- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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Underwater optical wireless sensor networks using resource allocation
摘要： Optical wireless communications is an energy efficient and cost-effective solution for high speed and high secure wireless connections. In this paper, we propose an underwater optical wireless sensor network using multiple input multiple output technique and power allocation algorithm for supporting multiple users with the impacts of underwater channel uncertainty interferences. In proposed power allocation algorithm, all the LED nodes in are coordinated and controlled by a central controller; each LED node supports all the users within its field of view. To separate users, optical code division multiple access is used; cyclic optical orthogonal code working as CDMA code is employed. At the receiver, a minimal mean squared error (MMSE) filter is uniquely designed for each user. The MMSE filters and the assigned power can be jointly optimized to improve the overall throughput and signal to noise ratio. Since the system performance may be impacted by the underwater channel uncertainty, the proposed power allocation can use the predicted channel uncertainty variance to reduce the interference of the channel uncertainty and improve the signal to noise ratio. Compared to the equal power allocation algorithm, the proposed algorithm can support longer transmission distance, higher bit rate and lower bit error rate.
关键词： Multiple access interference,Underwater communications,Wireless sensor networks,Channel uncertainty,MIMO system,CDMA,Optical wireless communications,Resource allocation
更新于2025-09-23 15:23:52
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Adaptive resource allocation in FSO/RF multiuser system with proportional fairness for UAV application
摘要： The combination of free space optic(FSO) and unmanned aerial vehicle (UAV) can be a promising solution to last-mile problem because of FSO high bandwidth and flexibility of UAV. However, FSO is vulnerable to the atmospheric turbulence and transmitter configuration is limited on UAV. Therefore, in this paper, we investigate an adaptive resource allocation strategy to provide relative fair and high transmission capacity for users. In the proposed network model, the downlink scenario is considered and ground station communicates with UAV and its local users by FSO and RF links, respectively. According to the channel conditions and rate requirements from users, channel and power assignments should satisfy the capacity demand in reasonable. To this end, we decompose the original channel and power allocation problem with high computational complexity into low-complexity subproblems, corresponding to channel allocation in RF transmission phase and channel matching and power allocation in FSO transmission phase. Then, a heuristic efficient resource assignment algorithm is proposed to achieve the optimal capacity distribution for users. Numerical results show that the proposed method can asymptotically achieve optimal throughput. Furthermore, system throughput is higher at low transmitting power requirement than those of other existing methods.
关键词： UAV,proportional fairness,mixed FSO/RF,efficient resource allocation,channel capacity
更新于2025-09-23 15:23:52
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Joint Optimal Transceiver Placement and Resource Allocation Schemes for Redirected Cooperative Hybrid FSO/mmW 5G Fronthaul Networks
摘要： To meet the requirements of the 5G mobile network, a new innovative approach called centralized radio access network (C-RAN) architecture is introduced. In C-RAN architecture, the fronthaul network must provide high capacity, high availability, and low latency to be able to transmit massive traffic between remote radio heads (RRHs) and baseband processing units. In this paper, two joint transceiver placement and resource allocation schemes are proposed for redirected cooperative hybrid free-space optics (FSO)/millimeter-wave (mmW) fronthaul networks. The schemes aim to obtain the optimal FSO/mmW transceiver placement that optimizes reliability, average transmitted power, average bit error rate (BER), and number of disrupted links of redirected cooperative hybrid FSO/mmW fronthaul networks in various weather conditions. The schemes are formulated as multiobjective and bilevel integer linear programming problems and solved by using an exhaustive search method to obtain optimal solutions. The numerical results reveal that improvements are obtained in the network reliability, average transmitted power, and average BER by implementing the optimal placement, especially at low visibility and/or high rainfall rate conditions.
