A Directional Antenna in a Matching Liquid for Microwave Radar Imaging

Abstract

The detailed design equations and antenna parameters for a directional antenna for breast imaging are presented in this paper. The antenna was designed so that it could be immersed in canola oil to achieve efficient coupling of the electromagnetic energy to the breast tissue. Ridges were used in the horn antenna to increase the operating bandwidth. The antenna has an exponentially tapered section for impedance matching. The double-ridged horn antenna has a wideband performance from 1.5 GHz to 5 GHz (3.75 GHz or 110% of impedance bandwidth), which is suitable for breast microwave radar imaging. The fabricated antenna was tested and compared with simulated results, and similar bandwidths were obtained. Experiments were conducted on breast phantoms using these antennas, to detect a simulated breast lesion. The reconstructed image from the experiments shows distinguishable tumor responses indicating promising results for successful breast cancer detection.

3-D Printed UWB Microwave Bodyscope for Biomedical Measurements

“…A technique to achieve both compactness and matching is immersing antennas in a high permittivity media, thus reducing its dimensions and improving the matching between the radiator and the biological target [6]. High permittivity materials such as water [7], [8] or canola oil [9] have been proposed as immersive matching liquids. However, using liquids inside plastic or glass containers increases the overall volume of the measurement setup and difficults maintaining regular clinical sanitation of the liquid.…”

A 3D-Printed High-Dielectric Filled Elliptical Double-Ridged Horn Antenna for Biomedical Monitoring Applications

“…Different dielectric liquids and their mixtures with highpermittivity and low-conductivity materials have led to the conclusion that a particular type of oil, e.g. canola oil, is of interest due to its low-conductivity, low-cost, and safety for skin-based biomedical monitoring systems [20]. However, using a liquid for a biomedical system is not optimal, and hence, the better solution of solid material, such as paraffin was used.…”

“…The developed mixed material is selected as the background material in the simulation software to evaluate the antenna performance inside the dielectric medium based on the real data. The usual sufficient energy −6 dB point was used here to satisfy the general biomedical application [20]. In addition, the higher energy (i.e.…”

Optimization of Multi-Band Characteristics in Fan-Stub Shaped Patch Antenna for LTE (CBRS) and WLAN Bands

“…Novel structured UWB antennas with S 11 less than -20 dB have been also proposed to cover the 5.2/5.8 GHz WLAN system [19][20], but their multistage recumbent structure and configuration brings complexity in its fabrication steps. Historically, materials with the low dielectric constant ( ) such as different classes of Rogers material have been in extensive use as an antenna's substrate [21][22] for all kinds of telecommunication antennas except biomedical applications based antennas [23][24][25][26][27][28].…”