Feasibility on multiplexing antenna system based on rectangular-coordinate orthogonality by using two-dimensional 180-degree hybrid

For mode multiplexing transmission using two-dimensional orthogonal field distribution, a beam switching circuit is designed and transmission between Tx and Rx antenna systems are calculated. Generation of orthogonal four modes by the beam switching circuit is presented in this paper. The simulated isolations between the orthogonal modes are over 20 dB at the center frequency.