This work presents the design and simulation of a dual band rectangular patch antenna operating at 2.4 GHZ, and 3.5 GHZ for Zigbee and Wimax applications. The proposed antenna is expected to meet the requirements of wireless connections in the architecture of a pre-hospital emergency system inspired from the literature, which uses the Internet of Things (IOT) technology. The simulations were carried out under the High Frequency Electromagnetic Field Simulation (HFSS) simulator, and validated by Computer Simulation Technology (CST) software.