In order to ensure stable,correct and real-time high-speed transmission of indoor visible light communication(VLC),the key modulation and demodulation technologies of orthogonal frequency division multiplexing(OFDM) a...In order to ensure stable,correct and real-time high-speed transmission of indoor visible light communication(VLC),the key modulation and demodulation technologies of orthogonal frequency division multiplexing(OFDM) are studied in this paper. The time-domain synchronization,frequency synchronization and channel equalization of receiver are analyzed and optimized by utilizing short and long training preamble. Moreover,field programmable gate array(FPGA) development board(Xilinx Kintex-7) and Verilog hardware description language are used to realize the design of proposed OFDM-VLC system. Simulation and experiment both verify the feasibility of the hardware designs of this system. The proposed OFDM-based VLC system can process signal in real-time,which can be used in actual VLC application systems.展开更多
A practical demodulation of multiplexed wavelength FBGs is proposed. The detection wavelength of adjacent FBGs and the wavelength resolution are discussed. Experimental results show the wavelength resolution is 0.01nm...A practical demodulation of multiplexed wavelength FBGs is proposed. The detection wavelength of adjacent FBGs and the wavelength resolution are discussed. Experimental results show the wavelength resolution is 0.01nm and strain resolution is 8.27× 10-6.展开更多
基金supported by the National High Technology Research and Development Program of China(863 Program)(No.2015AA033303)the National Key Basic Research Program of China(973 program)(No.2013CB329204)+1 种基金the National Nature Science Foundation of China(Nos.61178051,61321063 and 61335010)the Science and Technology Project of Guangdong Province in China(No.2014B010120004)
文摘In order to ensure stable,correct and real-time high-speed transmission of indoor visible light communication(VLC),the key modulation and demodulation technologies of orthogonal frequency division multiplexing(OFDM) are studied in this paper. The time-domain synchronization,frequency synchronization and channel equalization of receiver are analyzed and optimized by utilizing short and long training preamble. Moreover,field programmable gate array(FPGA) development board(Xilinx Kintex-7) and Verilog hardware description language are used to realize the design of proposed OFDM-VLC system. Simulation and experiment both verify the feasibility of the hardware designs of this system. The proposed OFDM-based VLC system can process signal in real-time,which can be used in actual VLC application systems.
文摘A practical demodulation of multiplexed wavelength FBGs is proposed. The detection wavelength of adjacent FBGs and the wavelength resolution are discussed. Experimental results show the wavelength resolution is 0.01nm and strain resolution is 8.27× 10-6.
