K Sridevi, Dr. D. Akhila John 02 09 This work presents the performance of a Dualband patch antenna with Cshaped slot for biomedical applications The antenna works at 21 GHz and 24 GHz A substrate material which is FR4lossy with a relative dielectric constant r of 43 loss tangent tan of 0025 and thickness hs of 1524 mm has been proposed The size of the antenna is 130 x 80 mm The slots in the rectangular radiating patch were introduced to produce the resonant frequencies of 21GHz and 24GHz The simulations of the microstrip patch antenna shows the reflection coefficient S11 of 122dB and 4122 dB at 21 GHz and 24 GHz respectively The proposed antenna shows a peak gain of 062 dB at 24 GHz The results were obtained using CST studio Copyright (c) Journal of Engineering Technology and Sciences. All rights reserved 2026