A Broadband Pyramidal Horn Antenna Applied to Multi-mode Multiplexing

A new design of a broadband pyramidal horn antenna is realized, which can be applied to multi-mode multiplexing. To achieve the purpose of multimode radiation, a four-port coaxial-line adaptor has been designed to allow for the transmission of signals of required modes TE
10
, TE
01
, TEn and TM
11
). In addition, two circularly polarized waves with different rotation directions can be obtained by combining TE
10
and TE
01
on this basis. By controlling the amplitudes and phases of the signals from four feeding ports, the distribution of the fields in the waveguide will also be changed accordingly. The waveguide modes will be converted into radiation modes through the horn face. As a result, six different radiation patterns are acquired. The simulated results show that the simulated 10 dB return loss bandwidth is approximately 31.6% (ranging from 10.25 to 14.09 GHz, center frequency is 12. 17GHz), and the isolation is less than -20dB. The return loss coefficients of the six different modes also meet the requirements (less than -10dB) between 10.86 and 13.64 GHz.