光学学报, 2019, 39 (7): 0706002, 网络出版: 2019-07-16
OFDM-OAM光信号在大气湍流中的传输 下载: 1234次
Propagation of OFDM-OAM Optical Signal in Atmospheric Turbulence
图 & 表
图 1. OFDM-OAM-FSO系统示意图。(a)系统结构图;(b)叉形光栅图;(c)扭曲的螺旋相位图
Fig. 1. Diagram of OFDM-OAM-FSO system. (a) System structure; (b) forked grating; (c) distorted spiral phase
图 2. OFDM数据处理过程。(a)发送端OFDM生成过程;(b)接收端OFDM处理过程
Fig. 2. Processing of OFDM. (a) Generation of OFDM at transmitter; (b) processing of OFDM at receiver
图 3. Turbo码编译过程。(a) Turbo编码器结构;(b) Turbo译码器结构
Fig. 3. Turbo code/decode processing. (a) Structure of Turbo coder; (b) structure of Turbo decoder
图 4. 经过不同α值下的non-Kolmogorov湍流模型的相位图及相应的解调光强图。(a)(c)(e) Cn2=3×10-13 、Cn2=4.5×10-14、Cn2=5×10-15时的扭曲螺旋相位图;(b)(d)(f)对应于(a)(c)(e)的解调光强图
Fig. 4. Phase diagrams and corresponding demodulated intensity diagrams based on non-Kolmogorov turbulence model with different α. (a)(c)(e) Distorted spiral phase diagrams for Cn2=3×10-13, Cn2=4.5×10-14, Cn2=5×10-15; (b)(d)(f) demodulated intensity diagrams corresponding to Figs. 4(a)(c)(e)
图 6. 不同α值对应的接收光功率。(a)不同Cn2条件下的接收光功率;(b)不同OAM模式的接收光功率
Fig. 6. Received power as a function of α. (a) Received power for different Cn2; (b) received power for different OAM modes
图 7. 不同湍流条件下的比特误码率。(a)不同Cn2值下的误码率;(b)不同α值下的误码率
Fig. 7. Bit error rates in different turbulence conditions. (a) Error rate as a function of Cn2; (b) error rate as a function of α
图 8. α=3.8时接收信号的星座图。(a) Cn2=3×10-13; (b) Cn2=4.5×10-14; (c) Cn2=5×10-15
Fig. 8. Constellations of received signal when α=3.8. (a) Cn2=3×10-13; (b) Cn2=4.5×10-14; (c) Cn2=5×10-15
图 9. α=3.8时不同接收光功率下的误码率。(a) 不同Cn2值对应的误码率;(b) Cn2=5×10-15时使用信道编解码前后的误码率
Fig. 9. Error rates under different received powers when α=3.8. (a) Error rates for different Cn2; (b) error rates with or without channel coding when Cn2=5×10-15
表 1OFDM参数
Table1. OFDM parameters
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刘旻雯, 李迎春. OFDM-OAM光信号在大气湍流中的传输[J]. 光学学报, 2019, 39(7): 0706002. Minwen Liu, Yingchun Li. Propagation of OFDM-OAM Optical Signal in Atmospheric Turbulence[J]. Acta Optica Sinica, 2019, 39(7): 0706002.