Abstract

In this paper, the design and analysis of microstrip-fed low-profile, compact ultra-wideband (UWB) monopole antenna with its multiple-input multiple-output (MIMO) configurations and two band-notches characteristics are carried out. The antennas are mounted on a low cost FR-4 substrate of dielectric constant 4.4. The original shape of the single antenna element is circular with radius of 11.5 mm, and then a sector is removed from the patch (making it a Pacman-shaped antenna) to improve the impedance bandwidth. The proposed antennas provide an impedance bandwidth between 2.9-15 GHz with better than 10 dB return loss and isolation less than -16 dB and -19 dB for the first and the second MIMO configurations, respectively. Additionally, the antennas can reject the interferences from WiMAX (3.5 GHz center frequency) and WLAN (5.5 GHz center frequency).

Key words: ULTRA WIDEBAND (UWB) ANTENNAS; CIRCULAR MONOPOLE ANTENNA; MULTIPLE-INPUT MULTIPLE-OUTPUT (MIMO)