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.     

Generation of an ultra-wideband triplet signal based on semiconductor optical amplifier

We propose a novel ultra-wideband (UWB) triplet signal source based on the cross-gain modulation (XGM) in semiconductor optical amplifier (SOA). In the proposed scheme, only an optical source and two SOAs are needed, so the all-optical structure is compact. A triplet optical pulse with center frequency of 6.25 GHz and fractional bandwidth of 83% is obtained by the scheme. The extinction ratio can be improved by the counter-propagating scheme. The triplet pulse signal with only one wavelength can be easily controlled, and can aviod the dispersion effect. The output triplet pulse signal is insensitive to the light wavelength shifts, its available wavelength range is wide, the dynamic range of the input power is more than 6 dBm, and the bias current of the SOAs is exhibited.     

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。     

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...     

全光超宽带正相和反相monocycle信号源的研究

基于半导体光放大器( SOA)中交叉增益调制(XGM)效应,同时全光实现超宽带(UWB)正相、反相高斯单边信号(monocycle).输出的monocycle脉冲只包含一个波长分量,在光纤传输过程中monocycle上下脉冲不会引入时间差.利用光通信系统软件OptiSystem对方案进行仿真,分析了光源波长对输出monocycle脉冲的影响,结果表明输出的monocycle脉冲具有对光源变化不敏感的优点.     

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。     

Optical UWB doublet pulse generation using multiple nonlinearities of single SOA

All-optical ultra-wideband (UWB) doublet pulse generation based on the multiple nonlinear effects of a single semiconductor optical amplifier (SOA) is demonstrated. First, a monocycle pulse is obtained by means of cross-gain modulation and self gain-saturation in the SOA, and a Gaussian pulse at conjugated light is obtained using four-wave mixing of the SOA. Secondly, the Gaussian pulse at the conjugated light is combined with the monocycle pulse by proper time delay to form a doublet pulse. The central frequency and 10 dB bandwidth of the doublet radio frequency are 5 and 6.25 GHz, respectively. The scheme is simple since only a single SOA is required.     

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。     

不同陡峭边沿的皮秒光脉冲经半导体光放大器后的时域特性分析

分析了具有不同徒峭程度边沿的皮秒光脉冲通过半导体光放大器后输出脉冲的时域特性，其中着重考虑了输出脉冲的峰值功率和脉冲宽度的变化。结果表明：输出脉冲的峰值功率、脉冲宽度与输入脉冲的峰值功率、输入脉冲边沿的徒峭程度以及半导体光放大器的偏置电流密切相关。     

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。     

半导体光放大器对超短光脉冲频谱特性的影响

为进一步理解半导体光放大器工作的物理本质,从速率方程出发,采用分段模型数值分析了超短光脉冲经SOA后的输出频谱和由SOA产生的附加啁啾特性。结果表明：SOA引起的附加啁啾是与SOA的偏置电流、初始信号脉冲的波长、脉冲形状、峰值功率以及脉冲宽度等因素有关;对应的输出脉冲的频谱形状也与上述因素密切相关。     

基于半导体光放大器环形腔的全光频率倍增/恢复

提出了一种利用具有干涉作用的半导体光放大器(SOA)环形腔实现全光频率倍增/恢复的新方法,该方法同相关实验比较具有显著优势.数值结果表明:2.5 GHz的光脉冲序列注入SOA环形腔,可输出重复频率为5～25 GHz振幅均衡、与入射光偏振无关的光脉冲序列;SOA的偏置电流对SOA环形腔输出脉冲振幅的均衡度影响显著,对于基频为2.5 GHz和10 GHz输入脉冲序列分别存在一最佳的SOA偏置电流值;从传输速率为2.5 Gbit/s的27-1伪随机信号中可提取出重复频率为分别2.5 GHz和5 GHz的幅度均衡的时钟信号.     

1kHz全光纤双程结构掺Yb3+脉冲光纤放大器

以1KHz低重复频率的脉冲激光为信号光源,实验研究了全光纤双程结构的脉冲光纤放大器.利用光纤声光调制器(AOM)滤除了放大过程产生的放大自发辐射光(ASE),并测量了该ASE功率;分析了低重复频率及双程结构对放大器输出特性的影响;研究了抽运光功率对输出脉冲宽度和脉冲峰值功率的影响.在注入信号激光波长1060nm、脉冲宽度10.2ns、峰值功率0.58W时,获得放大脉冲激光的脉冲宽度7.9ns、峰值功率245.2W,对应增益26.3dB.     

