Search

A peach-like ultra-wideband (UWB) planar monopole antenna (PMA) with dual stopband characteristic is presented in this paper. It is designed to work on a substrate Rogers RT5880 that has a thickness of 1 mm and relative permittivity of 2.65. The proposed antenna is fed by microstrip line; the U-slot is used to reject the frequency band (3.3–4.2 GHz) limited by IEEE 802.11a or HIPERLAN/2. Another rejection band (5.15–5.825 GHz) limited by IEEE 802.11b and C-band satellite communication systems is obtained by using the V-slot defected ground structure (DGS). The size of the antenna is 33 mm × 35 mm. Effects of varying the interior degree of the V-slot DGS and the length of the U-slot on antenna performance have also been studied. Measured result shows the designed antenna with an impedance bandwidth covering at least 3.11 to 15 GHz assuming a 10 dB return loss, except 5.04–6.42 GHz and 3.35–4.24 GHz band. Also the simulated results show that the antenna has omnidirectional radiation patterns in the x-z plane and good gain flatness. [ABSTRACT FROM AUTHOR]

A coplanar waveguide (CPW) fed diamond monopole antenna with dual stopband characteristic is presented in this paper. The proposed antenna consists of a circular CPW feeding line and a diamond shape radiation patch. By using a U-slot in the feeding line, a stopband of 800 MHz for band rejection of wireless local area network (WLAN) is achieved. Another stopband of 600 MHz is obtained by implanting two slits in the ground plane. Experimental results show the designed antenna, with a compact size of 40 mm × 25.8 mm, has an impedance bandwidth of 3.2–10.7 GHz for voltage standing wave radio (VSWR) less than 2, except two frequency stopbands of 3.4–4.3 GHz and 5.1–5.9 GHz. Moreover, the antenna also shows omnidirectional radiation patterns in the H-lane and good gain flatness. [ABSTRACT FROM AUTHOR]