- 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) - Quantum-Dot Intermediate-band Solar Cell used as Bottom Cell
摘要： Multiple transmitting antennas can considerably increase the downlink spectral efficiency by beamforming to multiple users at the same time. However, multiuser beamforming requires channel state information (CSI) at the transmitter, which leads to training overhead and reduces overall achievable spectral efficiency. In this paper, we propose and analyze a sequential beamforming strategy that utilizes full-duplex base station to implement downlink data transmission concurrently with CSI acquisition via in-band closed or open loop training. Our results demonstrate that full-duplex capability can improve the spectral efficiency of uni-directional traffic, by leveraging it to reduce the control overhead of CSI estimation. In moderate SNR regimes, we analytically derive tight approximations for the optimal training duration and characterize the associated respective spectral efficiency. We further characterize the enhanced multiplexing gain performance in the high SNR regime. In both regimes, the performance of the proposed full-duplex strategy is compared with the half-duplex counterpart to quantify spectral efficiency improvement. With experimental data and 3-D channel model from 3GPP, in a 1.4 MHz 8 × 8 system LTE system with the block length of 500 symbols, the proposed strategy attains a spectral efficiency improvement of 130% and 8% with closed and open loop training, respectively.
关键词： limited feedback,massive MIMO systems,multiuser MIMO systems,Wireless communication,full-duplex systems
更新于2025-09-16 10:30:52
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[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) - Luminescence of Polyamide-6 ?± and ?3 forms (Invited)
摘要： This paper focuses on energy efficiency aspects and related benefits of radio-access-network-as-a-service (RANaaS) implementation (using commodity hardware) as architectural evolution of LTE-advanced networks toward 5G infrastructure. RANaaS is a novel concept introduced recently, which enables the partial centralization of RAN functionalities depending on the actual needs as well as on network characteristics. In the view of future definition of 5G systems, this cloud-based design is an important solution in terms of efficient usage of network resources. The aim of this paper is to give a vision of the advantages of the RANaaS, to present its benefits in terms of energy efficiency and to propose a consistent system-level power model as a reference for assessing innovative functionalities toward 5G systems. The incremental benefits through the years are also discussed in perspective, by considering technological evolution of IT platforms and the increasing matching between their capabilities and the need for progressive virtualization of RAN functionalities. The description is complemented by an exemplary evaluation in terms of energy efficiency, analyzing the achievable gains associated with the RANaaS paradigm.
关键词： 5G,LTE-advanced,RAN-as-a-service,Energy efficiency,power model,radio access networks,cloud-RAN,wireless communication
更新于2025-09-16 10:30:52
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[IEEE 2019 6th International Conference on Space Science and Communication (IconSpace) - Johor Bahru, Malaysia (2019.7.28-2019.7.30)] 2019 6th International Conference on Space Science and Communication (IconSpace) - Koch Fractal Loop Circular Polarization (CP) Antenna Integrated with Solar Cells
摘要： Minimal profile antennas for wireless devices which characteristics consisted of being low cost, highly reliable, and lightweight, it bears a new challenge for the design of the antenna in wireless communications. In this paper, we propose a design of circularly polarized microstrip patch antenna integration with solar cells for green wireless applications. Two techniques have been proposed to form the prototype between the communication system (design of antenna) and solar panel (solar cell). Both methods will face two issues generally; the solar system needs to get 100% sunlight and the magnetic field produced by radio communication systems as well as the electric field produced by solar cells should not affect the efficiency. The antenna is composed of a Koch fractal loop patch and the substrate is employed using a transparent material. This enables the light to pass through with high efficiency to illuminate the solar panel cells while the RF performance is maintained with minimal degradation. The communication frequency measures 2.6, 3.5 and 4.4 GHz. CST MWS simulation is also studied and compared among the different substrates which show different results based on the same parameters, which is implemented with a lattice of 2×2 square solar cells. With this arrangement, the solar cells will be able to obtain 100% of sunlight exposure. The characteristics of the broadband are achieved by combining resonances and the minimum axial ratio points created by the driven patch and solar cell surface.
