICSCEE) - Shah Alam, Malaysia (2018.7.11-2018.7.12)] 2018 International Conference on Smart Computing and Electronic Enterprise (ICSCEE) - Energy Harvesting For Efficient 5G Networks
摘要： The design of traditional mobile wireless network emphasises on large capacity as well as ubiquitous access. However, environmental protection and energy saving may soon become inevitable trends due to rising global demands. In the wireless networking field, researchers should shift their focus towards efficient networks and energy harvesting (EH). In this work, we consider energy efficiency and EH to address the issue of energy shortage, which also represents the ratio of the quantity of data that have been transferred to the dissipated energy within the system, simultaneously. The simulation-based mathematics signifies the relation between energy efficiency ((cid:2159)(cid:2161)(cid:4667) against the training interval ((cid:2176)(cid:2202)(cid:4667) and how the energy efficiency is impacted by the change in block size and number of users.
关键词： 5G,Wireless Communication,Resource Allocation,Energy Harvesting(EH),Information Decoding(ID),Green Transmission,Networking
更新于2025-09-10 09:29:36
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Downlink resource allocation for dynamic TDMA-based VLC systems
摘要： Visible light communications (VLC) in general and resource allocation for VLC networks particularly have gained lots of attention recently. In this work, we consider the resource allocation problem of a VLC downlink transmission system employing dynamic time division multiple access where time and power variables are tuned to maximize spectral ef?ciency (SE). As for the operational conditions, we impose constraints on the average optical intensity, the energy budget and the quality-of-service. To solve the non-convex problem, we transform the objective function into a difference of concave functions by solving a second order differential inequality. Then, we propose a low-complexity algorithm to solve the resource allocation problem. Finally, we show by simulations the SE performance gains achieved by optimizing time and power allocation over the initial total power minimization solution for the considered system.
关键词： spectral ef?ciency,resource allocation,DC programming,illumination constraint,Visible light communication
更新于2025-09-09 09:28:46
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Multiple Access Design for Ultra-Dense VLC Networks: Orthogonal v.s. Non-Orthogonal
摘要： Small cell aided ultra-dense networks (UDN) constitute an efficient solution to the ever-increasing thirst for more data. Thanks to the vast untapped high-frequency spectrum of visible light, visible light communications (VLC) is a natural candidate for UDN. In this paper, layered asymmetrically clipped optical OFDM (LACO-OFDM) aided ultra-dense VLC (UD-VLC) is investigated in terms of its user-association, multiple access (MA) and resource allocation. To handle the severe inter-cell interference (ICI) amongst the densely-deployed access points (AP), we propose a novel overlapped clustering technique relying on a hybrid non-orthogonal MA (NOMA) and orthogonal MA (OMA) scheme for enhancing the performance, with the aid of our dynamic resource allocation conceived. Our simulations show that the proposed LACO-OFDM aided UD-VLC using our hybrid MA scheme is more robust against the ICI, at a price of modestly decreasing the sum-throughput.
关键词： visible light communications (VLC),resource allocation,non-orthogonal multiple access (NOMA),Ultra-dense network (UDN),multiple access (MA)
更新于2025-09-09 09:28:46
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Optimal Resource Allocation Policies for Multi-User Backscatter Communication Systems
摘要： This paper considers a backscatter communication (BackCom) system including a reader and N tags, where each tag receives excitation signals transmitted by the reader and concurrently backscatters information to the reader in time-division-multiple-access (TDMA) mode. In this system, we aim to maximize the total system goodput by jointly optimizing reader transmission power, time allocation, and re?ection ratio for the cases of passive and semi-passive tags. For each case, an optimization problem is formulated, which is non-convex and can be solved by being decomposed into at most N feasible sub-problems based on the priority of allocated reader transmission power. First, for the passive tags case, by solving the convex sub-problems sequentially and comparing their maximum total goodput, we derive the optimal resource allocation policy. Then, for the semi-passive tags case, we ?nd a close-to-optimal solution, since each sub-problem can be reformulated as a biconvex problem, which is solved by a proposed block coordinate descent (BCD)-based optimization algorithm. Finally, simulation results demonstrate the superiority of the proposed resource allocation policies.
关键词： backscatter communication,total goodput maximization,resource allocation
更新于2025-09-04 15:30:14