Microstrip patch antenna is very popular in communication applications for its compact size and low cost. The efficiency and bandwidth of these antennas are limited regardless of how they are used, and they must be enhanced. The simulation and design of a revolutionary miniaturized microstrip patch antenna with radiating double-slotted patch and a perfect value of voltage standing wave ratio (VSWR). This proposed antenna has a double band with operating frequency 2.41GHz and 3.27GHz, respectively, making it ideal for Satellite, RADAR, Wi-Fi, and ISM band applications. The ISM band 2.4–2.483GHz is also included in the S-band. This band is used for industrial, scientific, and medical applications. Using Computer Simulation Technology (CST), this research tries to improve the efficiency of a rectangular-double patch antenna. To achieve ideal antenna characteristics, various patch sizes and substrate materials are explored. After that, slot designs and double patches are included to improve the antenna performance even further.