Design of a Cloverleaf Shaped Wideband Antenna for 5.8 GHz Wireless Application

This paper presents a novel wideband dualpolarized PCB antenna excited by a square ring structure. The proposed design operates in the frequency range of 5.8 GHz (5725 - 5850 MHz) and is composed of cloverleaf-shaped symmetrical dipoles, microstrip lines, square ring structures, copper cylinders, coaxial cables and a copper reflector. The dipoles, microstrip lines, and square structures are printed on a PCB substrate (FR4). The square ring structure feeds the dipoles through electromagnetic coupling with the microstrip lines. When the Voltage Standing Wave Ratio (VSWR) is less than 2:1, the design offers an impedance bandwidth of 54.6% (4.32 to 7.49 GHz). Both ports exhibit the S-parameter of S11 at -21.9 dB at 5.8 GHz, corresponding to a VSWR of 1.17. The simulated and measured gain is approximately 9.4 dBi, with an isolation level (S21) below -25 dB at 5.8 GHz. Furthermore, the overall antenna architecture is simple and suitable for point-to-point or point-tomultipoint communication systems, high-speed wireless LANs, and Bluetooth technology devices.