Adaptive wire bow-tie antenna for GPR applications

Abstract

Abstract-In this paper, the basic design of an adaptive ground penetrating radar antenna is introduced. The antenna is able to adapt its input impedance to a variation in the antenna elevation and soil type to keep reflections at the antenna's terminal minimum. As a result, energy transfer from the generator to the antenna is maximized, which in turn maximizes the energy radiated by the antenna into the ground for different antenna elevations and soil types. The antenna is based on a wire bow-tie structure with variable flare angle for adjusting the antenna's input impedance. The flare angle variation is realized by short-circuiting the gaps separating the wires from the feed point of the antenna, for which electronic switching devices such as PIN diodes could be used to allow fast and convenient control of the antenna's flare angle.

Wideband Antennas for Modern Radar Systems

“…When the maximum power transferring from the transmitter to the antenna, via a transmission line, is considered critical, one should provide a variable matching device which is capable of coping with such impedance variation to achieve a matched termination of the antenna for different antenna elevations and ground types. The new design of the GPR antenna allows such a fast and convenient way for controlling the bow-tie flare angle required in a real GPR survey, while the antenna could promptly adapt to any changes in antenna elevation and soil type, as shown in Figure 14 (Lestari et al, 2005).…”

Patch antennas with superstrates for landmine detection

“…A good GPR antenna is required to have a wide band width [3], small size [4], high directivity [5] and good matching. As a result, different antenna types have been employed in GPR systems including bow-tie antenna, and resistively loaded vee dipoles [6]- [8].…”

Wideband Loaded Wire Bow-tie Antenna for Near Field Imaging Using Genetic Algorithms

“…Drastic improvement is later been made by [2] by representing the typical solid bow tie antenna with a series of wires by means of Genetic Algorithm (GA). The Wire Bow-Tie (WBT) antenna is found more adaptive and advantageous as it is easily loaded with lumped elements to accommodate certain applications need while preserve its characteristics [3,4]. Further improvement has also been done by the same group by resistively loading the design to minimize late-time ringing.…”