基于XGM的QD-SOA全光波长转换特性的研究

发布时间：2018-01-16 03:17

本文关键词：基于XGM的QD-SOA全光波长转换特性的研究　出处：《曲阜师范大学》2015年硕士论文　论文类型：学位论文

【摘要】：随着互联网和通信网中各种数据业务需求的快速增加,我们已进入大数据时代,如云计算,物联网等。下一代通信网的趋势是一种高效、高速、大容量、智能交换的全光网络。波长转换技术是全光网络的关键技术,可以提高全光网的波长利用率,降低网络阻塞,实现各种数据业务的不同协议转换和透明传输。一般,量子点半导体光放大器(quantum-dot semiconductor optical amplifier,QD-SOA)具有优异的非线性特性,如阈值电流低、微分增益高、温度灵敏性低等,被广泛应用。基于QD-SOA交叉增益调制效应(cross-gain modulation,XGM)的全光波长转换技术实现简单容易,转换效率较高,一直作为研究的重点。但基于双端耦合QD-SOA的波长转换器制作工艺困难,自发辐射噪声较高,消光比退化严重,因此本文提出了一种基于单端耦合QD-SOA型结构的全光波长转换器。基于QD-SOA-XGM的全光波长转换原理,本文分别介绍了QD-SOA的静态和动态分段模型,首先计算了双端耦合QD-SOA全光波长转换器的主要特性,如消光比、增益恢复时间和啁啾。然后计算了单端耦合QD-SOA全光波长转换器变换光的消光比,并对比了双端耦合方案下的变换光消光比。主要内容包括以下几方面:1、简述了全光波长转换技术对全光通信系统的意义以及国内外研究概况。提出单端耦合QD-SOA-XGM型结构的全光波长转换器作为研究对象。2、基于QD-SOA基本原理,分别建立静态及动态数值分析模型。详细介绍了Newton法和四阶Runge-Kutta法的主要内容。重点分析了单端及双端两种方案下,QD-SOA有源区的静态特性,包括载流子浓度分布和增益特性。3、以QD-SOA-XGM的全光波长转换原理为基础,采用Newton法和四阶Runge-Kutta法求解速率方程和光场传输方程完成了双端耦合方案下QD-SOA全光波长转换。详细分析了双端耦合QD-SOA-XGM全光波长转换的基本特性,如增益恢复时间(gain recovery time,GRT)、消光比(extinction ratio,ER)和啁啾(Chirp)。(1)对QD-SOA的GRT进行数值研究。仿真结果显示增大注入电流、增大探测光功率、增加有源区长度、增大辅助光功率、减小横截面积,都可以缩短QD-SOA的GRT。(2)详细分析了双端耦合QD-SOA自身及外部参数对变换光ER的影响。计算结果显示增大注入电流、增大泵浦光功率、增大腔长、减小探测光功率和波长转换间隔均能增大变换光ER。(3)对双端耦合QD-SOA的变换光Chirp的影响因素进行数值计算。结果显示增加信号脉宽、减小注入电流、泵浦光ER和线宽增强因子均会减小变换光啁啾值。此外,减小泵浦光功率和增大探测光功率均减小变换光Chirp,但是输入信号的波长对Chirp影响不大。实际应用中设置QD-SOA自身及外部参数时必须考虑啁啾效应的影响,以减小误码率。4、单端耦合方案下,分析了QD-SOA自身及外部参数对变换光ER的影响。计算结果显示增加泵浦光功率,减少探测光功率和波长转换间隔,增加注入电流和有源区长度均能增加变换光ER。此外探测光较小时,增大后端面反射率使单端耦合QD-SOA变换光消光比增大,当探测光值较大时,增大端面反射率使单端耦合QD-SOA变换光消光比减小。比较分析了单端耦合方案和双端耦合方案下变换光的ER,结果表明单端耦合QD-SOA波长转换器的转换光ER较大,说明此结构有效提高了变换光消光比的特性,较双端耦合方案是一种改进。
[Abstract]:With the rapid increase of various data services of Internet and communication network, we have entered the era of big data, cloud computing, networking and so on. The trend of next generation communication network is a kind of high efficient, high speed, large capacity, all-optical network intelligent switching. Wavelength conversion is a key technology of all-optical network, can improve the utilization the rate of all-optical network wavelength, reduce network congestion, different protocol conversion to achieve a variety of data services and transparent transmission. Generally, quantum dot semiconductor optical amplifier (quantum-dot semiconductor optical amplifier, QD-SOA) has excellent nonlinear characteristics, such as low threshold current, high differential gain, low temperature sensitivity, QD-SOA cross gain is widely used. Based on the modulation effect (cross-gain modulation, XGM) all-optical wavelength conversion technology is simple and easy to implement, high conversion efficiency, has been as the focus of the study. But based on the double end The coupling of QD-SOA wavelength converter production process difficult, spontaneous emission noise of high extinction ratio degradation is serious, so this paper puts forward a kind of all-optical wavelength converter with single port coupled type QD-SOA structure based on wavelength conversion using QD-SOA-XGM based on the principle, this paper introduces the segmentation model of QD-SOA static and dynamic, the main characteristics of double end coupling optical QD-SOA wavelength converter was firstly calculated, such as extinction ratio, gain recovery time and chirp. Single port coupled QD-SOA all-optical wavelength converter transforms the light extinction ratio is then calculated, and compared the transform of optical extinction double end coupling scheme than. The main contents