随钻感知金属内孔光纤等离子波导共振正交频分宽带传输研究

In the field of drilling network cloud communication, we proposed the metal fiber made of inner hole of a drill as the transmission carrier of the plasma wave-guide, the information transmission bandwidth is up to hundreds of M bit/s, and the distance is more than 10 kilometers. Relative to the current mud channel, acoustic channel, electromagnetic channel and "water" channel, it can achieve to High speed and long distance transmission of large data sensing system under the shaft with the plasma optical wave. In the plasma optical communication with drilling, using the MIMO-OFDM technology, it can overcome the various frequency shift of the pit optical source and improve the detection sensitivity to enhance the coherent local oscillator. Meanwhile, the double heterodyne detection in optical domain and electric domain is suitable for harsh environment under the shaft. Using the information enhancement method of the coupling principle of light cone resonance wave-guide in metal hole, and the high strength graphene photoresist with plasma physics resonance sensitization medium and high temperature resistance, can improve the coupling efficiency of the connecting parts of the rotating optical wave-guide. It can effectively overcome the interference of drilling environment and realize low loss and fast access of optical sensor to use the graphene photoresist. It satisfies the requirement of high-speed development requirement in the field of drilling network cloud communication, and has important theoretical value and wide application prospect in the field of intelligent oil production and drilling.

在钻井随钻网络化云传感通信领域，提出钻杆内孔构建金属光纤作为等离子光化波导的传输载体，其信息传输带宽达数百M bit/s，距离达10公里以上。相对当前泥浆信道、声信道、地层电磁信道、“水眼”信道，等离子光波能够实现井下大数据传感系统的高速长距离传输。等离子光随钻通信利用MIMO-OFDM技术，其相干本振增强可以克服井下光源的各种频移，提高检测灵敏度，同时光域电域双外差探测适合井下的恶劣环境。利用金属内孔光纤光锥形共振波导耦合原理的信息增强方法，以及具有等离子物理介质共振增敏和耐高温的高强度石墨烯导光胶来提高钻杆旋转光波导连接部位的耦合效率。石墨烯导光胶能够有效克服钻井的环境干扰以及实现光传感器低损耗快速接入。满足了随钻信息网络化云传感高速发展的需求，在智能化采油与钻探等领域具有重要的理论价值和广泛应用前景。

随钻大数据云传感信息：地质物理、化学参数及井下多媒体微观图像；钻井、测井、完井信息的物联网交互感知信息，急需高速率通信。满足随钻云测量高精度智能传感图像跨尺度感知的网络化需求，需要宽带耦合到光纤传输网。。金属光纤钻杆具有超宽的频带和良好的信噪比，可满足速率和带宽呈几何级数增长的需求。.研究内容：（1）构建金属内孔等离子光化波导随钻信息网络传输系统。传感器信号直接共振耦合到等离子光波通信信道，（2）等离子光化光波导构成阵列化信息通信方法，采用MIMO相干OFDM技术保障通信性能。（3）钻杆连接时随钻金属等离子光化波导极抗衰减、等离子光波狭缝效应产生共振接力增益，激光能量在相位和波长二次整合。等离子自聚焦性能来保持光纤连接时的低损耗；利用相移光纤光栅实现等离子光波相位整合，消除波前畸变，实现能量的同相位积累。.得出重要结果、关键数据：采用金属结构空芯光纤的等离子光波导结合MIMO-OFDM通信方法，解决恶劣的钻井工况高干扰条件下高速度宽带传输问题。明确金属太赫兹光波导损耗和结构连接间关系，揭示金属合金成分和等离子光波导频谱吸收的规律。阐明太赫兹光栅和检测器的匹配原理。建立高信噪比等离子波信息传输的网络化方法，完成钻井通信网络化接收技术分析与仿真；进行接收灵敏度和误码率影响的理论研究和仿真研究，为进一步实用化奠定基础。用跟踪自差相干技术克服背景与环境干扰的影响。.关键数据：通信速率：10M比特/秒以上；通信网络工作中断256个；可接入传感器数量256个，接入同步时间1微秒；随钻通信距离3000米；符合损耗要求的接头数量100个以上。.科学意义：①解决日益增长的随钻传感器网络的大数据实时传输速率需求与水波、声学、土壤电磁波带宽的物理极限的矛盾。②随钻光纤网络实现大数据传感网络信息的实时传输问题。③解决钻井环境扰动与金属光纤钻杆接续时敷设与连接引起的耦合衰减的实用化难题。④构建智能钻杆，网络化钻杆和海洋地下矿藏安全污染的感知与监测网络。