Hybrid HMSIW Cavities Antenna With a Half-Pentagon Ring Slot for Bandwidth Enhancement

A substrate-integrated waveguide (SIW) antenna is an implementation of a in microstrip antenna. The antenna, as low-profile suffers from narrow impedance bandwidth. This paper proposes novel bandwidth enhancement method for solving Bandwidth was achieved by using quad-resonant frequencies. frequencies are resulted the hybrid half-mode (HMSIW) cavities between inner and outer cavities. HMSIW cavity has half-pentagon ring slot that disturbs TE $_{\mathrm {101-inner}}$ , {102-inner}}$ {202-inner}}$ {103-inner}}$ modes, whereas consists two quarter-mode (QMSIW) generated {102-outer}}$ {202-outer}}$ modes. were fed simultaneously port with quarter-wavelength feed transmission line. resonant close to each other. Additionally, this applied X-band frequency substrate. simulated peak realized gain 33.86% ( notation="LaTeX">$8.98-12.64$ GHz) 7.97 dBi, while measured 31.83% (9.14 – 12.6 7.62 respectively. Strong agreement observed measurement simulation results.