In this chapter, a tri-band microstrip patch antenna for C, X, and Ku band applications has been designed. The antenna having the dimensions of 30 × 35 × 1.6 mm3 is simulated using CST Microwave Studio (Sharma et al, 12th international conference on microwaves, antenna, propagation and remote sensing, ICMARS, 2017) [1]. The microwave signal is supplied by microstrip transmission line. The minimum return loss (−40 to −52 dB) for each band is achieved by cuts at the corner and defective ground resulting in better VSWR. The antenna operates in five band f1 = 4.85 GHz (4.05–7.10 GHz), f2 = 10.04 GHz (9.05–12 GHz), f3 = 15.09 GHz (13.77–16 GHz) covering approximately entire C band (4–8 GHz), X band (8–12 GHz), and Ku band (12–18 GHz) (Sharma et al, 12th international conference on microwaves, antenna, propagation and remote sensing, ICMARS, 2017) [1] coming under microwave …