Ultrawideband Antipodal Vivaldi Antenna for Road Surface Scanner Based on Inverse Scattering

High quality inverse scattering based scanner for pavement nondestructive testing needs a high performance antenna with certain characteristics. This paper considers an UWB antipodal Vivaldi antenna for this application. Simulation results for the targeted frequency range obtained through the use of Sonnet modeling software show that this antenna is characterized by a good match over the broad frequency range as well as a frequency dependent gain. The antenna performance has also been analyzed in the near field by considering tangential electric fields in the close proximity of the radiating structure. The antenna described in this paper is a part of a larger research project with a goal to develop a scanning device based on inverse scattering methods and used for accurate, non-destructive, and inexpensive characterization of road pavements. The system will use a state-of-the-art, fast and accurate numerical solver for 3D inverse scattering problems in stratified media. The solver will utilize as input the measurement data provided by the antenna scanner to reconstruct several properties of the paved structure under test. The pavement under test will be illuminated by a number of transmitting antennas, and the scattered field collected by receiving antennas in the measurement plane. The scanning system will measure the amplitude and phase of the scattered electric and magnetic field vectors at the receiving antennas, at a set of discrete frequencies in the microwave range. Both monostatic and bistatic measurement configurations will be considered (1).