Experiments with a dipole array and loop antenna in a cylindrical water layer
Experiments with a dipole array and loop antenna in a cylindrical water layer
复制标题
圆柱形水层中偶极子阵列和环形天线的实验
DOI：
10.1109/icgpr.2016.7572659
复制
发表时间：
2016
期刊：
影响因子：
--
通讯作者：
G. Hoshii
中科院分区：
文献类型：
--
作者：
S. Ebihara;Y. Shimomura;K. Hotta;K. Hosokawa;G. Hoshii
本文介绍了地下测量使用单孔定向钻孔雷达系统，揭示了一种导波传播的存在，沿沿着钻孔。该雷达系统的发射机和接收机均采用偶极子阵列。在这种情况下，所有天线元件都位于钻孔中心轴之外。计算机模拟证实，偏离中心的偶极子将激发高于约200 MHz的HE11模式。该模式的特点是阵列信号之间存在较大的相位差，时域波形呈阻尼振荡波形。为了测试这些预测，钻孔雷达系统的设计和建造与偶极子阵列和环形天线的发射器和接收器，该系统用于土壤中的现场实验。我们观察到的HE11模式波在200 MHz以上的频率，在模拟中预测。当中心频率为100 MHz时，在实验数据中的时域中没有阻尼振荡波，并且我们确认不存在导波，正如计算机模拟所预期的那样。
This paper describes subsurface measurements using a singlehole directional borehole radar system that revealed the presence of a kind of guided wave propagating along the borehole. The radar system used dipole arrays for both the transmitter and receiver. In this case, all the antenna elements were located off the center axis of the borehole. Computer simulations confirmed that the off-center dipole would excite the HE11 mode above about 200 MHz. The characteristics of the mode are that there is much phase difference among the array signals, and waveforms in the time domain are shaped like a damped oscillatory wave. To test these predictions, a borehole radar system was designed and built with a dipole array and a loop antenna for both the transmitter and receiver; the system was used for field experiments in soil. We observed the HE11 mode waves at frequencies above 200 MHz, as predicted in the simulation. When the center frequency was 100 MHz, there was no damped oscillatory wave in the time domain in the experimental data, and we confirmed that there was no guided wave, as expected from the computer simulation.