关键词： Trade-off RF transparency,Wireless communication,transparent substrate,Microstrip patch antenna,Compact Meshed patch antenna,integration antenna and solar panel,CST MWS,performances and Frequency,Gain
更新于2025-09-12 10:27:22
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[IEEE 2019 International Conference on Opto-Electronics and Applied Optics (Optronix) - Kolkata, India (2019.3.18-2019.3.20)] 2019 International Conference on Opto-Electronics and Applied Optics (Optronix) - Design of High-Performance LED Based Integrating Sphere for Illumination & Communication
摘要： An integrating sphere has been specially designed using multiple white light LEDs mounted on both the inner and outer surfaces of the sphere to create improved uniform illumination inside a computer laboratory room. The LEDs are simultaneously used as optical transmitters of trans-receiver systems for indoor optical wireless communication. More uniformity of light helps to develop better access to wireless communication systems, comfortable movement inside the room and reduced shadowing effect in wireless communication. One integrating sphere fitted with LED arrays divided among outer and the inner surfaces of the sphere is able to create ideal uniformity conditions for illumination and data communication within a volume (3 x 3 x 3) m3 of laboratory space. The system is capable of bidirectional full-duplex communication using IR LEDs as source for uplink and silicon photodiodes as receivers for optical wireless communication links. The theory and the design principles of the integrating sphere and the optical wireless communication link design would be presented.
关键词： integrating sphere,optical communication,wireless communication,uniform illumination,white light LED
更新于2025-09-11 14:15:04
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Comparison of DCO-OFDM, ADO-OFDM, HDC-OFDM and HNC-OFDM for Optical Wireless Communications
摘要： This paper presents a new form of orthogonal frequency division multiplexing (OFDM) termed as hybrid noise cancelled asymmetrically clipped optical OFDM (HNC-OFDM) for optical wireless communication. This HNC-OFDM is formed by combining the concepts of noise cancelled asymmetrically clipped optical OFDM and DC biased optical OFDM (DCO-OFDM). HNC-OFDM has the same bit error rate (BER) performance and dimming flexibility but less complexity compared to the recently developed hybrid diversity combined OFDM. The optimum DC bias level for HNC-OFDM, DCO-OFDM and asymmetrically clipped DC biased optical OFDM is shown to depend on the target BER, the constellation size, the received signal to noise power ratio, the proportion of DCO-OFDM element, the link type, equalization, etc. Simulations results show that with an optimum bias, HNC-OFDM can outperform others in an average power limited channel, while DCO-OFDM is a better choice for a peak power limited channel.
关键词： optical wireless communication,Dimming,LiFi,visible light communication,OFDM
更新于2025-09-11 14:15:04
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Photon-Counting Underwater Wireless Optical Communication by Recovering Clock and Data From Discrete Single Photon Pulses
摘要： To realize a long-distance underwater communication by using low-cost light emitting diode (LED) and single photon avalanche diode (SPAD), we proposed a method for recovering clock and data directly from discrete random pulse sequences output by SPAD. On this basis, a new communication model is established, taking into account not only ?uctuations in photon ?ux and quantum ef?ciency of photon detection in a time-slot, but also the phase difference of the recovered clock caused by it. A photon-counting underwater optical wireless communication (UOWC) system was built. The effects of the system setting parameters such as the number of gating signals, synchronous character length and baud rate on the average bit error rate (BER) were veri?ed by experiments. The experimental results show that under condition of only average 10 photons in one time-slot, photon-counting UOWC with a BER of 3.51 × 10?4 and a baud rate of 1 Mbps can be achieved.
关键词： clock synchronization,Underwater optical wireless communication (UOWC),photon-counting,data recovery
更新于2025-09-11 14:15:04
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[IEEE 2018 International Topical Meeting on Microwave Photonics (MWP) - Toulouse (2018.10.22-2018.10.25)] 2018 International Topical Meeting on Microwave Photonics (MWP) - Spatial Diversity Gain of Micrometer-scale MIMO FSO Transceivers utilizing Multicore Fiber and 2-D Photodetector Array
摘要： Feasibility of a high-capacity spatially-multiplexed free-space optical (FSO) communications system utilizing small-footprint spatial diversity transceivers based on multicore fiber and 2-D photodetector array is investigated. With the aid of MIMO-DSP, the micrometer-scale spatial diversity transceivers enable 37-Gbps 2x4 MIMO-FSO transmission over strongly-correlated optical MIMO channels.
