Magnetodielectric substrate gives a new dimension for reducing the size of the planar antennas. In this article, the patch size is reduced by taking a substrate with nano-sized nickel ferrite inclusions in LDPE polymer matrix. The antenna is made to operate in X- and Ku-bands by engraving T slots along the resonant length of the patch. Structural modification of the substrate geometry as a step profile is incorporated along the slotted patch edges to enhance performance. The T-slots, on both the radiating edges with the magnetodielectric stepped substrate show four resonant frequencies in both the X- and Ku-bands with S11 < -15 dB and a maximum -10 dB bandwidth of 22.4%. A miniaturization factor of 2.97 is obtained.
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