This article implements the high gain superstrate antenna and wideband bandpass microwave filter using a novel uniplanar compact Electromagnetic Bandgap (EBG) structure. The proposed EBG unitcell consists of an outer inductive grid connected to four square loops at corners separated by a center-spitted Jerusalem cross resembled dipole. The design is printed on top of a 0.8 thin Rogers RT Duroid 5880 grounded dielectric substrate. Wide bandgap behavior is observed in the intended EBG from 9.6 GHz to 12 GHz (22.22% FBW). Here, the two different applications of the proposed EBG are presented, which gain the main focus of this work, i.e., EBG loaded microstrip filter and an EBG superstrate for a microstrip patch antenna (MPA) gain enhancement. The unitcell performance is stable for different oblique incidences under Transverse Electric (TE) and Transverse Magnetic (TM) modes. Compared to the reference antenna, the EBG-loaded patch exhibits a gain improvement, and 10.95 dBi is achieved along with bandwidth improvement. The C-band is the intended operating range of a proposed EBG-based wideband filter having less than 1.05 dB Insertion Loss (IL) over the operational range 5.26-13.32 GHz or 86.86%, and its passband BW covers from 5.30 - 13.71 GHz (88.48%). © 2022 IEEE.