A flexible microstrip patch antenna is fabricated and studied in the X-band frequency range using linear low-density polyethylene and silica-doped barium titanate polymer-nano-composite substrate. A standard solid-state approach is used to synthesize silica-doped barium titanate nano-ceramics. Powder X-ray diffraction, Fourier transform infrared spectroscopy, and transmission electron microscopy are used to confirm the structure and morphology of the nanomaterials. For dielectric studies, composite substrates are developed by homogeneous dispersion of the nano-inclusion in LLDPE matrix in three different wt%. The scanning electron microscope is used to verify the homogeneous distribution of nano-inclusion in the host polymer matrix. Different types of physical characteristics such as water absorption, density, thermal conductivity, and thermal expansion coefficient are measured and calculated by following standard ASTM procedure. The developed nano-composite is characterized by its X-band dielectric properties by the Nicolson-Ross method, which confirms its utility as a microstrip patch antenna substrate. The composites' real part of permittivity and dielectric loss tangent is in the range of 2.25-2.5 and 10-2-10-4, respectively. The transmission line model is used to fabricate a microstrip patch antenna at 9.8 GHz by using the 6% optimally filled composite. The fabricated antenna shows S11 and % - 10 dB bandwidth of - 31.85 dB and 6.13%, respectively, for a flat profile.
