PURPOSE: To distribute the power with arranged phase to each radiation waveguide and to attain miniaturization by adopting stereoscopic multilayer structure that a feeding waveguide is arranged to the opposite side of the radiation face of the radiation waveguide and adopting the 2-distribution system for the feeding to 2n radiation waveguides.
CONSTITUTION: Feeding waveguides 6, 7 are provided to the lower part of the radiation waveguides 4, 5. Thus, number of radiation slots to the antenna area is increased to miniaturize the antenna or to increase the gain per area. Further, the length (waveguide length) of the feeding waveguide reaching the radiation waveguides 4, 5 from the feeding part 8 of the antenna is made equal by adopting the 2-distribution waveguide system repeating 2-distribution and the input power at the radiation waveguide input terminal is uniformized. Since the incident phase is shifted correctly by 180°, the disturbance of the electromagnetic field in the radiation waveguides 4, 5 is decreased by shifting the arrangement of the radiation element (slot) by λg/2 (λg is guide wavelength), a uniform electromagnetic wave with small phase disturbance is radiated from each radiation element to obtain an excellent circularly polarized wave.
OGA MASATOSHI
YAMAMOTO AKIO
SHINKAWA TAKAO
HITACHI VIDEO ENG
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