Frequency Reconfigurable Antenna for Multi Standard Wireless and Mobile Communication Systems

In this paper, low profile frequency reconfigurable monopole antenna is designed on FR-4 substrate with a compact size of 30 mm3 × 20 mm3 × 1.6 mm3. The antenna is tuned to four different modes through three pin diode switches. In Mode 1 (SW1 to SW3 = OFF), antenna covers a wideband of 3.15–8.51 GHz. For Mode 2 (SW1 = ON, SW2 to SW3 = OFF), the proposed antenna resonates at 3.5 GHz. The antenna shows dual band behavior and covers 2.6 and 6.4 GHz in Mode 3 (SW1 and SW2 = ON, SW3 = OFF). The same antenna covers three different bands of 2.1, 5 and 6.4 GHz when operating in Mode 4 (SW1 to SW3 = ON). The proposed antenna has good radiation efficiency ranges from 70%∼84%, providing adequate average gain of 2.05 dBi in mode 1, 1.87 dBi in mode 2, 1.4–1.75 dBi in mode 3 and 1.05–1.56 dBi in mode 4. The achieved impedance bandwidths at respective frequencies ranges from 240 to 5000 MHz. The Voltage Standing Waves Ratio (VSWR) of less than 1.5 is achieved for all operating bands. To validate the simulation results, the proposed antenna is fabricated and experimentally tested in antenna measurement laboratory. Due to its reasonably small size and support of multiple bands operation, the proposed antenna can be used in modern communication systems for supporting various applications such as fifth generation (5G) mobile and wireless local area networks (WLAN).