This work investigates improving dielectric resonator antenna (DRA) radiation bandwidth through the integration of linearly graded permittivity profiles. Using Characteristic Mode Analysis (CMA), it is shown that such profiles broaden modal distribution, consequently extending the bandwidth of the dominant resonant mode. The proposed antenna design is enabled by additive manufacturing techniques, which allow precise control over material composition and geometry. Experimental results show a significant improvement in both modal and impedance bandwidth from 9.1% to 24,1%, leading to a more stable gain across the operating frequency range.