Slot Loaded Offset Feed SIW Cavity Backed Triangular Perturbed Antenna with Improved Bandwidth

This article describes a new technique for enhancing the bandwidth of substrate-integrated waveguide (SIW) cavity-supported slot antennas with symmetrical triangular perturbed cavities. One way the cavity-backed antenna feeding method has been modified is by employing offset feeding of a microstrip line and a transition from the microstrip to the grounded coplanar waveguide. This helps to excite the TE120 mode in the cavity while increasing the impedance matching to the slot antenna. The proposed antenna has a resonant frequency of 10.4 GHz, a bandwidth of 4.3%, a gain of 5.54 dBi, a front-to-back ratio of 10.6 dB, and a maximum cross-polarization level of −30 dB. It is designed to operate in the X band (8–12 GHz) applications.