In the wireless communication applications, widespread usage of microstrip patch antennas  due to their advantages such as compactness, easy fabrication and low cost, is pushed forward researchers to develop desired antennas or improve the existing antennas to get desired one. But it is challenging to get desired antennas since microstrip patch antennas have some disadvantages such as low gain and narrow bandwidth.  In this work, elliptical patch microstrip antenna is designed for Bluetooth/Wi-Fi applications. The antenna is designed in the form of slotted elliptical patch and defected ground structure method. Defected ground structure method is applied by using rectangular slots with different dimensions in this work. The proposed antenna is modelled using CST MWS software. Return loss, gain and directivity values are -16.45 dB, 1.82 dBi, and 5.81 dBi at 2.45 GHz, respectively. On the other hand, maximum directivity and gain values are 5.86 dBi and 2.06 dBi at 2.4 GHz, respectively. The bandwidth is 63.1 MHz (2.41 GHz – 2.48 GHz) at 2.45 GHz. According to the results, IEEE 802.11 b/g standards are supported by the designed antenna. So, it can be used for Bluetooth and Wi-Fi applications at 2.4 GHz.

In recent years, according to the requirements of wireless applications, multiband and low profile patch antennas are desired. In this study, a simple rectangular patch triband microstrip antenna is developed to use for Bluetooth/WiFi applications. The antenna is in the form of rectangular slots with different lengths loaded on the rectangular patch with reduced ground size. FR-4 substrate with 1.6 mm thickness is used as substrate material and annealed copper is used as ground and patch materials. The designed antenna is simulated using CST MWS software program. Microstrip line feeding technique with discrete port is used to feed the antenna. According to the results, S11 parameters of three resonant frequencies can be given as  -15.08 dB, -11.88 dB and -24.03 dB at 2.39 GHz, 3.07 GHz and 4.92 GHz respectively. Gain values of the resonance frequencies can be given as follows, 2.25 dBi, 3.76 dBi and 1.92 dBi at 2.39 GHz, 3.07 GHz and 4.92 GHz respectively. Proposed antenna bandwidth can be given as, 197.5 MHz (2.29 GHz – 2.49 GHz) at 2.39 GHz, 116.1 MHz (3.01 GHz – 3.13 GHz) at 3.07 GHz and 266.2 MHz (4.79 GHz – 5.06 GHz) at 4.92 GHz, respectively. Since the designed antenna can work at 2.4 GHz and 5 GHz frequency bands with 2.24 dBi and 2.34 dBi, respectively, IEEE 802.11ac/b/g standards are supported by the antenna. So the proposed antenna can be used for Bluetooth and 2.4 GHz/5GHz WiFi applications.