A compact microstrip-fed multiband planar antenna for global positioning system, worldwide interoperability for microwave access, and wireless local area network applications is presented. Three operating frequency bands are achieved by a pair of L-shaped slots and rectangular slots, and defected ground structure. The fabricated prototype for the proposed antenna occupies an area of 32 3 22.6 mm 2 . The measured results show that the proposed antenna has 10 dB impedance bandwidth of 420 MHz (1.34-1.76 GHz), 590 MHz (3.21-3.80 GHz), and 1.5 GHz (5.05-6.55 GHz). The proposed antenna shows good radiation patterns and acceptable gain over three operating bands.

A novel compact wideband and dual-band microstrip-fed antenna is proposed. By using symmetrical inverted-L-shaped strips, a forkshaped strip, a rectangular slot and a defected ground plane, the dual-band resonances of the antenna are generated. The measured impedance bandwidths are 1.12 GHz for the lower frequency band (1.87-2.99 GHz), and 780 MHz for the higher frequency band (5.10-5.88 GHz). The fabricated antenna can be used to cover the entire required bands for time-division-long-term evolution (1880-2655 MHz) and wireless local area network 802.11 a/b/g (2.4-2.4835, 5.15-5.875 GHz). The measured gain at 2.4 and 5.5 GHz is 2.1 and 6.1 dBi, respectively. The antenna shows a compact size of 25 × 30 × 0.8 mm. The details of the antenna design, the operation mechanism and the simulated and measured results are presented.

A coplanar waveguide-(CPW-) fed dual-band-notched antenna with sharp skirt selectivity for ultrawideband (UWB) applications is presented. The proposed antenna is composed of a radiant patch with a C-shaped slot and a C-shaped stub on the back surface of the substrate. By using the C-shaped slot and the C-shaped stub, dual-band-notched characteristics can be generated. In this way, a more practical and effective approach to design an UWB antenna with sharp notched-band-edge selectivity is developed. The measurement results show dual notched bands of 4.96-5.42 GHz and 5.71-5.91 GHz, which can reject the interference between IEEE 802.11a bands (5.15-5.35 GHz and 5.725-5.825 GHz) and UWB systems. The fabricated antenna shows good omnidirectional radiation patterns with acceptable gain and group delay.

Abstract-A compact microstrip-fed antenna with dual band-notched characteristics for ultrawideband (UWB) applications is presented.By introducing two open-ended inverted L-shaped slots, two sharp notches are achieved at frequencies of 3.16-3.70 GHz and 5.10-5.95 GHz for VSWR > 2. A rectangular slot in the ground plane can improve the impedance bandwidth of the proposed antenna. The prototype occupies a compact area of 22 × 26 mm 2 . The measurement results indicate that the proposed antenna can reject the interference with coexisting worldwide interoperability for microwave access (WiMAX) and wireless local area network (WLAN) systems. The proposed antenna shows relatively omnidirectional radiation patterns in the pass band.