FDTD investigation of end effect and multislot effect on the circumferentially slotted coaxial antenna

Abstract

The finite‐difference time‐domain method (FDTD) is first applied to investigate the reflection and radiation properties of a finitely long coaxial antenna with circumferential slots on its outer surface. The end effect and multislot effect intractable for the moment method and mode‐matching method are analyzed efficiently and demonstrated in detail. According to the accurate analysis, the circumferential slots have a strong influence on the characteristics of the antenna. This effect can be used to effectively adjust the impedance matching and radiation pattern of the antenna. The verification of the method is also presented by reference to the experiment and the literature. ©1999 John Wiley & Sons, Inc. Microwave Opt Technol Lett 21: 35–39, 1999.