include the following aspects: 1, the technology of all-optical wavelength conversion optical communication system and the significance of the research situation at home and abroad. The all-optical wavelength converter with single port coupled QD-SOA-XGM type structure as the research object of.2, based on QD-SOA basis The principle, established the static and dynamic numerical analysis model was introduced in detail. The main content of Newton method and four order Runge-Kutta method. Focus on the analysis of the single or double two schemes, QD-SOA static characteristics of the active region, including the distribution of the carrier concentration and gain characteristics of.3, based on the principle of wavelength conversion using QD-SOA-XGM using Newton method, and four order Runge-Kutta method for solving the rate equation and light propagation equations completed the double end coupling scheme of QD-SOA all-optical wavelength conversion. A detailed analysis of the double end coupling QD-SOA-XGM all-optical wavelength conversion characteristics, such as the gain recovery time (gain recovery time GRT (extinction), the extinction ratio of ratio, and ER) chirp (Chirp). (1) the numerical study of QD-SOA GRT. The simulation results show that increasing the injection current increases, probe power, increase the length of the active region, increasing the auxiliary optical power, reducing cross-sectional area, all Can shorten QD-SOA GRT. (2) the effect of double end coupling QD-SOA itself and external parameters on the detailed analysis of the optical ER transform. The calculation results show that increasing the injection current, increasing the pump power increases, the cavity length, lower probe power and wavelength conversion interval can increase the optical ER. transform (3) numerical calculation of double factors port coupled QD-SOA transform of optical Chirp effect. The results show that increasing the pulse width of the signal, reduce the injection current, the pump ER and the linewidth enhancement factor decreases with transform of optical chirp values. In addition, decrease and increase detection optical power decreased Chirp transform of optical pump power, but the input signal wavelength has little effect on Chirp. QD-SOA itself and the external parameter in the practical application must consider the influence of chirp effect, to reduce the error rate of.4, the single end coupling scheme, analyzes the influence of QD-SOA itself and external parameters on the optical transform ER. Meter Results show that increasing the pump power, probe power and reduce conversion interval, increase the length of injection current and the active region can increase ER. in addition to transform of optical probe light is small, after increasing the reflectivity that the single end coupling QD-SOA transform optical extinction ratio increases, when the probe is large, increasing the reflectivity ratio decreases. Single port coupled QD-SOA transform light extinction. A comparative analysis of the transform of optical coupling scheme and single ended double end coupling scheme under ER, results show that the conversion of single port coupled QD-SOA optical wavelength converter ER is large, indicating that this structure can effectively improve the transform of optical extinction ratio characteristics of a double end coupling scheme is an improvement.

【学位授予单位】：曲阜师范大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TN929.1

【参考文献】