Optimization and integration of high‐performance ground penetrating imaging radar system: A research prototype

Abstract

This paper reports the design, development, and field experimentation of a new ground penetrating imaging radar system. This research prototype unit features full system optimization, which successfully integrates the key components of antenna sensitivity, data-acquisition waveforms, synthetic-aperture scan, and image reconstruction algorithms, for optimal system performance. Key words: ground penetrating imaging radar; Vivaldi antennas; FMCW waveforms; synthetic aperture imaging; backward propagation method I. INTRODUCTION Ground penetrating radar (GPR) has been playing an increasingly important role in many applications in nondestructive evaluation (NDE) and subsurface profiling. Common applications include locating and identifying utility supply lines, monitoring environmental sites, assisting archaeological and forensic investigation, surveying surface transportation infrastructure, and detecting structural voids, cavities, and deterioration (Mast et al., 1990;1994;Koppenjan and Bashforth, 1993;Warhus, 1993;Lockwood and Lee, 1997;Koppenjan et al., 2000). At UC Santa Barbara, significant research has been conducted over the past 15 years to advance the tomographic imaging capability of the GPR systems. More recently, system integration has been further enhanced for optimal overall system performance.A high-performance GPR imaging system consists of four key modules: (1) high-efficiency antennas, (2) wideband illumination waveforms, (3) high-precision synthetic-aperture scan, and (4) highresolution image reconstruction algorithms. To optimize the performance and precision of wave propagation, Vivaldi antennas are selected for improved sensitivity. Spatially-coded scanning scheme is implemented to improve the accuracy of positioning of the dataacquisition process. The high-resolution image reconstruction is achieved by using wideband step-frequency FMCW waveforms for