Studies on Slot Coupled Junction Radiator using S-Band Wave Guides

Abstract

In all radar and communication applications antennas plays an important role, for transmitting and receiving purpose. For certain special applications, it is required to have specifications like polarization, impedance, VSWR and radiation pattern characteristics. In H-Plane Tee junctions, the Tee arm is commonly coupled to the main wave guide by a longitudinal slot. However, the coupling can be done by inclined slot in the narrow wall of main wave guide. This structure acts as a radiator to produce vertically polarized waves. The knowledge of admittance characteristics of this new coupling system provides additional design parameters for the array designer. In the present work, the analysis is made to obtain variation of conductance, susceptance, coupling and VSWR as a function of frequency after determining the resonant slot length of S- band H-plane Tee junction wave guide. The results are numerically obtained for varied slot width and slot inclinations. The concepts of self-reaction and discontinuity in modal currents of the main guide as well as Tee arm are used in the analysis. The data presented are extremely useful for the design of small and large arrays of S band H-Plane Tee junction radiators,useful for near and far range weather observation like National Weather Service (NWS).