A miniaturized dual mode CRLH unit cell loaded SIW antenna

A dual-mode substrate integrated waveguide (SIW) antenna, based on composite right/left handed (CRLH) unit cell, is proposed in this paper. The CRLH unit cell is a designed by etching an interdigital capacitor (IDC) slot on the top plane along with a circular complimentary split ring resonator (CSRR) on the ground plane. Due to application of CRLH unit cell, zeroth order resonance (ZOR) is obtained at 1.95 GHz along with the conventional first order resonance mode. Analytical and parametric studies show that the electrical size of the antenna can be effectively reduced by increasing the width of the complimentary split rings. Compared to other SIW-IDC antenna, the present design has a smaller cavity size of 0.13λ₀×0.13λ₀ at lowest resonant frequency. For n=1 mode resonant frequency, a significantly high gain of 5.97 dBi is obtained at 5.65 GHz.