原油含水率测量系统中螺旋天线的设计

Design of Helical Antenna Used for Measurement System on Water Content of Crude Oil

针对目前我国原油含水率高的特点,对原油含水率的实时测量研究有着非常重要的研究意义。根据螺旋天线的基本原理设计了一款用于原油含水率测量的收发天线,该天线在2～3 GHz频段内,回波损耗(S_(11))均小于-10 dB,在2.45 GHz频点的传输损耗(S_(12))值为-11.3 dB,仿真增益达到11.4 dB。为了提高测试的精确度,对螺旋天线加了圆锥形的屏蔽罩,仿真结果均满足要求。进一步,根据仿真得到的天线参数制作了3款天线,每款天线的S_(11)在带宽内均满足要求,并对任意两款天线进行S_(12)的测量。测量结果表明,当距离为150 mm时,实测的其中两款S_(12)值为12.1 dB,这与仿真的S_(12)值相近,从而最终选定该组天线作为收发天线。

In view of the high water content of crude oil in our country, it is very important to measure the water content of crude oil in real time. The receiving and transmitting helical antenna was designed for a measurement system about water content in crude oil according to the basic principles of helical antenna. The return loss（S,,） of the antenna was less than -10 dB worked between 2～3 GHz. The transmission loss（S_（12）） was -11.3 dB in 2.45 GHz, and the simulation gain is 11.4 dB. In order to improve the test accuracy, a conical metal shielding of antenna was desiged, and the simulation results meet the requirements. Further, three types of helical antennas were fabricated according to the simulation parameters. The test results show that the S_（11）meets the engineering requirements within the bandwidth. And the S_（12） is measured for arbitrary two antennas,and S_（12） of the two antennas is 12. 1 dB when the distance is 150 mm, which reaches the system design target.