- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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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) - High-Energy Ultrafast Yb-Fiber Laser System Based on a Mamyshev Regenerator
摘要： A ?exible orthogonal frequency division multiplex (OFDM)-based modulation scheme is proposed under the name of Flexible Con?gured OFDM (FC-OFDM). It enables a ?exible subband con?guration and targets a multi-service scenario, which is envisioned for future 5G networks. The proposed FC-OFDM scheme provides a good compromise between the ?lter bank multi-carrier with offset quadrature amplitude modulation and the classical cyclic pre?x-based OFDM system. The detailed system structure is illustrated in this paper, together with ef?ciency evaluations.
关键词： 5G,FBMC,?exibility,waveform,OFDM,multicarrier modulation,OQAM,multi-service
更新于2025-09-19 17:13:59
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Scaled-time OFDM experiments for channels exceeding the cyclic prefix
摘要： Wireless communications experiments at high user velocities can be performed with much less effort at lower velocities by using time-stretching techniques. time-stretching techniques do not consider the case of channel impulse responses exceeding the length of the cyclic prefix (CP). This is the case in any real-world OFDM system. In particular, multipath scenarios caused by relay nodes commonly found in public railways have a late, strong channel tap. In this work, the authors propose a time-stretching technique that preserves the effects of the insufficient CP with negligible error and without channel knowledge.
关键词： cyclic prefix,time-stretching,wireless communications,OFDM,high user velocities
更新于2025-09-19 17:13:59
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[IEEE 2019 Device Research Conference (DRC) - Ann Arbor, MI, USA (2019.6.23-2019.6.26)] 2019 Device Research Conference (DRC) - Defect characterization of InAs/InGaAs quantum dot photodetector grown on GaAs-on-V-grooved-Si substrate
摘要： We present the experimental implementation of an all-optical ROADM scheme for routing of an individual subchannel within an all-optical OFDM superchannel. The different functions required of optical node were demonstrated using interferometric technique with the extraction, drop, and addition of individual subchannel in a ten subchannels optically aggregated signal. The scheme we reported enables a fully ?exible node compatible with future terabit per second superchannel transmission.
关键词： optical communication,All-optical node,all-optical OFDM,interferometer,?exible optical networks,subcarrier multiplexing
更新于2025-09-19 17:13:59
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[IEEE ICASSP 2020 - 2020 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP) - Barcelona, Spain (2020.5.4-2020.5.8)] ICASSP 2020 - 2020 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP) - The Effect of Power Allocation on Visible Light Communication Using Commercial Phosphor-Converted Led Lamp for Indirect Illumination
摘要： Visible light communication (VLC) systems should be designed to provide illumination and wireless data services simultaneously. To achieve this goal at a reasonable cost, the use of Phosphor-Converted (PC) LEDs for indirect illumination should be favored to provide a homogeneous and reliable coverage in the whole service area. Unfortunately, PC-LEDs found in the market so far have not been designed for data transmission; moreover, the response of the other (electro-)optical components of the VLC link are far from ideal. In this paper, we estimate the data rate that is feasible with VLC when indirect illumination is used. For this purpose, the end-to-end response of the VLC link is first modeled using actual measurements of the spectral power distribution of a PC-LED lamp and the ceiling reflectance. Then, different power allocation schemes are studied assuming an optical OFDM waveform. As commercial LEDs have a relatively slow time response, the equivalent VLC channel that results has strong frequency selectivity; therefore, notable data rate gains are achievable when water filling power allocation is applied.
关键词： Optical OFDM,Visible Light Communication,Illumination,Power Allocation,PC-LEDs
更新于2025-09-19 17:13:59
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Ultra-Compact Coupling Structures for Heterogeneously Integrated Silicon Lasers
摘要： Clipping is one of the simplest peak-to-average power ratio reduction schemes for orthogonal frequency division multiplexing (OFDM). Deliberately clipping the transmission signal degrades system performance, and clipping mitigation is required at the receiver for information restoration. In this paper, we acknowledge the sparse nature of the clipping signal and propose a low-complexity Bayesian clipping estimation scheme. The proposed scheme utilizes a priori information about the sparsity rate and noise variance for enhanced recovery. At the same time, the proposed scheme is robust against inaccurate estimates of the clipping signal statistics. The undistorted phase property of the clipped signal, as well as the clipping likelihood, is utilized for enhanced reconstruction. Furthermore, motivated by the nature of modern OFDM-based communication systems, we extend our clipping reconstruction approach to multiple antenna receivers and multi-user OFDM. We also address the problem of channel estimation from pilots contaminated by the clipping distortion. Numerical findings are presented that depict favorable results for the proposed scheme compared to the established sparse reconstruction schemes.
