1.25-Gb/s Operation of a Spectrum-Sliced Fabry–PÉrot Laser Diode With Intensity Noise Suppression by a Second Fabry–PÉrot Laser Diode

We propose a low-cost solution for the intensity noise suppression in the spectrum-sliced Fabry-Perot laser diode (F-P LD), which is achieved by placing an F-P LD at the receiver region. The F-P LD at the receiver region provides the intensity noise suppression of about 10 dB as well as the increase of the received optical power for the spectrum-sliced optical signal. The Q-factor is improved about 5.9 at a data rate of 1.25 Gb/s. As a result, we successfully demonstrate 10-km error-free transmission at 1.25-Gb/s signal with a transmission penalty of less than 0.5 dB. It is also found that the low spectrum-sliced power of -22 dBm achieves the relative intensity noise level of -112.5 dB/Hz, which is almost independent of the operation current.     

1.25-Gb/s Operation at 50-GHz Channel Spacing Based on Intensity Noise Suppression of Wavelength-Locked Fabry–PÉrot Laser Diode

We demonstrate 1.25-Gb/s operation at 50-GHz channel spacing and 10-km single-mode fiber, which is based on a wavelength-locked Fabry-Perot laser diode (F-P LD) and an intensity noise suppression by a gain saturation of F-P LD in front of the receiver. The wavelength-locked F-P LD employs the spectrum-sliced incoherent light with narrow bandwidth of 35 GHz. The intensity noise of wavelength-locked F-P LD is suppressed about 6 dB by the F-P LD in the front of the receiver. As a result, the bit-error-rate curves exhibit the error-free performances over the detuning conditions to cover a whole mode spacing period of F-P LD.     

A Simple and Color-Free WDM-Passive Optical Network Using Spectrum-Sliced Fabry–PÉrot Laser Diodes

We propose and demonstrate a simple and color-free wavelength-division-multiplexing passive optical network (WDM-PON) using spectrum-sliced Fabry-Perot laser diodes (F-P LDs). Due to its low front facet reflectivity (~0.1%), the F-P LD shows a broadband lasing spectrum and reduced mode partition noise. By utilizing multiple peaks that are separated by the free-spectral range of the cyclic arrayed waveguide gratings, the 16-channel WDM-PON is successfully demonstrated at 155 Mb/s.     

Noise Characteristics of a Wavelength-Locked Fabry–Perot Laser Diode

We derived a theoretical model of a wavelength-locked Fabry–Perot laser diode (F-P LD) to a sliced spectrum of externally injected amplified spontaneous emission (ASE) from wave equations. The model explains the dynamics of the wavelength-locked F-P LD. Using this model, we investigated the noise characteristics of a wavelength-locked F-P LD with respect to the various parameters, such as, the injected ASE power, the bias current of F-P LD, and the wavelength detuning. We also investigated intensity noise increment by spectral filtering in optical access networks based on wavelength-locked F-P LDs.      

Investigation of a Rate-Selectable All-Optical Packet Clock Recovery System

This letter presents the experimental performance of a rate-selectable all-optical packet clock extractor using a Fabry-Perot (F-P) filter, a semiconductor optical amplifier (SOA), and polarization interferometers (PIs). The F-P filter with a low finesse and a free-spectral range (FSR) equal to the lowest packet data rate was used to directly extract the packet clock from the packet data stream, which ensures that the clock locks fast and vanishes quickly. Different PIs, in conjunction with the F-P filter, were used to form comb filters with different FSRs in order to suppress the undesired subharmonic frequencies. The clock then goes into SOA to reduce the low-frequency amplitude noise. We demonstrate packet clock extraction at 10, 20, and 40 Gb/s with the combination filter.     

Broad-band light source using mutually injected Fabry-Pe/spl acute/rot laser diodes for WDM-PON

We propose and demonstrate a new broad-band light source (BLS) for a wavelength division multiplexing-passive optical network (WDM-PON) based on the wavelength locked Fabry-Pe/spl acute/rot laser diodes (F-P LDs). By mutual injection between two antireflection-coated F-P LDs, we realized a broad-band light with a low relative intensity noise. By using the proposed BLS for wavelength locking of the F-P LD, we achieve color-free operation of the optical network termination with Manchester coded data. We also demonstrate a WDM-PON based on the proposed BLS.     

基于高精细度F-P滤波器的40Gb/s全光时钟提取

提出了一种基于高精细度Fabry-Perot(F-P)滤波器的全光时钟提取方案,并进行了实验验证。为了实现对信号波长无关的特性,系统利用光纤中交叉相位调制(XPM)效应对输入信号进行正码波长变换,使变换后的波长始终与F-P滤波器的透射峰精确对准。采用精细度为1 012的高精细度F-P滤波器提取时钟,并利用半导体光放大器(SDA)的自增益调制(SGM)效应进一步抑制时钟信号的低频噪声,保证了高质量的时钟输出。实验中,利用这种装置对40 Gb/s归零(RZ)码信号进行了时钟提取,得到了抖动为285 fs的高质量40 GHz时钟信号,验证了方案的可行性。     

