【作者】 胡智勇；

【导师】 李世忱；

【作者基本信息】 天津大学 ， 物理电子学， 2004， 博士

【摘要】 光纤放大器技术和光源技术是 DWDM 传输系统的核心技术。本论文主要围绕宽带光纤放大器技术、多波长光源技术和可调谐光源技术取得如下研究成果:一、宽带 EDFA 的理论分析与实验研究1. 使用模拟软件 OptiAmplifier 4.0 对 L 波段 EDFA 的本征增益平坦特性及级联结构的作用机理进行了详细的分析与优化设计,并给出了特定条件下的本征增益平坦的近似计算公式,实验获得的结果与数值模拟符合很好。2. 使用并联结构进行了 C+L 宽带 EDFA 的实验研究,小信号增益大于 20 dB,可用带宽约 70 nm(1530~1561 nm,1567~1607 nm)。二、宽带 FRA 与宽带 EDFA/FRA 混合放大器的数值模拟1. 数值模拟了 7 个波长泵浦的宽带增益平坦 FRA,通过合理配置泵浦波长和泵浦功率,可实现 80 nm(1530~1610 nm)范围内±0.5 dB 的平坦增益。2. 数值模拟了分立式 EDFA/FRA 混合放大器,结合增益均衡滤波器,对设定的多波长信号得到了 75 nm (1530~1605 nm)范围内约 22.7 dB 的平坦增益。三、多波长半导体光放大器-光纤环形腔激光器(SFRL)实验研究1. 报道了一种基于 SOA 的结构简单的新型双波长 SFRL,其中以两个中心波长不同的 FBG 作为选频滤波器,在室温下实现了稳定的双波长输出。2. 以 F-P 腔做为梳状滤波器的多波长 SFRL,在室温条件下得到了具有高信噪比、窄线宽、高稳定度的 7 个波长输出,峰值功率相对起伏小于 4%3. 利用高双折射光纤环形镜(Hi-Bi FLM)的梳状滤波特性的多波长 SFRL,在室温下获得了基本符合 ITU 标准 100 GHz 的 15 个波长以上的输出,线宽 0.1 nm,各信道峰值功率相对起伏小于 12%四、可调谐光纤激光器的研究1. 宽可调谐 SOA 基高双折射环形腔激光器:在 SFRL 的腔内串接一段高双折射光纤,通过调节腔内偏振控制器和偏振片,获得了 1555~1604 nm 范围的可调谐激光输出。我们获得的 L 波段可调谐,以及 49 nm 的宽可调谐范围,在国内外均属首次。2. 离散可调谐掺铒光纤环形腔激光器:使用高双折射光纤环形镜和一个选择信道的可调谐薄膜滤波器,获得了 C 波段 41 个离散波长的可调谐输出,各信道波长输出的功率起伏几乎为零。更多还原

【Abstract】 The optical fiber amplifiers and light sources are key devices in densewavelength division multiplexing (DWDM) transmission systems. This dissertation isfocused on broad-band fiber amplifiers and light sources for optical communication,which include:1. Broad-band erbium-doped fiber amplifiers (EDFA) 1) The intrinsic flat gain characteristics and dual-stage configuration mechanics of L-band EDFA are investigated by Optiwave corporation’s simulation software (OptiAmplifier 4.0). Without gain equalized filter (GEF), gain spectrum is flat on optimum population inversion level and low noise less than 6 dB is achieved with the configuration. 2) Experimental investigation on C+L band with parallel configuration is carried out, and a novel simple structure is proposed. The small signal gain and band width are obtained more than 20 dB and 70 nm, respectively.2. Broad-band Raman fiber amplifiers and hybrid EDFA/FRA 1) The optimal design method for flat-gain broad-band FRA is presented using OptiAmplifier 4.0. With seven proper pumps, the relative gain flatnesses are all less than ±0.5 dB within the bandwidths of 80 nm (1530~1610 nm). 2) A finely gain-flattened broad-band hybrid amplifier is simulated by using OptiAmplifer 4.0. With an extremely large seamless bandwidth of 75 nm (1530-1605 nm) and a significantly enhanced optical signal-to-noise ratio, the hybrid amplifier is realized using a discrete FRA, a C-band EDFA, and a gain equalizer.3. Multiwavelength SOA-fiber ring lasers (SFRL) 1) A FBG based dual wavelength SFRL is proposed using two different central wavelength FBGs, which act as frequency selective filters. And at room temperature, stable dual wavelength is obtained. 2) Based on SOA and F-P comb filter, seven wavelengths are obtained in the ring-cavity configuration, with high stability and the wavelength spacing about 2.7 nm. The SNR of each channel is more than 29 dB and the output power relative fluctuation ratio is less than 4%. II<WP=4>ABSTRACT 3) We propose a novel switchable multiwavelength fiber ring laser based on SOA, which uses a Hi-Bi fiber loop mirror (Hi-Bi FLM) as filter. More than 15 wavelengths with linewidth about 0.1 nm spacing on ITU-grid (100GHz) are obtained, and the output power relative fluctuation ratio is less than 12%.4. Tunable fiber ring lasers 1) We demonstrate a novel approach to obtain a narrow linewidth laser with 35 dB sidemode suppression by utilizing a SOA in a fiber unidirectional ring that consists of a linear polarizer, 1.28 m Hi-Bi fiber and polarization controllers. The laser has a widely tuning range of 49 nm (1555~1604 nm), which is the best result with similar method until now. 2) A wavelength-selectable discretely tunable erbium-doped fiber laser in C-band is fabricated using a precise multi-wavelength grid filter (Hi-Bi FLM) and a channel-selecting tunable filter. With 41 channel operation of ~100 GHz channel spacing, the laser is suitable for DWDM sources.更多还原