用于油气井RFID扶正器激活的阅读器共形天线设计

Design on conformal antenna of reader for RFID centralizer activation in oil and gas wells

基于油气井井下环境的特点,为实现井下扶正器的远程控制,同时改正射频识别(RFID)阅读器天线电磁波强度衰减过大、辐射性能差等缺陷,设计一种共形于井下管道的RFID扶正器阅读器偶极子天线。依据天线设计的基本理论,利用天线弯折技术,将该天线结构设计为倒“U”型,实现与套管相共形;通过仿真扫频分析优化天线参数,分析天线主要结构对性能的影响。结果表明,设计的天线最终的中心频率为860 MHz,在该频率下天线输入端口反射系数为-21.05 dB,增益为2.2 dB,天线尺寸为11 mm×148.44 mm,天线的性能满足设计需求,可用于套管扶正器等井下工具的无线控制。

Based on the characteristics of the downhole environment of oil and gas wells,a dipole antenna was designed and analyzed for radio frequency identification(RFID)conformal to the downhole pipeline to realize the remote control of downhole centralizer and to correct the defects such as excessive attenuation and poor radiation performance of the RFID reader antenna.Based on the fundamental theory of antenna design,the antenna structure was designed as the inverted"U"shape by using the antenna bending technique to achieve the conformal shape with the casing.The antenna parameters were optimized through the simulation frequency sweep analysis,and the influence of the main structure of antenna on the performance was analyzed.The results show that,the final central frequency of the antenna is 860 MHz,the antenna input port reflection coefficient at this frequency is-21.05 dB,the gain is 2.2 dB,and the antenna dimension is 11 mm×148.44 mm.The performance of the antenna meets the design requirements,and it can be applied to the wireless control of downhole tools such as casing centralizer.