Increasing input power dynamic range of SOA by shifting thetransparent wavelength of tunable optical filter

Gain-saturation-induced self-phase modulation (SPM) leading to pulse distortion in a semiconductor optical amplifier (SOA) is overcome by shifting a tunable optical filter (TOF). A recovered or broadened pulse can be obtained after filtering the amplified pulse in the SOA even if the short pulse is only 2-3 ps long. The input power dynamic range (IPDR) can be strongly increased by shifting the TOF and the direction of the shifted transparent wavelength is different for 10 Gb/s return-to-zero (RZ) or nonreturn-to-zero (NRZ) signals. The transparent wavelength of the TOF should be shifted to a longer wavelength for RZ signals and to a shorter for NRZ signals. 80-Gb/s optical time division multiplexing (OTDM) signal amplification in the SOA is demonstrated for the first time. We also demonstrate that a large IPDR for the 80-Gb/s OTDM signal can be obtained by shifting the TOF     

半导体光放大器的增益透明电流测量方法研究

半导体光放大器(SOA)作为全光集成器件的核心,在全光通信和光纤传感等领域中具有重要的应用前景。值得关注的是,半导体光放大器的材料增益透明决定了它的快慢光过渡点和信号增益的起始点,因此准确测量其材料增益透明对应的注入电流,对于SOA的全面应用具有重要意义。提出了一种测量SOA材料增益透明电流的方法,并深入分析了其特点。依据材料增益透明时SOA的输出功率与入射光偏振无关的特性,实验测量了不同输入光功率条件下,入射光偏振态对输出功率影响最小时,SOA的注入电流。利用上述方法,准确地测量出给定波长输入待测SOA的增益透明电流为155mA。该方法为实现其他类型任意波长注入时SOA增益透明电流的测量提供了参考,为其全面应用奠定了基础。     

Pulse extraction and kW peak power generation with the nonlinearoptical loop mirror in an erbium-doped fiber amplifier chain

The nonlinear optical loop mirror is used to suppress optical noise and residual coherent background between repetitive short optical pulses. An input pulse power fraction of only 0.6% is improved to 80% at the output of the device. The device is passive and, in principle, independent of wavelength, pulse width, pulse repetition rate, and input signal polarization. This technique can be used to generate high peak power pulses using a cascade of optical amplifiers. Here we report the generation of 140 ps square pulses with 2 kW peak power (0.3 μJ) at a repetition rate of 10 kHz     

波分复用-光时分复用波长转换信号的消光比研究

对基于半导体光放大器(SOA)交叉增益调制(XGM)效应的全光波分复用一光时分复用(WDM—OTDM)转换后的两路时分复用输出信号的消光比(ER)特性进行了分析。研究了两路波分复用的输入抽运光和探测光的功率、波长、抽运光的消光比、数据速率以及半导体光放大器的偏置电流、腔长和模场限制因子对转换信号消光比的影响。模拟结果表明，增大抽运光输入功率，选择长波长抽运光，可以增加转换光相应信道消光比，但减小了相邻信道的输出消光比；增加抽运光消光比，可以提高转换光消光比，但各个信道增长幅度不同；减小探测光输入功率，选取短波长探测光波长，增加半导体光放大器的腔长和模场限制因子以及大的偏置电流可提高转换光消光比；对于两路或多路波分复用信号转换时分复用信号的过程中，一定要考虑转换光每个信道消光比的均衡。     

TOAD中半导体光放大器的动态增益响应及光脉冲研究

讨论了太赫兹光非对称解复用器中半导体放大器（ＳＯＡ）对具有不同能量和脉宽的控制脉冲的动态增益响应，研究了不同的逆时针信号脉冲和控制脉冲时延的民政部下通过ＳＯＡ后的地针信号脉冲的功率和相位变化。     

TOAD中半导体光放大器的动态增益响应及光脉冲传输特性研究

讨论了太赫兹光非对称解复用器中半导体光放大器 (SOA)对具有不同能量和脉宽的控制脉冲的动态增益响应 ,研究了不同的逆时针信号脉冲和控制脉冲时延的情况下通过 SOA后的逆时针信号脉冲的功率和相位变化。