关键词： C-RAN,FSO,5G,mmW,Optimal transceiver placement,RRH,Resource allocation,BBU
更新于2025-09-23 15:22:29
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Three-Dimensional Resource Allocation in Space Division Multiplexing Elastic Optical Networks
摘要： In this paper, we present a comprehensive model to address three-dimensional resource assignment (3D-RA) in space division multiplexing elastic optical networks using few-mode multi-core fibers (FM-MCFs). Accordingly, we present new 3D-RA algorithms in which the consequential resources include the spectrum, modes, and cores. We consider all spectral and spatial diversity types in FM-MCFs and introduce five 3D-RA scenarios including (i) single-mode and single-core (SMSC), (ii) single-mode and multi-core (SMMC), (iii) multi-mode and single-core (MMSC), (iv) multi-mode and multi-core (MMMC), and finally, (v) hybrid 3D-RA. In each scenario, the fractional joint (FrJ-) and independent (Ind-) switching (Sw) schemes are introduced and explored for the proposed scenarios. By using the FrJ- and Ind-Sw schemes, we performed the simulation process for the above-mentioned scenarios. The simulation results confirm the efficiency of the proposed 3D-RA algorithms. Furthermore, various 3D-RA scenarios are comprehensively compared using the obtained results in terms of vital metrics introduced in this work. It is also indicated that the SMSC and MMSC scenarios present superior performance for Ind-Sw and FrJ-Sw 3D-RA scenarios, respectively, in comparison to other proposed non-hybrid scenarios. The obtained results also reveal that the quad-hybrid 3D-RA scenario results in the lowest blocking probability in comparison with all other introduced scenarios in both switching schemes. These results recommend an efficient simulation system for compatible transceivers for Ind- and FrJ-Sw schemes.
关键词： Spectral and spatial resource allocation,Few mode-multi core fiber,Space division multiplexing,Elastic optical network
更新于2025-09-23 15:22:29
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Cluster-based Resource Allocation and User Association in mmWave Femtocell Networks
摘要： In millimeter wave(mmW) dense femto-networks, major challenges are overcoming the performance loss imposed by channel and managing the co-channel interference. The former is due to mmW susceptibility to pathloss and shadowing and the latter is due to density of the network. We cope with both challenges by a clustering method designed for mmW environment. In our approach, the femto access points (FAP) and femto users (FU) are clustered based on having the most line of sight connectivity. We modify this binary optimization problem into a continuous problem using deductive penalty functions and solve it by difference of two convex functions (D.C.) programming. Our clustering algorithm achieves higher data rate compared to the foremost clustering method. We also propose a technique to assign FUs to FAPs in each cluster which has near-optimal performance and polynomial time complexity. We solve mixed integer nonlinear programming of power and sub-channel allocation by D.C. programming. Instead of using the deductive penalty terms in D.C. programming, we penalize the objective function in a multiplicative manner. Thus, the penalty term depends on both constraint violation and objective function. Our scheme achieves around 10% higher data rate compared to the method using deductive penalty terms.
关键词： D.C. programming,Resource allocation,Multiplicative penalty function,User association,Clustering,mmWave,Femto cell
更新于2025-09-23 15:21:21
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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) - Impact of Dynamic Shading in cSi PV Modules and Systems for Novel Applications
摘要： With the dense deployment of small cells in the next generation of mobile networks, the users from different tiers suffer from high downlink interferences. In this paper, we propose a game theoretic approach for joint co-tier and cross-tier collaboration in heterogeneous networks and analyze the relevance of the proposed scheme. First, we propose a coalition structure game with a weighted Owen value as imputation, where the small-cell base stations (SBSs) and their connecting macrocell user equipments (MUEs) form a priori union. We prove that the proposed framework optimizes the users profit. As an additional global benefit, the SBSs are encouraged to host the harmed public users in their vicinity. Second, we propose a canonical game with a weighted solidarity value as imputation to allow cooperation among SBSs and MUEs when they fail to connect to nearby SBSs. We prove that the weak players are protected in this scheme and that a high degree of fairness is provided in the game. We compare through extensive simulations the proposed frameworks with state-of-the-art resource allocation solutions, access modes, and legacy game-theoretic approaches. We show that the proposed framework obtains the best performances for the MUEs and small-cells user equipments in terms of throughput and fairness. Throughput gain is in order of 40% even reaching 50% for both types of users.
关键词： game theory,interference mitigation,resource allocation,heterogeneous networks,cooperative games,Small-cells
更新于2025-09-23 15:21:01
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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) - Solder Bond Degradation of Fielded PV Modules: Climate Dependence of Intermetallic Compound Growth
摘要： Energy-ef?cient resource allocation is investigated for multi-pair massive MIMO amplify-and-forward relay systems, where a dedicated relay assists pairwise information exchange among many pieces of single-antenna user equipment (UE). The system energy ef?ciency (EE) is theoretically analyzed by employing large system analysis and random matrix theory. This analytical result provides excellent approximation for the system with a moderate number of antennas, and it also enables several ef?cient algorithms, working with a different knowledge of channel state information (CSI), to maximize the system EE by scheduling the optimal numbers of relay antennas and UE pairs as well as the corresponding relay transmission power. In contrast to the conventional resource allocation schemes, the proposed algorithms avoid complicated matrix calculations and the instantaneous CSI of small-scale fading; therefore, they are computationally ef?cient with low CSI overhead. The proposed optimization framework sheds light on the optimized system con?gurations, and it also offers an ef?cient way to achieve EE-oriented resource allocation for the multi-pair massive MIMO relay systems.
