Design and Performance Evaluation of Axial Mode Helical Antenna in Cylindrical Water Pipe Network Having Irregular Internal Depositions

This paper reports design of axial mode helical antenna and its performance evaluation in cylindrical water pipe network under the condition of completely filled with water, partially filled, empty and water mixed with sand deposition. Impedance matching has been achieved by using back-to-back tapered line transition. This enhances the mechanical stability of the designed helical antenna and also increases directivity in comparison with other antennas reported for underwater applications. The gain and directivity of the designed helical antenna (completely water-filled pipe) obtained using full-wave e. m. solver CST Microwave studio are: −20.7dB and 7.21dBi respectively.