Compact Slotted Microwave Antennas with Harmonics Suppression for Mobile and WLAN Applications

This paper presents three compact slotted microwave antennas with lower and higher-order harmonics suppression for mobile and wireless local area network (WLAN) applications. The antennas possess simple designs of symmetrical structures with novel geometrical slots for a stable bi-directional radiation, better impedance matching, and acceptable gains. The antenna prototypes were fabricated and tested in order to validate the simulation results of reflection coefficient, gain, and radiation patterns. The antennas measured results show that an impedance matching (|S
11
|) of less than -20 dB, realized gains of 2.4 dB, 2.1 dB, and 2.8 dB obtained at 0.99 GHz, 2.08 GHz and 5.15 GHz resonance frequencies. These antennas are can be good candidates for mobile and WLAN applications that need suppressing the unwanted higher-order frequencies and also for wireless power transfer applications.