A compact substrate‐integrated‐waveguide monopulse slot antenna array with TE20 mode

A compact substrate‐integrated‐waveguide (SIW) monopulse slot antenna array with TE20 mode is proposed, manufactured, and tested in this communication. The TE20 mode electric field distribution is used in this antenna design. The phase difference required by the monopulse system is constructed by changing the orientation of the end of the top microstrip feed line. The microstrip line implements not only the feed function, but also the function of a monopulse comparator. The design greatly reduces the size of the monopulse comparator and the feed network, and improves the aperture efficiency of the antenna. Our measurement shows that the operating frequency of the antenna is 10.4 GHz, and the maximum gain of the sum beam is 13.7 dBi, and the difference beam null depth is −26 dB. The antenna has the advantages of simple structure, small size, and easy integration of planar circuits. This proposed idea can open new ways for monopulse antenna design.