The performance of microstrip antenna arrays is greatly undermined by the excitation of spacernwaves and surface waves which cause mutual coupling between microstrip antenna elements.rnMutual coupling between antenna elements can affect the side lobe levels, beam position andrnfrequency bandwidth of arrays. Mutual coupling through space waves are very strong if the arrayrnelements are very close to each other, and they can be suppressed by increasing the interelementrnspacing between the array elements. Defected ground structure (DGS) is a type of metamaterialsrndesigned at ground that is used to minimize the surface wave and prevents the degrading inrnperformance of an antenna. Frequency Selective Surface (FSS) is also useful in miniaturizationrnof a designed antenna.rnIn this thesis work, a ground plane is loaded with defected ground structure and frequencyrnselective surface techniques to minimize the effect of coupling loss and to enhance thernperformance of the MSPA.rnA rectangular-aperture coupled microstrip patch antenna is first designed for S-band applicationrnand 2x1 MSPA antenna array is formed by using the optimized design of the individual antennarnfor an inter element spacing l/4 (where l is the operating wave length of the antenna which isrnequal to 130.43mm). Then a simulation is carried out to measure the S11, S12, and otherrnparameters of the antenna. Finally, DGS &FSS are applied on the antenna and the reduction inrncoupling loss is analyzed using HFSS Software.rnThe result of the study indicates, 2X1 rectangular micro strip patch antenna array inserting FSSrnat the ground plane were proposed for 2.3GHz which has an improved bandwidth ofrn71.8MHzand mutual coupling effect is -35.668dB when compared with an antenna array withrnDGS.