Recently, there are many studies of conformal antenna and cylindrical antenna problems. Conformal antennas make structure and antenna into one and excute as various communication ability. They are vary useful to airplane and sattlelite and so on. Cylindrical antennas are getting required for mobile telephon services as wideband width antenna. The study of radiation of a circumferential slot on a cunducting cylinder is the fundamental study of these antennas.
Until now this kind of study is analyzed various method like moment method and transmission line equation. These methods are numerical and approximation method. So we proposed another method. It`s a fourier transform and mode matching method. This method is very useful when the geometry of the structure is a juntion of two or more regions.
In the closed resions, we represent the fields as the sum of fourier series and in the opened regions, we repreent the fields as the fourier integrals. But these are all get from the maxwell equations. The radiation pattern and reflect coefficient when the incident wave is $TM_01$ and $TE_11$ are analyzed.
