Analysis of the radiation from multiple slots on a conducting circular cylinder using the fourier transform and mode matching method

Abstract

Boundary-value problems of radiation from multiple slots on a conducting circular cylinder are solved rigorously using the approach of Fourier transform and mode matching method. The theoretical analysis is performed using the electric and magnetic vector potentials for field representations. The scattered fields are represented in terms of discrete and continuous modes based on the eigen function expansion, and the Fourier transform. The boundary conditions are enforced to obtain a set of simultaneous equations for discrete modal coefficients. The radiation, transmission, and reflection characteristics are expressed in rapidly convergent series. Computation is performed to illustrate the radiation behavior in terms of aperture geometry or frequency. The X-band slot array antenna is designed and fabricated by using a coaxially fed monopole, slotted circular cylinder, and SMA termination load. Our theory of Fourier transform and mode matching agrees well with the measured radiation patterns at 8.5, 9,2, and 9.6 GHz. Our theoretical model for radiation from multiple slots is useful for the analysis and design of slot array antennas using a conducting circular cylinder with a finite thickness.