Design of a ‘U’ Slot Substrate-Integrated Waveguide Cavity-Backed Self-Diplexing Antenna

In this paper, the simple design of a "U" slot substrate-integrated waveguide (SIW)-based single substrate self-diplexing antenna is proposed. Two longitudinal slots (similar length) and one transverse slot are designated for "U" slot representation respectively, which radiate at two separate resonant frequencies, being imprinted on the top surface of the antenna. Two different microstrip feed lines are used to feed the SIW antenna. A high degree of isolation is achieved between the two ports.