Developing Polarimetric GPR System
Most ground penetrating radar (GPR) transmits and receives radio waves with a single polarization. That is, they measure the reflected power returned from the radars horizontal pulses or vertical pulses. Polarimetric GPR measure the reflected power returned from both horizontal and vertical pulses. By comparing these reflected power returns in different ways (ratios, correlations, etc.), we are possibly to enhance signal and obtain more information on the size, shape, and physical property, etc. We are developing a stepped-frequency (SF) polarimetric GPR system, which consists of two transmit antennas, two receive antennas, scanning platform, and vector network analyzer (VNA). VNA can generate ultra-wideband electromagnetic signal. Vivaldi antennas are employed in this system, because it is a kind of microstrip antenna, which possesses a wide bandwidth and a high cross-polarization ratio. Four antennas are oriented downwards to the ground and are organized into a tetrahedral square. The measurement method is to alternate between horizontal and vertical polarizations with each successive pulse. That is, first horizontal, then vertical, then horizontal, then vertical, etc. And, of course, after each transmitted pulse there is a short listening period during which the GPR receives both reflected horizontal and vertical polarization radio wave pulses. We test the polarimetric performance of the GPR system using both copper plate reflector and copper trihedral corner reflector. When the reflector is the copper plate, strong co-polarimetric (V V polarimetric and HH polarimetric) signals are detected and very weak cross-polarimetric (HV polarimetric and V H polarimetric) signals are detected. When the reflector is the copper trihedral corner reflector, strong cross-polarimetric signals are detected.
Xuan Feng Li-Li Li Li-Min Liu Cai Liu
College of Geo-Exploration Science and Technology,Jilin University No.6 Xi Minzhu Street,Changchun 1 College of Instrumentation and Electrical Engineering No.6 Xi Minzhu Street,Changchun 130026,China
国际会议
Progress in Electromagnetics Research Symposium 2009(2009年电磁学研究新进展学术研讨会)(PIERS 2009)
北京
英文
800-803
2009-03-23（万方平台首次上网日期，不代表论文的发表时间）