基于SOA中XGM效应全光超宽带高斯单边信号源的研究

提出了一种基于半导体光放大器（SOA）中交叉增益调制（XGM）效应产生高斯单边信号（monocycle）脉冲的方案。该方案只需要单个外部光源和单个SOA,结构简单;采用相向的工作方式可以改善输出信号的消光比;输出的monocycle信号光只含有一个波长,在光纤传输过程中上下脉冲不会引入时间差。利用Optisystern...     

基于SOA和EAM的全光超宽带脉冲波形调制

提出了一种基于半导体光放大器(SOA)和电吸收调制器(EAM)实现超宽带(UWB)脉冲波形调制(PSM)的方案,利用SOA的交叉增益调制(XGM)和增益饱和效应产生高斯单边带(monocycle)信号,利用EAM的交叉吸收调制(XAM)效应控制泵浦光与monocycle信号的叠加,进而实现UWB PSM。与其它方案相比,本文方案具有结构简单、易于控制和色散管理相对简单的优势。利用OptiSystem7.0软件进行了仿真研究,分析了输入信号功率、调制速率和光源波长对UWB PSM信号的影响,研究了UWB PSM信号在光纤中的传输特性。结果表明,本文方案对输入信号波长不敏感。给出了输入信号功率和调制速率的优化范围。     

基于半导体放大器实现多功能超宽带调制的研究

基于半导体放大器(SOA)的增益饱和效应,提出了一种简单的实现多功能超宽带(UWB)调制的方案。方案采用一个光源和单个SOA,可以实现脉冲波形调制(PSM)、脉冲幅度调制(PAM)和脉冲极性调制(BPM),因此实现容易、结构简单和成本低。利用OptiSystem软件对方案进行了仿真研究,分析了各参数对调制信号的影响以及信号的传输特性。结果表明,本方案对光源的波长和光源的光功率的变化不敏感,仿真输出的调制信号在单模光纤(SMF)中可传输35km。     

基于微结构光纤的光纤环激光器

报道了一种基于微结构光纤(MF)的光纤环激光器.通过微调控制信号的频率,激光器实现了稳定的锁模状态,在C波段获得了重复频率为10 GHz、宽度小于8ps的相干光脉冲输出.在该激光器中,采用了掺Er光纤放大器(EDFA)作为腔内增益介质,并使用了25 m长、具有反常色散和高非线性的MF作为脉冲压缩介质.通过调整腔内的带通滤波器中心频率可以实现对工作波长的连续调谐,因此该激光器可作为波分复用(WDM)系统的可调谐光源.     

基于PM 的多功能超宽带调制技术的研究

基于相位调制器(PM)级联高斯带通滤波器,提出了一种超宽带(UWB)多功能调制方案,可以实现通断键控(OOK)、脉冲极性调制(PBM)和脉冲形状调制(PSM)。该方案结构简单,只需单个光源,利用率较高,仅改变比特序列发生器(BSG)的编码就可实现三种UWB调制格式间的灵活切换;产生的三种信号只包含一个波长,在光纤中传输时无需复杂的非线性控制和色散管理。使用光通信软件Optisystem进行模拟,研究了光源功率、调制速率以及两支路PM和滤波器系统误差的影响,对OOK、PBM和PSM信号的传输性能进行了分析。结果表明,光源功率和调制速率在一定范围内变化时,可以获得性能最佳的UWB调制信号。     

基于重叠光栅和啁啾光栅的双波长光纤激光器

研究光寻址电位传感器(LAPS)的器件噪声特性 。通过对LAPS半导体场效应器件的结构分析,建 立LAPS的理论模型,并进一步分析LAPS器件噪声信号的来源、种类及特性。以 pH缓冲液中H离子 浓度为检测对象,搭建基于NI采集卡和Labview环境的LAPS测试系统,对影响LAPS信号噪声 特性的光源 波长、光源调制频率、光源强度和Si衬底厚度等因素进行了仿真和实验研究。结果表明,增 大光源波长和光源强度 是提高输出信号幅值和信噪比(SNR)的最有效方法。     

