Two-dimensional Polarity Orthogonal Multiplexing Antenna System for Non-far Region Communication

This paper presents an orthogonal multiplexing antenna system for non-far region communication, which is based on two-dimensional polarity in the rectangular coordinate system. In other words, it is based on two-fold symmetry and anti-symmetry between the transmission modes. The twodimensional polarity comes from the structural symmetry of magic-T components used in the corporate-feed circuit in the antenna in the millimeter-wave band. The structural symmetry gives wideband operation. The feasibility is shown by a system where a corporate-feed waveguide slot array antenna and a monopulse circuit are combined. 4-multiplexing 40cmtransmission using 16x16-slot arrays are confirmed by experiments in the 80GHz band. The transmission enhancement is also shown by optimizing the excitation in the slot array for a given distance and by the dual polarization use.