基于SLIPT的水下自供电光通信系统设计  

Design of Underwater Optical Communication System based on Simultaneous Light⁃wave Information and Power Transmission

作　　者：张丽娟 夏艳 赵茜 李丹丹 ZHANG Lijuan;XIA Yan;ZHAO Qian;LI Dandan(School of Data and Science,Guangzhou Huashang College,Guangzhou 511300,China)

机构地区：[1]广州华商学院数据与科学学院,广州511300

出　　处：《光通信研究》2024年第3期11-17,共7页Study on Optical Communications

基　　金：广州华商学院青年学术基金资助项目(2021HSQS52)。

摘　　要：【目的】对水下通信系统的供电系统进行能量补充通常非常昂贵且不切实际,基于太阳能电池的水下同步光波信息和功率传输(SLIPT)通信系统可在通信的过程中同步完成能量的收集,是水下传感通信系统自供电强有力的解决方案。但商用硅太阳能电池通信带宽十分有限,且容易在水下光衰减效应时出现信噪比深衰落的现象。【方法】文章采用一种负偏压的太阳能电池光接收器方案,将硅太阳能电池的-3 dB带宽从420 kHz提高到768 kHz。对于水下环境中各种退化效应造成信噪比衰减的现象,采用了一种低峰均功率比(PAPR)的离散傅里叶变换扩展正交频分复用(DFT⁃S⁃OFDM)调制方案,抵消了系统中的深衰落现象。【结果】分别对比了不同浑浊度(吸收特性和散射特性)的水环境中的DFT⁃S⁃OFDM与OFDM调制系统的性能,扩频后的OFDM调制方案更具有鲁棒性。【结论】实验表明,在白光发光二极管(LED)连续照射3 h下,能量收集系统的电池总电力效率可提高1.87倍,实现了通信过程中的能量同步收集。【Objective】Replenishing the power supply system of an underwater communication system is usually very expensive and impractical.The underwater Simultaneous Light⁃wave Information and Power Transmission(SLIPT)communication sys tems based on solar cells are powerful solutions.However,the communication bandwidth of the silicon solar cell receiver is very limited,and it is easy to have the phenomenon of deep fading of the Signal⁃to⁃Noise Ratio(SNR)due to the underwater light at tenuation effect.【Methods】For these problems,this manuscript employs a negative⁃biased solar cell light receiver scheme that in creases the-3 dB bandwidth of silicon solar cells from 420 kHz to 768 kHz.Aiming at the deep fading of SNR caused by various degradation effects in the water environment,a Discrete Fourier Transfor(DFT)extended Orthogonal Frequency Division Multi plexing(OFDM)modulation scheme with a low peak⁃average power ratio is adopted to offset the deep fading phenomenon in the system.【Results】The performance of DFT Spread OFDM(DFT⁃S⁃OFDM)and OFDM modulation systems in water environ ments with different turbidity(absorption and scattering characteristics)is compared.It is shown that the DFT⁃S⁃OFDM modu lation and demodulation system is more robust.【Conclusion】Finally,experiments have shown that the total battery power effi ciency of the energy harvesting system can be increased by 1.87 times under continuous illumination of white LEDs for 3 h,realiz ing synchronized energy harvesting in the communication process.

关 键 词：水下无线光通信 同步光波信息和功率传输 光伏负偏压 离散傅里叶变换扩展正交频分复用 

分 类 号：O438[机械工程—光学工程]