直接调制光反馈半导体激光器产生超宽带信号  

Generation of ultra-wideband signals by directly current-modulating distributed feedback laser diode subjected to optical feedback

作　　者：刘明[1,2] 张明江[1,2,3] 王安帮[1,2] 王龙生[1,2] 吉勇宁[1,2] 马喆[1,2] 

机构地区：[1]太原理工大学,新型传感器与智能控制教育部重点实验室,太原030024 [2]太原理工大学光电工程研究所,太原030024 [3]东南大学,毫米波国家重点实验室,南京210096

出　　处：《物理学报》2013年第6期222-231,共10页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:60927007;60908014;61108027);国家重点基础研究发展计划(批准号:2010CB327806);中国博士后科学基金(批准号:2011M500048);山西省高等学校优秀青年学术带头人支持计划(批准号:2012lfjyt08);光电信息技术教育部重点实验室(天津大学)开放基金(批准号:2012KFKT004))资助的课题~~

摘　　要：利用直接电流调制光反馈半导体激光器产生了符合美国联邦通信委员会关于室内无线通信频谱限定的超宽带(UWB)微波信号.基于光反馈半导体激光器速率方程组,数值分析了偏置电流、反馈强度对混沌UWB脉冲信号的影响.研究表明,混沌UWB脉冲频谱的10dB带宽分别随着偏置电流的增大和反馈强度的增强而逐渐增加;中心频率分别随着偏置电流的增大和反馈强度的增强而逐渐增大.实验中,产生了中心频率为6.6GHz,10dB带宽为9.6GHz的混沌UWB信号.进一步,通过调节偏置电流和反馈强度,可实现混沌UWB信号的中心频率和10dB带宽的可调谐输出,实验结果和数值分析相符合.此外,实验产生的混沌UWB信号经过34.08km的光纤传输后,其频谱形状几乎没有发生变化,表明该方法所产生的混沌UWB信号对光纤色散有较大的容忍度.The chaotic ultra-wideband （UWB） pulse signals are generated by directly modulating semiconductor laser subjected to optical feedback. We simulate that the -10 dB bandwidth and the central frequency of the RF spectrum of the chaotic UWB signals are influenced by the bias current and feedback strength. The research results demonstrate that the -10 dB bandwidth of the RF spectrum of the UWB signals increases with the increases of the bias current of the semiconductor laser and the feedback, the central frequency also increases with the increases of the bias current and the feedback. In our experiments, chaotic UWB signals with steerable and flatted power spectrum are generated by directly modulating DFB-LD subjected to optical feedback. The power spectrum of UWB signals is fully compliant with the FCC indoor mask, while a large fractional bandwidth of 133% and a central frequency of 6.6 GHz are achieved. The central frequency and -10 dB bandwidth of the chaotic UWB signals are on a large scale tunable by adjusting the bias current and feedback power. In addition, the chaotic UWB signals transmit through a 34.08 km single mode fiber and the power spectrum does not have any discrete spectrum line.

关 键 词：超宽带 混沌激光 光反馈 直接调制 

分 类 号：TN248.4[电子电信—物理电子学]