In this paper, a conventional mushroom-type EBGunit cell is made compact by etching a C-slot at its conductingsurface. Further, the C-slotted mushroom-type EBG unit cell iscoupled with a microstrip line using a novel groove-couplingtechnique to design a notch filter. The arrangement has achievedin the reduction of the electrical size of the mushroom type EBGunit cell by 46.15% and create a stop band suppression of -12 dB.The proposed EBG is applied to notch a narrow band centeredat 5.2 GHz along with an ultra-wideband antenna. The far fieldgain of the antenna is suppressed by- 5.8 dBi along the directionof its major lobe at 5.2 GHz. The overall size of the antennasystem is 19×27×1.6mm3 which is compact. The performanceof the antenna is validated from the simulation and measuredresults