关键词： multi-user communication,Bayesian sparse signal estimation,Clipping,OFDM,PAPR reduction,channel estimation
更新于2025-09-19 17:13:59
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[IEEE 2019 26th IEEE International Conference on Electronics, Circuits and Systems (ICECS) - Genoa, Italy (2019.11.27-2019.11.29)] 2019 26th IEEE International Conference on Electronics, Circuits and Systems (ICECS) - Polymer Microwave Fiber: a New Communication Concept That Blends Wireless, Wireline and Optical Communication
摘要： In this paper, we consider an orthogonal frequency division multiplexing communication system that adopts frame-by-frame transmission in high-speed railway (HSR) scenario. Due to the increase in demand for the QoS sensitive services, an efficient QoS-aware transmission strategy that improves the system performance is required urgently. Many efforts have been devoted to addressing this problem with the assumption of block fading channel in a frame duration. However, due to the frequent channel quality variation in a frame duration and serious inter channel interference in HSR scenario, the throughput of the QoS sensitive services degrades severely. Hence, a robust cross-layer transmission strategy that combines adaptive modulation (AM) scheme with truncated automatic repeat request protocol is proposed. In this cross-layer formulation, the normalized average throughput is optimized subject to the average power and the packet loss rate (PLR) requirements. First, we derive the closed form average bit error rate that represents the PLR requirement at the physical layer. Second, we obtain the solution of robust AM scheme and power allocation policy in the case of continuous rate. Third, we present the adaptive bits and power allocation scheme in the case of discrete rate, which can be implemented in practice. Finally, the performance of the proposed transmission strategy is evaluated by extensive simulations. Comparing with the constant transmit power AM scheme, the throughput increases by 20%, which demonstrates that the proposed robust cross-layer design is suitable for the HSR communication systems.
关键词： OFDM systems,Adaptive modulation,robust cross-layer design,QoS,fast time-varying fading channel,high-speed railway,packet loss rate
更新于2025-09-19 17:13:59
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Optical Transparent Antenna Array Integrated with Solar Cell
摘要： We present the experimental implementation of an all-optical ROADM scheme for routing of an individual subchannel within an all-optical OFDM superchannel. The different functions required of optical node were demonstrated using interferometric technique with the extraction, drop, and addition of individual subchannel in a ten subchannels optically aggregated signal. The scheme we reported enables a fully ?exible node compatible with future terabit per second superchannel transmission.
关键词： interferometer,optical communication,all-optical OFDM,All-optical node,?exible optical networks,subcarrier multiplexing
更新于2025-09-19 17:13:59
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[IEEE 2019 18th International Conference on Optical Communications and Networks (ICOCN) - Huangshan, China (2019.8.5-2019.8.8)] 2019 18th International Conference on Optical Communications and Networks (ICOCN) - Long Distance IM/DD Transmission with OFDM-QAM based Quantum Noise Stream Cipher
摘要： We propose a QAM-based quantum noise stream cipher (QNSC) scheme for IM/DD transmission employing orthogonal frequency division multiplexing (OFDM) modulation. 2.5Gbit/s IMDD-OFDM signal is demonstrated over 1000 km distance. The experimental results show that Q penalty using IMDD-OFDM based QNSC is only 1.6 dB compared to QPSK without encryption in the cases of back-to-back condition and 1000km transmission.
关键词： orthogonal frequency division multiplexing (OFDM),quantum noise stream cipher (QNSC),intensity modulation/direct detection (IM/DD)
更新于2025-09-16 10:30:52
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[IEEE 2019 18th International Conference on Optical Communications and Networks (ICOCN) - Huangshan, China (2019.8.5-2019.8.8)] 2019 18th International Conference on Optical Communications and Networks (ICOCN) - A Novel Chaos-Based Three-Dimensional Constellation Rotation Encryption Algorithm for OFDM-PON
摘要： A physical layer security encryption algorithm in combines proposed OFDM-PON three-dimensional constellation and chaotic mapping. The numerical results show that it has high security and better BER performance compared with traditional two-dimensional modulation.
关键词： OFDM-PON,Three-dimensional mapping,Constellation Rotation,Chaos
更新于2025-09-16 10:30:52
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[IEEE 2019 18th International Conference on Optical Communications and Networks (ICOCN) - Huangshan, China (2019.8.5-2019.8.8)] 2019 18th International Conference on Optical Communications and Networks (ICOCN) - Fiber Nonlinearity Equalizer using MLP-ANN for Coherent Optical OFDM
摘要： We propose a novel artificial neural network nonlinearity equalizer based on multiple layers perceptron(MLP-ANN NLE) for16-quadrature amplitude modulation (16-QAM) coherent optical orthogonal frequency division multiplexing (CO-OFDM) system. The scheme is effective for compensating for the four-wave mixing effect among subcarriers. Compared with the situation of non-compensated nonlinearity, this proposed scheme can increase the Q factor by 1.4 dB and 0.6 dB at 600 km and 2000 km respectively and the transmission distance can be increased by 400 km. It also shows a strong robustness in nonlinearity compensation.
关键词： OFDM,Fiber optical communication,Nonlinearity effect
更新于2025-09-16 10:30:52