【作者】 王莉；

【导师】 黄永清；

【作者基本信息】 北京邮电大学 ， 电磁场与微波技术， 2011， 硕士

【摘要】 波分复用(WDM)技术能充分利用光纤的带宽,解决通信网络传输能力不足的问题,具有广阔的发展前景。另外,WDM对网络的扩容升级,实现超高速通信等均具有十分重要的意义。光探测器是WDM解复用接收的关键器件,具有平顶陡边响应的光探测器可以降低WDM波长信道间的串扰,提高对信道光检测的快速性和准确性。本论文的工作就是围绕具有平顶陡边响应的光探测器开展的,取得以下研究成果：1、对可变滤波腔长RCE型光探测器进行了研究,研究表明将RCE型光探测器的滤波腔分成两种厚度,选择合适的厚度参数可实现平顶陡边的滤波特性。对双吸收层RCE型光探测器的原理及器件结构进行了分析,与传统的单吸收层RCE探测器相比,具有双吸收层结构的RCE型光探测器量子效率明显提高。2、设计了一种具有可变滤波腔长和双吸收层结合的平顶陡边RCE型光探测器。器件结构是采用通过两种厚度的滤波腔,同时结合双吸收层的结构实现了具有高量子效率谱的“平顶陡边”光谱响应,对器件的量子效率进行了仿真和分析,研究了器件的性能受关键参数的影响。理论仿真结果得到,该器件结构的量子效率能达到68%,平顶部分量子效率的平顶起伏度约为0.38%。0.5dB、3dB、20dB带宽分别为0.1nm、0.14nm和1.13nm。该器件具有高量子效率,同时其光谱响应具有良好的平顶陡边特性。3、研究了一种电路控制法实现光探测器的平顶陡边光谱响应。此电路由放大器、比较器和与逻辑门组成。具有波长选择特性的光探测器结合此电路可得到光探测器的平顶陡边光谱响应。对电路控制法的工作原理进行了详细分析,并完成电路的设计和制作。4、对电路控制法进行了实验验证,一组实验得到的平顶陡边响应范围为1546nm-1549.3nm,0.5dB、3dB、20dB带宽分别为2.76nm、3.29nm和4.58nm；另一组实验得到的平顶陡边响应范围为1554.8nm-1557.6nm,0.5dB、3dB、20dB带宽分别为3.19nm、2.89nm和3.06nm。实验结果验证了该电路控制法可以实现光探测器较好的平顶陡边光谱响应。更多还原

【Abstract】 Wavelength-division multiplexing which makes full use of fiber bandwidth can solve the transmitting deficiency problem of communication networks, and has wide promising prospect. Besides, in the aspects of network expanding, upgrading and the realization of ultra-high speed communications, WDM also has significant meanings. Photodetector is the key device of wavelength demultiplexing and receiving technology in WDM system. Photodetector with flat-top and steep-edge response can reduce the crosstalk between wavelengths and improve the rapidity and accuracy of channel optical detection. The key content of the paper is on photodetector with flat-top and steep-edge response. The research findings are as follows:1、Research on variable filter cavity length (RCE) photodetector indicates that the flat-top and steep-edge response can be realized by the filter cavity with two kinds of lengths and selection of appropriate lenghs. The principle and structure of dual-absorption (RCE) photodetector are discussed. Compared with conventional (RCE) photodetector,dual-absorption (RCE) photodetector has higher quantum efficiency.2、A RCE photodetector with flat-top and steep-edge response based on variable filter cavity and dual-absorption structure is designed. The flat-top and steep-edge response with high quantum efficiency is obtained by variable filter cavity with two different lengths and dual-absorption structure. The quantum efficiency and the effection of the critical parameters are analyzed. Simulation results show that the quantum efficiency value in bandpass are about 68%, the extent of flat top is about 0.38%; 0.5dB,3dB, and 20dB bandwidth are 0.1 nm,0.14nm, and 1.13nm respectively. The photodetector has high quantum efficiency, and good flat-top and steep-edge response.3、A circuit control method achieving the flat-top steep-edge response of photodetectors is researched. The response is realized using three wavelength selective photodetectors and the circuit which consists of amplifiers、comparators and a AND gate. The work principle of the circuit control method is detailedly analyzed and the design of the circuit is completed.4、Experimental verification of the circuit control method is carried out. In group 1, the flat-top steep-edge response is from 1546nm to 1549.3nm and 0.5dB,3dB,20dB bandwidths are 2.76nm,3.29nm, 4.58nm respectively. In group 2, the flat-top steep-edge response is from 1554.8nm to 1557.6nm and 0.5dB,3dB,20dB bandwidths are 3.19nm, 2.89nm,3.06nm respectively. The results of experiments show that the desirable flat-top steep-edge response can be gained.更多还原