Transmitter/Receiver Pulse-Driven Antenna Arrav with Near Field Beam-Forming for UWB Subsurface Imaging Radar
Abstract: The paper is devoted to design of impulse or equivalent ultra-wide baud array antenna for subsurface radar system. Receiving elements of this autenna are arranged in array with small physical aperture and polarimetric features. Two transmitting element support two polarization states for radiating signals. The radar antenna provides down-looking scanning in subsurface medium for small areas covered by array aperture and big areas due to synthetic aperture processing when array moves in 2-D plane along scanning lines. Operation in proximity to a rough dielectric interface affects significantly on radar operation. This and other factors are involved in array antenna design to get enough 3-D spatial scanning with the maximum resolution and range for the available bandwidth. Results of such array analysis, numerical simulation and experiments are presented and discussed.
Subsurface radar or ground-penetrating radar (GPR) technique is widely applied as a powerful technology of remote sensing and microwave imaging in many fields of science and engineering [6,7]. Among different schemes of building of GPR systems there are two dominant ones. The first schema is impulse or equivalent ultra-wide band (UWB) radar that operates in time-domain (TD). The second one involves stepped frequency or synthetic-pulse GPR and operates in frequency-domain (FD). The both radar have some mutually excepting benefits and drawbacks as well as different design approaches to radar antennas . Relative simplicity and inexpensive way of TD-GPR implementation are practically preferable for some applications. Due to this reason the UWB array antenna for TD schema of GPR is a subject of the presented study.