光纤延迟线环境适应性及精度研究

发布时间：2018-05-26 22:30

  本文选题：光纤延迟线 + 精度　； 参考：《电子科技大学》2015年硕士论文

【摘要】：引入基于光纤延迟线的光实时延迟(OTTD)移相技术,实现光移相代替电移相可以很好地解决相控阵雷达天线波束偏斜和信号展宽问题,极大地提高雷达的瞬时信号带宽。光纤延迟线在应用过程中,对环境适应能力的优劣直接影响到其所在仪器或装备的性能。研究高精度光纤延迟线及其环境适应性,提高可靠性至关重要。本文首先搭建了基于矢量网络分析仪相位法测量的光纤延迟线研制实验平台,单点光纤延迟精度达±0.1ps。分析磁光开关状态误差,设计和优化延迟线拓扑结构,研制出步进为10ps的高精度5-bit光纤延迟线,延迟精度为±1.1ps,误差均方差为0.68ps,平均插损为5.42dB,幅度一致性为0.49dB。然后,分析了光纤延迟温度特性和磁光开关的经典光路,指出温度发生变化时,引起磁光开关附加损耗的三种原因:温致45?旋光波片旋光角度偏移、温致磁光晶体旋光角度偏移和温致光纤耦合空间错位。结合相应的晶体温度特性及光纤模场耦合效率,公式理论推出这三种原因给磁光开关带来的附加损耗大小,分析发现温度对5-bit光纤延迟线的影响很小。之后,分析了空间辐照环境中光学材料的辐照效应、色心的形成和延迟线器件受辐照后的性能表现。结合硅材料E’色心动力学模型和在前人光纤辐照特性实验的基础上分析了5-bit光纤延迟线辐照特性,并提出抗辐照建议。最后,搭建了5-bit光纤延迟线及其分立元件(光纤、磁光开关、光纤分路器和波分复用器)温度、辐照实验系统。在-5℃~55℃温度范围内,两个磁光开关温致附加损耗分别为0.16dB和0.41dB;光纤分路器和波分复用器的温致附加损耗在0.1dB以内;5-bit光纤延迟线延迟误差为2.2ps,误差均方差为0.4~0.5ps,损耗在5~6dB之间,幅度一致性为1dB,温致附加损耗在0.5dB以内,测试结果显示温度对小步进5-bit光纤延迟线的影响很小。在0~120krad辐照剂量下,光纤延迟线及其分立元件辐照附加损耗不断增加,磁光开关、光纤分路器的辐致损耗在1dB左右,波分复用器在辐致损耗在4dB左右,但是5-bit光纤延迟线辐照附加损耗达到了19dB,并且1.55mm厚度的铝壳不能有效屏蔽辐照给器件带来的损伤。
[Abstract]:The optical real-time delay OTTD phase shifting technology based on optical fiber delay line is introduced to realize optical phase shift instead of electric phase shift, which can solve the problems of antenna beam deflection and signal broadening of phased array radar, and greatly improve the instantaneous signal bandwidth of phased array radar. In the process of application, the adaptability of optical fiber delay lines to the environment has a direct impact on the performance of their instruments or equipment. It is very important to study the high precision optical fiber delay line and its environmental adaptability to improve the reliability. In this paper, the experimental platform of optical fiber delay line based on phase measurement of vector network analyzer is built. The precision of single point fiber delay is 卤0.1 ps. The state error of magneto-optic switch is analyzed, and the topology of delay line is designed and optimized. A high-precision 5-bit fiber delay line with step 10ps is developed. The delay precision is 卤1.1 pss, the error mean square deviation is 0.68 pss, the average insertion loss is 5.42 dB, and the amplitude consistency is 0.49 dB. Then, the delay temperature characteristics of optical fiber and the classical optical circuit of magneto-optic switch are analyzed, and three reasons for the additional loss of magneto-optic switch are pointed out when the temperature changes: temperature-induced 45? The optical rotation angle migration of the rotatory wave plate, the rotation angle migration of the temperature induced magneto-optic crystal and the spatial dislocation of the thermally induced fiber coupling are investigated. Combined with the temperature characteristics of the crystal and the coupling efficiency of the fiber mode field, the additional loss of the magneto-optic switch caused by these three reasons is deduced by the formula theory. It is found that the temperature has little effect on the 5-bit fiber delay line. After that, the radiation effect of optical materials, the formation of color center and the performance of delay line devices after irradiation are analyzed. Combined with the E'color center kinetic model of silicon materials and based on the experiments of previous optical fiber irradiation characteristics, the radiation characteristics of 5-bit fiber delay line are analyzed, and the anti-irradiation suggestions are put forward. Finally, the temperature of 5-bit fiber delay line and its discrete elements (optical fiber, magneto-optic switch, fiber splitter and wavelength demultiplexer) and the irradiation experiment system are built. In the temperature range of -5 鈩，

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