基于F-P滤波器的多波长时钟提取

提出一种简单的全光单一链路的多波长时钟同时提取方案。利用Fabry-Perot(F-P)滤波器对波分复用(WDM)系统中多波长的归零(RZ)码信号进行时钟提取,滤波器后面接半导体光放大器(SOA)对F-P滤波器提取出的时钟进行整形处理,通过实验证实了用F-P滤波器对两路不同波长的10 Gbps信号时钟提取的可行性以及同一SOA同时处理双波长时钟的能力,两路提取时钟的单边带相位噪声分别达到-82.815和-83.072dBc/Hz@10 kHz。     

TDM-PON上行信号光功率均衡器的锁模特性

为了减小时分复用无源光网络（TDM-PON）上行信号光波长的飘移,基于TDM-PON上行信号光功率均衡器架构,采用单模激光注入锁定光网络单元（ONU）法布里-珀罗（F-P）激光器（LD）方法,研究了F-P LD输出光波长的锁模特性,包括锁模的范围、驱动电流对锁模特性的影响、锁模前后温度变化引起F-P LD光波长变化情况等。结果表明,当驱动电流为9mA时,F-P LD可被锁模的波长范围为0.38nm,大于ONU上行光波长因环境温度变化5℃而产生的波长位移量0.25nm,F-P LD被锁模可使ONU上行信号的光波长相同且稳定,降低光功率均衡后的噪声。     

共焦法布里-珀罗干涉显微测头光学特性分析

根据纳米计量分辨力的要求,设计一套共焦法布里-珀罗(F-P)干涉显微测头。系统光源采用保偏光纤直接导入,从F-P腔外入射。光路设计成便于减小光学共模噪音的差动形式。通过建立模型分析系统光学特性,得出反射平板的最佳反射率以及共焦结构对干涉条纹的影响。实验验证表明反射平板反射率为40%时可以使系统得到对比度高,信噪比好的干涉条纹;针孔光阑可以方便寻找测量透镜的焦点和减小杂散光的噪音;系统轴向分辨力达到0.2nm。     

Application of Wavelet Transform in Dual-differential Optical Fiber F-P Interferometric Micro-displacement Measurement System

Based on dual-differential comparing principle, an experimental system of optical fiber F-P interferometric micro-displacement measurement is introduced. It is capable of achieving the absolute displacement measurement, and wavelet transforms is adopted as theory fundament to extract the optical F-P interferometric characteristic signal and remove the noise, so its resolution can reach 0. 01 μm in the dynamic range of 0- 1 mm.     

In-Line Fabry–Perot Etalons Based on Hollow-CorePhotonic Bandgap Fibers for High-Temperature Applications

In this paper, we report a novel in-line fiber Fabry–Perot (F-P) etalon, consisting of a section of hollow-core photonic bandgap fiber (HC-PBGF) spliced between two single mode fibers. The fabrication process of such a sensor is simple and straightforward, including only cleaving and splicing. The sensing characteristics of the F-P etalon based on HC-PBGF, including high temperature, strain, bend, and transverse load, are fully investigated by experiments, for the first time to our knowledge. It is found that such a F-P etalon can be used under high temperatures of up to 600 $ ,,^{circ}{hbox {C}}$, and has a low cavity-length-to-temperature sensitivity of $sim {1.4}~{hbox {nm}}/^{circ}{hbox {C}}$, while it has a relatively high strain sensitivity of $sim {5.9}~{hbox {nm}}/mu varepsilon$. Moreover, this F-P etalon is insensitive to bend or transverse load. Furthermore, the long cavity length ($> {1}~{hbox {cm}}$) of the sensor makes it suitable for multiplexing. These characteristics would make this HC-PBGF-based F-P etalon to be an excellent strain sensor or gas sensor for use in high-temperature environments.      

两路微振动信号的光纤F-P腔干涉测量

法布里-珀罗(F-P)腔传感器结构简单,复用能力强,对导致其腔长发生变化的物理量灵敏度高,在超精密测量领域日益受到重视。为了使用一套光纤F-P腔测量两个目标,设计了两路反馈信号光纤F-P腔干涉系统,同时开展两路微振动信号测量。对两路微振动反馈F-P腔干涉信号,经多次取包络分解,得到了高、低频信号频谱,进而计算出待测目标振幅。实验结果表明,通过低频信号恢复待测目标振幅的误差为1.32%,通过高频信号恢复待测目标振幅的误差为6.63%。该方法有效实现了两路反馈光纤F-P腔干涉信号的分离,拓展了测量通道,提高了抗干扰能力。     

Environmentally Stable Fabry–PÉrot-Type Strain Sensor Based On Hollow-Core Photonic Bandgap Fiber

We design and demonstrate a miniature all-fiber Fabry-Perot (F-P) interferometric sensor based on hollow-core photonic bandgap fiber where the strain is gauged by measuring the spectrum shift of the reflected optical signal. The F-P cavity in the order of millimeters is fabricated by simple techniques of cleaving and fusion splicing. The sensitivity of the sensor is 1.55 pm/muepsiv at the wavelength of 1550 nm and the contrast of the intensity reaches 4-6 dB. Temperature and bend insensitivity and excellent repeatability of the sensor make it convenient for a wide range of applications.     

