A substrate integrated waveguide (SIW) fed rectangular-shaped dielectric resonator antenna (DRA) is proposed for application in the D - Band frequency regime. The Dielectric Resonator (DR) designed to operate higher order modes. narrow slot used excite DR element, leading multiple resonances. resulting structure a multi-resonant operating at six frequencies 123.64 GHz, 125.76 127.4 129.9 134.9 ...