关键词： Energy-ef?cient,resource allocation,low-complexity,massive MIMO relay
更新于2025-09-23 15:21:01
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Resource and Power Allocation in SWIPT Enabled Device-to-Device Communications Based on a Non-Linear Energy Harvesting Model
摘要： Due to the limited battery capacity in mobile devices, simultaneous wireless information and power transfer (SWIPT) has been proposed as a promising solution to improving the energy efficiency (EE) in Internet of things (IoT) networks, i.e., device-to-device (D2D) networks, by allowing mobile devices to harvest energy from ambient radio frequency (RF) signals. However, the non-linear behavior of RF energy harvesters has largely been ignored in existing works on SWIPT. In this paper, we propose to maximize the sum EE of all D2D links in a D2D underlaid cellular network by optimizing the resource and power allocation based on a non-linear energy harvesting (EH) model. Toward this end, we first propose a pre-matching algorithm to divide the D2D links into a SWIPT enabled group and a non-EH group that cannot meet the EH circuit sensitivity. We then develop a two-layer iterative algorithm to jointly optimize the D2D transmission power and the power splitting ratio to maximize the EE for each SWIPT enabled D2D link. On this basis, we build the preference lists for both SWIPT enabled D2D links and cellular user equipment (CUEs), and propose a one-to-one constraint stable matching algorithm to maximize the sum EE of all SWIPT enabled D2D links by optimizing the spectrum resource sharing between D2D links and CUEs. The sum EE of non-EH D2D links is maximized through an iterative power control algorithm and a one-to-one stable matching algorithm. Simulation results show that our proposed algorithms achieve a much higher sum EE than the existing matching based energy-efficient resource allocation scheme for SWIPT enabled D2D networks.
关键词： Device-to-device,underlay,energy harvesting,power control,resource allocation,SWIPT,energy efficiency,matching theory
更新于2025-09-23 15:21:01
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[IEEE 2019 3rd International Symposium on Multidisciplinary Studies and Innovative Technologies (ISMSIT) - Ankara, Turkey (2019.10.11-2019.10.13)] 2019 3rd International Symposium on Multidisciplinary Studies and Innovative Technologies (ISMSIT) - Concentrated Photovoltaic Solar Power Investigation in Space Application
摘要： In this paper, we consider a network in which lower power nodes (LPNs) are deployed jointly within macrocells. However, there are significant differences between the transmit power levels, coverage areas, and deployment densities of these two types of base stations. Such disparities lead to an unfair load distribution, as well as a lower throughput for picocells’users equipments (UEs). A good solution to such issues is the exploitation of the cell range expansion (CRE) technique. Although CRE has widely proven its effectiveness, it may degrade the network capacity if the cell bias is not chosen properly. In fact, it may generate severe intercell interference at extended region cell (ERC) UEs, which leads to a deterioration of their throughput. We thus propose a downlink coordinated cell range expansion for mobility management (CCREMM) strategy that analytically computes the joint optimal bias at picocells and macrocells. CCREMM mitigates the interference at ERC-UEs by accounting for their maximum tolerable interference. Moreover, CCREMM reaches the load balancing and the UE QoS satisfaction by accounting for additional parameters. It will be proven that our strategy which is associated with the maximum throughput scheduling technique, results in a cell load-balancing improvement, fairness, and a 50–90% UE throughput enhancement. These performance figures are shown to surpass those achieved by alternative approaches proposed in the existing literature.
关键词： HetNets,load balancing,QoS,resource allocation,mobility management
更新于2025-09-23 15:19:57
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An Experimental Study on Mixed-dimensional 1D-2D van der Waals Single-Walled Carbon Nanotube-WSe2 Hetero-Junction
摘要： Parking in major cities, particularly with dense traffic, directly effects the traffic flow and people’s life. In this paper, we introduce a new smart parking system that is based on intelligent resource allocation, reservation, and pricing. The proposed system solves the current parking problems by offering guaranteed parking reservations with the lowest possible cost and searching time for drivers and the highest revenue and resource utilization for parking managers. New fair pricing policies are also proposed that can be implemented in practice. The new system is based on mathematical modeling using mixed-integer linear programming (MILP) with the objective of minimizing the total monetary cost for the drivers and maximizing the utilization of parking resources.
关键词： dynamic resource allocation,smart car parking,mixed integer linear programming (MILP),reservation,Dynamic pricing
更新于2025-09-23 15:19:57