基于光纤F-P滤波器的全光纤水汽拉曼激光雷达系统的设计与分析

提出并设计了一套基于光纤F-P滤波器的可见波长域全光纤水汽拉曼激光雷达系统,实现对大气水汽和气溶胶的精细探测。讨论了光纤F-P腔内损耗和腔镜反射率对F-P透射谱的细度、峰值透过率以及带宽的影响,得到腔内损耗在小于3%的情况下,光纤F-P滤波器具有较高的峰值透过率（>0.5）和较窄的谱线带宽(<0.9nm)。通过结合光纤带通滤波器和二级级联光纤F-P滤波器的参数设计,在三个独立的光通道中分别实现水汽拉曼信号（660nm）、氮气拉曼信号(606nm)和米瑞利信号(532nm)的窄带宽、高透过率严格滤波,并获得对杂散光的高抑制率。通过系统仿真,对各散射信号强度分布、水汽廓线和探测信噪比进行了数值仿真计算,验证了系统方案的可行性。     

放大自发辐射注入波长锁定法布里-珀罗激光器

波分复用无源光网络(WDM-PON)被认为是接入网的最终解决方案,基于放大自发辐射(ASE)注入波长锁定法布里-珀罗(F-P)激光器的WDM-PON由于其价格低廉和容易实现颜色无关操作而受到极大关注.实验研究了ASE注入波长锁定F-P激光器的ASE增益、边模抑制比(SMSR)和相对强度噪声(RIN)随F-P激光器注入电流和ASE注入功率的变化关系,理论模拟了ASE注入功率和增益一定时,F-P激光器注入电流随其前端面反射率的变化关系,并从实验上进行了验证.研究结果表明,当F-P激光器的注入电流为阈值电流的1.3～1.7倍时,能获得满足应用需要的相对强度噪声和边模抑制比.对于一定的ASE注入功率和输出功率,存在使注入电流最小的最佳前端面反射率.     

Gain measurements of Fabry-Pe/spl acute/rot semiconductor lasers using a nonlinear least-squares fitting method

A method for the measurement of the gain-reflectance product of Fabry-Pe/spl acute/rot (F-P) semiconductor lasers is proposed and compared to other techniques. The method is based on a nonlinear, least-squares fitting of the F-P modes to an Airy function. A separate fitting is performed over each mode, as measured with an optical spectrum analyzer (OSA), so that the gain-reflectance parameters are extracted. The influence of the OSAs response function is considered by convolution of the Airy function with the response function of the OSA. By comparing with the Hakki-Paoli method, the mode sum/min method, and the Fourier series expansion method, we find that the nonlinear fitting method is the least sensitive to noise. However, owing to a broadening of the F-P modes of the semiconductor laser, the mode sum/min method combined with a deconvolution technique gives the least underestimated gain above threshold.     

基于一种新型结构的F-P腔的频标研究

根据ITU-T的信道标准,和F-P腔作为频标的原理,设计制作了一种能兼顾手动大范围调节法布里-珀罗(F-P)腔间距和压电陶瓷(PZT)细调F-P腔间距的两重结构,使得精确调节腔长变得简单易行,从而可以满足频标研究的要求.利用该新型结构的F-P腔,通过反复精细调节最终将其锁定模式控制在1955,此时F-P腔的自由光谱区(FSR)为100GHz,从而获得了一系列符合ITU-T频率标准的人工频标.     

瑞利多普勒激光雷达超窄带滤光器的设计

目前中国科学技术大学车载激光雷达已经实现了对于15~60 km中性大气风场的夜间连续观测,鉴于白天观测的信噪比受到背景光的限制,因此,设计了一种利用现有干涉滤光片结合固态FP标准具的超窄带滤光器,用于实现背景噪声的降低。提出了一种结合鉴频器参数确定FP最佳参数的方法,得出了FP标准具的参数,实现了带宽为8.4 pm、中心波长为354.73 nm、自由光谱间距为150 pm、峰值透过率高于0.67的滤光器,将背景噪声降低到原来的十八分之一。该滤光器有效提高了系统信噪比,减小了风速误差,同时计算了温度、角度变化对滤光器带宽、中心波长和透过率的影响,设计了一种角度调谐的方法。实验结果与理论值具有较高的一致性。     

基于法布里-珀罗微腔的光微流FRET激光产生

为了实现低阈值光微流荧光共振能量转移（FRET）激光,基于制备的高品质因子、高稳定法布里-珀罗（F-P）微腔,采用间接抽运方法研究了两种F-P谐振腔中光微流FRET激光的产生。直接抽运施主染料,使得施主染料通过FRET的方式把能量传递给受主染料,从而实现受主染料的间接能量抽运。结果表明,在此种抽运方式下,F-P光微流激光腔中实现了0.48μJ/mm2的低激光抽运能量密度阈值;并可通过FRET激光产生的形式实现对低浓度物质的检测。