关键词： Free space optics MIMO,Space-division multiplexing,Spatial diversity,Optical wireless communication
更新于2025-09-11 14:15:04
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[IEEE 2019 7th International Conference on Information, Communication and Networks (ICICN) - Macao, Macao (2019.4.24-2019.4.26)] 2019 7th International Conference on Information, Communication and Networks (ICICN) - A Photon Counting Underwater NOMA Wireless Optical Communication System
摘要： In recent years, Underwater wireless optical communication (UWOC) has become one of hot spots of human exploration of the unknown deep-sea space. In this paper, a shot noise limited interleaver iterative non-orthogonal multiple access (NOMA) UWOC system with photon counting is proposed. The characteristics of underwater receiver wireless optical channel are studied. In addition to single receiver scheme, a diversity receiving scheme is also considered. According to the result of simulation, the proposed multi-user system can perform well in very low receiving signal energy, which achieves the bit error rate (BER) performance of 2*10e-5 at 40 photon number per bit for 4-user scenario with 1/10 repetition coding rate. Moreover, this system also has the rapid convergence and good receiving diversity property.
关键词： underwater optical wireless communication,NOMA,photon counting
更新于2025-09-11 14:15:04
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[IEEE 2018 11th International Symposium on Communication Systems, Networks and Digital Signal Processing (CSNDSP) - Budapest (2018.7.18-2018.7.20)] 2018 11th International Symposium on Communication Systems, Networks & Digital Signal Processing (CSNDSP) - Spatial Interpolation of Optical Wireless Impulse Responses
摘要： In this paper, spatial interpolation is proposed as a time-saving technique for the estimation of the different Optical Wireless Impulse Responses which result from the nodes’ position changes in the mobility modeling of wireless optical communications. Typically, in this kind of analysis, the time-dependent impulse response is calculated numerically at each point of the path. However, this approach may result prohibitive due to the computation time. In this work, a support domain distributed on the moving area is defined, and accurate impulse responses for the domain’s points are obtained using a Monte Carlo Ray Tracing algorithm. Then, using this support, Lagrange interpolation method is applied for quick calculation out-of-the-support positions’ impulse responses. In this way, the impulse response for those points included in nodes’ path can be obtained without a high time and computational cost. The Lagrange interpolants were essayed with successful results, suggesting that the proposed technique may become relevant in upcoming statistical modeling in mobility situations.
关键词： Spatial Interpolation,Impulse Response,Lagrange Interpolation,Monte Carlo Ray Tracing,Optical Wireless Communication
更新于2025-09-11 14:15:04
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Outage and error analysis of three hop hybrid VLC/FSO/VLC-based relayed optical wireless communication system
摘要： In this paper, we consider a three hop hybrid visible light communication/free space optical/visible light communication (VLC/FSO/VLC) system in which the information is transmitted from a room inside the building on a VLC link toward the decode and forward (DF) relay attached to that building. The relay maps the incoming signal on the FSO link and forwards it to the other DF relay attached to the second building, which further passes it down to the user inside the room onto the VLC downlink. The VLC and FSO links follow the Lambertian emission model and Gamma-Gamma fading statistics, respectively, under the impact of atmospheric turbulence, pointing errors, semiangle, and field of view of the detector. The performance of the three hop hybrid system is derived in terms of the closed-form expression for the outage probability. The error performance is analyzed in terms of average symbol error probability of the considered hybrid system. Furthermore, an expression for asymptotic outage probability of the system is derived to investigate the behavior of the system at high signal-to-noise ratio (SNR) regimes. The impact of variation in the parameters on the hybrid VLC/FSO//VLC communication system performance is illustrated by the numerical plots.
关键词： free space optical,relayed optical wireless communication,outage probability,average symbol error probability,visible light communication
更新于2025-09-10 09:29:36