Design and Comparison of Modified Circular Bow-Tie Antenna for Under Water Radio Communication by Optimizing Different Parameter

Abstract

Underwater communication systems have received much attention in recent years. For underwater communication it requires specific techniques and devices which give totally different criteria as compared to the air. In the ocean salts water provide a hindrance for electromagnetic radiation such as normal radio communication because salt water acts as thick conductors. To successfully develop radio wave based communication solutions, antenna becomes an important element regarding the propagation aspects of the electromagnetic waves in liquid. To meet a particular design goal, one possible approach is to study the parameter and geometric configuration of antennas. Design, simulation and measurement of circular bow-tie antenna, a conventional and modified circular bow-tie antenna are reported in this thesis. The five different parameters (Height, Thickness, Width, Angle and Feeding) of antenna are optimized and analyzed. The software simulation result obtained by study of various parameters for antenna and shows the acceptable characteristics. The return losses and radiation patterns of the antennas are simulated with CST Microwave Studio and the results are compared with measurements, the comparisons show that there is an excellent agreement between the simulations and measurements for different cases. Furthermore, the radiation performance of the modified circular bow-tie antenna is verified, by simulations and measurements. Low operating frequency, small size, ultra-wide band property and low level return-loss make the efficient candidates for excellent alternative to other antenna system used in under water radio communication. The behavior of the antennas determines the electromagnetic wave propagation in water. In addition, it is also verified that the behavior of the designed antenna will lead to a reduction in return-loss resulting improvements in radiation pattern and overall antenna efficiency.