基于LiNbO3M-Z调制器的UWB信号PAM调制技术研究

提出一种基于LiNbO3Mach-Zehnde调制器(MZM)实现超宽带(UWB)脉冲幅度调制(PAM)的方案,只利用一个LiNbO3-MZM,实现幅度调制,结构简单,易于实现。利用OptiSys-tem7.0软件对方案进行了仿真,研究了调制信号的传输特性,并分析了光源功率、光源波长、脉冲宽度、调制速率、延迟时间以及传输距离对调制信号的影响。     

光寻址电位传感器的噪声特性研究

研究光寻址电位传感器(LAPS)的器件噪声特性 。通过对LAPS半导体场效应器件的结构分析,建 立LAPS的理论模型,并进一步分析LAPS器件噪声信号的来源、种类及特性。以 pH缓冲液中H离子 浓度为检测对象,搭建基于NI采集卡和Labview环境的LAPS测试系统,对影响LAPS信号噪声 特性的光源 波长、光源调制频率、光源强度和Si衬底厚度等因素进行了仿真和实验研究。结果表明,增 大光源波长和光源强度 是提高输出信号幅值和信噪比(SNR)的最有效方法。     

1064nm泵浦温度调谐PPLN光学参量振荡器

对脉冲泵浦的温度可调准相位匹配(QPM)光学参量振荡器(OPO)进行了研究.LD泵浦的声光调Q Nd:YAG激光器输出的1064nm脉冲激光做泵浦源,极化周期为30.7μm的单周期PPLN做光学参量振荡器的参量晶体,通过控制参量晶体的温度可以得到信号光的波长调谐输出.在LD电流17A得到信号光的平均功率最大为230mW,转化效率达13%.     

基于并联SOA的全光广播式超宽带脉冲形状调制技术

基于半导体光放大器(SOA)中交叉增益调制(XGM)效应,采用SOA的并联结构,提出了一种全光产生广播式超宽带(UWB)脉冲形状调制(PSM)信号的方案。该方案同时产生三路超宽带PSM信号,具有多用户传输数据的能力,可为多址通信作理论基础;采用相向的工作方式可以改善输出信号的消光比。利用OptiSystem7.0软件对方案进行仿真,分析了输入信号脉冲宽度、输入光功率和波长对产生的超宽带PSM信号的影响,对信号的传输特性进行了研究。结果表明,本文方案对输入信号脉冲宽度和输入光波长具有良好的容忍度,并且给出了输入光功率的优化范围。     

Multiple ultra-wideband signal sources exploiting XPM in SFRL

A novel scheme for all-optical broadcast ultra-wideband (UWB) monocycle pulses generation based on cross-phase modulation (XPM) in semiconductor fiber ring laser (SFRL) is proposed, in which three UWB positive or negative monocycle pulses can be generated simultaneously. A comprehensive broad-band dynamic model for this kind of all-optical broadcast UWB monocycle sources is established, which is further applied to numerically analyze the impacts of injection current of semiconductor optical amplifier (SOA), the power and wavelength of the signal light on the performance of the UWB positive monocycle pulses with higher power spectral density. The results show that the spectra of the UWB positive and negative monocycle pulses generated by this scheme match the Federal Communications Commission (FCC) definition quite well. Three UWB positive monocycle pulses with better performance can be obtained when the power of signal light is at a high level, and three other UWB positive monocycle pulses with good tolerance to both the injection current of the SOA and the wavelength of the signal light can be obtained. In addition, the powers of the lasing light coupled into the SFRL should not be strong to obtain three UWB positive monocycle pulses with better performance.     

基于半导体光放大器的组播实验研究

提出了一种基于半导体光放大器(SOA)的组播实验方案,首先利用谱展宽和谱切片得到多波长脉冲源,将其作为探测光并与信号光共同注入到SOA中,利用SOA的交叉增益调制(XGM)效应,信号光与每一个波长的脉冲光发生作用,在SOA输出端通过可调光带通滤波器(TBDF)得到每一波长的变换后信号,实现光信号的组播过程。在实验中,10 Gb/s的归零(RZ)码作为信号光,而由多波长脉冲源产生的4波长脉冲光作为探测光,在探测光波长附近分别得到了与编码信号光逻辑取"非"的信号。     

