Sum and Difference Beams Antenna Based on Odd-Even Mode Composite Waveguide

A novel sum and difference beams antenna is proposed, which based on odd-even mode composite waveguide. The in-phase electromagnetic field is realized by exciting the even mode of spoof surface plasmon polariton (SSPP), and the out-of-phase electromagnetic field is realized by exciting the even mode. They transmit at the same frequency band. In this design, a gradient vivaldi-shaped flaring structure achieves sum and difference beams in the endfire direction. The transmission characteristics are given and analyzed. The simulated results show that the sum and difference beams antenna can operate from 10.5 GHz to 14.5 GHz. The sum beam realized gain is 11.9 dBi at 13 GHz, and the difference beam realized gain is 9.67 dBi at 13 GHz.