软切换链路下的混合编码与副载波调制方案  

Hybrid coding and subcarrier modulation scheme in soft-switching links

作　　者：邵军虎[1,2] 孙莹 刘晓楠 苏润民 SHAO Junhu;SUN Ying;LIU Xiaonan;SU Runmin(Faculty of Automation and Information Engineering, Xi'an University of Technology, Xi'an 710048, China;Xiamen Key Laboratory of Mobile Multimedia Communications(Huaqiao University), Xiamen 361021, China)

机构地区：[1]西安理工大学自动化与信息工程学院,西安710048 [2]厦门市移动多媒体通信重点实验室(华侨大学),厦门361021

出　　处：《激光技术》2019年第3期329-334,共6页Laser Technology

基　　金：国家自然科学基金资助项目(61405157);陕西省自然科学基础研究计划资助项目(2017JM6070);陕西省教育厅自然科学专项资助项目(17JK0575);陕西省重点研发计划资助项目(2017ZDCXL-GY-05-03);厦门市移动多媒体通信重点实验室(华侨大学)开放基金资助项目(HQUCOM17-02)

摘　　要：为了提高自由空间光/射频(FSO/RF)混合通信链路的性能,采用混合低密度奇偶校验(LDPC)编码与副载波相移键控/正交振幅调制(PSK/QAM)联合调制的方法,对不同传输比例下混合系统的误比特率性能进行了仿真分析,取得了不同信道条件下单链路和混合链路传输方案的误比特率数据。结果表明,在弱中强湍流条件下采用副载波二进制相移键控(BPSK)调制,相比开关键控(OOK)调制可获得大约4.4dB～5.2dB的增益。采用软切换的混合LDPC编码与副载波BPSK/16QAM调制方案,依据链路状态调整比例为1∶1和3∶1时,不同湍流强度下可获得大约0.3dB～7.4dB的性能增益。这一研究结果对于提高FSO/RF混合通信系统的全天候高效可靠传输性能具有重要的参考价值。In order to improve the performance of free space optical/radio frequency(FSO/RF) hybrid communication links, one modulation method combining hybrid low density parity check (LDPC) coding with subcarrier phase shift keying/quadrature amplitude modulation(PSK/QAM) was adopted. Bit error ratio(BER) performance of hybrid systems with different transmission ratios was simulated and analyzed. BER data of single link and mixed link transmission schemes under different channel conditions were obtained. The results show that subcarrier binary phase shift keying (BPSK) modulation used in weak, moderate and strong turbulence can obtain gain about 4.4dB to 5.2dB compared with on-off keying (OOK) modulation. One soft-switching modulation scheme of hybrid LDPC coding and subcarrier BPSK/16QAM is adopted. When the ratio is adjusted to 1:1 and 3:1 according to link state, performance gains about 0.3dB to 7.4dB can be obtained under different turbulence intensities. This research result has important reference value for improving all-weather efficient and reliable transmission performance of FSO/RF hybrid communication systems.

关 键 词：光通信 自由空间光/射频链路 混合低密度奇偶校验编码 副载波调制 混合调制 

分 类 号：TN929.12[电子电信—通信与信息系统] TN911.3[电子电信—信息与通信工程]