In this study, a new approach for the design of microstrip antenna is proposed. The resonant frequency of the proposed antenna is 3.55 GHz allowing it to operate in the mobile network current 5G band (the mid band). The design approach is based on a wedge shaped substrate having relative low thickness at the level of the feed line and a higher thickness at the level of the radiating patch. The FR4 wedge substrate based design of 6 mm linear slope enhance the radiation by 9% and the bandwidth by 10.3 % while degrading the return loss by 2.3 dB with respect to a standard box substrate based antenna design of the same dimensions. To remedy the degradation in terms of S11, the rectangular inset feed line is replaced by a trapezium one which re-enhance the return loss by 3.4 dB and then making it better than the original one.