| 题名 | 基于通道切换的相干激光通信探测技术研究 |
| 作者 | 刘福川 |
| 学位类别 | 硕士 |
| 答辩日期 | 2015 |
| 授予单位 | 中国科学院上海光学精密机械研究所 |
| 导师 | 孙建锋 |
| 关键词 | 相干探测 内差 通道切换 时钟恢复 |
| 其他题名 | Research on Coherent Laser Communication Detection Scheme Based on Channel-switching Method |
| 中文摘要 | 相干探测相比直接探测，理论上可以使系统达到散粒噪声限，改善系统接收灵敏度。无论是在光纤通信中，还是自由空间激光通信中，为实现高灵敏度高速率数据传输，相干探测方案越来越受到重视。本论文主要的工作就是围绕光通信相干探测进行的相关研究。具体围绕以下几方面工作进行： 1.对光纤通信中相干探测方案进行调研，综述了相干探测方案的发展历程及进展情况。另外也调研了自由空间激光通信的进展情况，直接探测仍为主要方案，但相干探测方案也有所发展。 2.针对幅度调制（ASK）、二进制相位调制（BPSK）对相干探测的零差、外差探测方案分别进行了分析与对比。对于BPSK调制解调，内差探测方案可以降低探测器带宽，而且不需要本振和信号光的锁相环相位同步，这种方案成为较现实的相干探测实现方案。 3.针对BPSK-内差探测，提出了基于通道切换的解调方案，从原理上证明了可行性，理论上，灵敏度相比零差探测下降3dB至6dB。然后根据原理对该方案进行了实验验证,该方案可以成功恢复出数据。该方案相比数字相干光接收机方案，无需高速模数转换器和数字信号处理器，实现结构上更简化。 4.对基带信号数字化过程中必不可少的时钟恢复部分进行了简单分析。其实现基于闭环控制思想。鉴相器得到误差，经过环路滤波器的校正环节，控制本地振荡器输出。最后对速率为10Gbps，采样率为40G Sa/s的通道切换实验数据进行了处理，数据处理的结果也间接说明了时钟恢复对信号数字化采样的重要性。 |
| 英文摘要 | The receiver sensitivity in optical communication is improved by coherent detection schemes which could reach the shot-noise limit，as compared with an ordinary direct detection system. To achieve high data rate transmission，coherent detection schemes are becoming the focus in both optical fiber communication and free space laser communication. The main work of this paper is on the research of coherent detection, and we mainly discuss this technology in the following aspects: 1.The advances in the research on optical fiber coherent communication systems are reviewed. In free space laser communication, the research on coherent detection is increasing while direct detection is still the main choice. 2.Homodyne, heterodyne detection scheme with ASK and BPSK modulation are analyzed. For BPSK, the intradyne detection scheme without the need of a receiver with high bandwidth or an OPLL becomes a realistic detection scheme. 3.A new intradyne detection scheme based on channel switching method is proposed. The principle of this detection scheme is presented. Moreover, the comparison of the sensitivity of this scheme with that of homodyne detection is discussed. An experimental setup was constructed to verify the proposed detection scheme. Without the need for high-speed ADC and DSP, this coherent detection scheme could be realized with simpler structure. 4.The indispensable clock recovery part in the process of digitizing the baseband signal is analyzed, which is no more than a control closed loop comprised of phase detector, loop filter and local oscillator. In addition, the resampling clock in the channel-switching experiment with 10Gbps data rate and 40G Sa/s sampling rate is evaluated which demonstrates the necessity of the clock recovery part. |
| 语种 | 中文 |
| 内容类型 | 学位论文 |
| 源URL | [http://ir.siom.ac.cn/handle/181231/16904]  |
| 专题 | 上海光学精密机械研究所_学位论文 |
| 推荐引用方式 GB/T 7714 | 刘福川. 基于通道切换的相干激光通信探测技术研究[D]. 中国科学院上海光学精密机械研究所. 2015. |
| 个性服务 |
| 查看访问统计 |
| 相关权益政策 |
| 暂无数据 |
| 收藏/分享 |
除非特别说明，本系统中所有内容都受版权保护，并保留所有权利。
修改评论