基于光纤XPM光学生成UWB信号的方法

提出了一种基于色散位移光纤(DSF)的交叉相位调制(XPM)效应的超宽带(UWB)光学生成方法。该方法首先利用DSF的XPM效应实现高功率的高斯泵浦光对低功率的直流探测光的交叉相位调制,然后利用光纤布拉格光栅(FBG)对探测光进行鉴频,实现相位调制到强度调制的转换,从而获得单周期UWB信号。利用光子仿真软件对方案进行了仿真实验,得到了中心频率分别为7GHz和6.95GHz、相对带宽分别为143%和145%的UWB信号,验证了所提方法的可行性。同时,研究了输入信号脉冲宽度、FBG的反射率、鉴频器的类型对产生的单周期UWB脉冲信号波形和频谱的影响。仿真实验的结果表明,该方案对输入信号脉冲宽度不是过宽的情况下具有良好的容忍度,光学高斯带通滤波器、波分复用器和FBG等光滤波器均可作为鉴频器,采用FBG优点是可通过改变反射率灵活地调整产生的UWB脉冲信号的波形。     

Photonic Monocycle Pulse Frequency Up-Conversion for Ultrawideband-Over-Fiber Applications

We demonstrate a photonic monocycle pulse frequency up-conversion scheme for ultrawideband (UWB)-over-fiber applications using nonlinear polarization rotation arising in a semiconductor optical amplifier. For the first time, we have successfully realized the photonic up-conversion of UWB monocycle pulses with an optical local oscillator signal at 24 GHz in the whole -band. The up-converted UWB monocycle pulse at 24 GHz exhibits a power spectrum density fitting the UWB emission mask. After electrical down-conversion, the UWB monocycle pulse has shown low distortion induced by the optical mixing process.     

All-optical ultra-wideband doublet signal source based on the cross-gain modulation in a semiconductor optical amplifier

We propose a novel scheme to generate the ultra-wideband (UWB) doublet signal pulse based on the cross-gain modulation (XGM) in a semiconductor optical amplifier (SOA). In the scheme, only an optical source and an SOA are needed. As there is only one wavelength included in the output doublet signal pulse, no time difference between the upper and down pulses is introduced during the transmission process. By using the software of Optisystem 7.0, the impacts of the optical power, the SOA current, the wavelength and the input signal pulse width on the generated doublet pulse are simulated and tudied numerically. The results show that when the pulse width of the input signal pulse is larger, the output signal pulse is better, and is insensitive to the change of wavelength. In addition, the ultra-wideband positive and negative monocycles can be generated by choosing suitable optical source power and SOA current.     

基于粒子群算法的超宽带脉冲波形设计

首先分析了在超宽带系统中高斯脉冲成形因子和微分阶数对其能量谱密度的影响,并在此基础上,为了提高高斯脉冲波形的频谱利用率,采用高斯导函数线性组合来产生脉冲波形,提出并分析了一种基于粒子群（PSO）优化算法的超宽带无线脉冲波形优化设计方法,仿真表明该方法产生的高斯导函数线性组合脉冲能够很好地满足FCC的频谱掩模限制。     

Research of all-optical ultra-wideband triplet signal source based on a single semiconductor optical amplifier

A novel scheme for all-optical ultra-wideband triplet signal pulse generation based on the cross-gain modulation (XGM) in a single semiconductor optical amplifier (SOA) is demonstrated. In this scheme, only one optical source and one SOA are needed, so the configuration is simple. Due to only one wavelength is included in the generated triplet pulse, no time difference between output signal light and probe light is introduced during the transmission process. By using the software of Optisystem 7.0, the impacts of the input signal width, the optical power and the wavelength of the optical source on the generated triplet pulse are numerically simulated and studied. The results show that the proposed scheme has better triplet signal pulse when the input signal pulse width is larger, and it is insensitive to the wavelength change within a certain range.     

Filter-Free Optically Switchable and Tunable Ultrawideband Monocycle Generation Based on Wavelength Conversion and Fiber Dispersion

In this letter, a novel filter-free scheme for all-optical ultrawideband monocycle generation based on wavelength conversion in semiconductor optical amplifier and group-velocity dispersion in single-mode fiber is proposed and experimentally demonstrated. The system is optically switchable in pulse polarity, and tunable in both pulsewidth and radio-frequency spectrum.