Miniature Dual-Band and Wideband Planar Inverted F-L-Antennas for Wireless Local Area Network and Ultra-Wideband Applications

By applying the magnetic wall concept, compact dual-band and wideband low-profile planar inverted F-L antennas for wireless local area network (WLAN) (2.4 GHz/5.2 GHz) and ultra-wideband (UWB) applications are proposed. The dual-band antenna shows a relative bandwidth of 12% and 10.2% in the ISM-2400 and IEEE 802.11a frequency bands, respectively, at reflection coefficient |S 11 | ≤ −10 dB. By carefully tuning the geometry parameters of the dual-band design, the two resonant frequencies can be merged to form a wide bandwidth antenna to cover 3,000 to 5,400 MHz (57% relative bandwidth) for a similar reflection coefficient |S 11 |; this fully covers the lower band UWB (3.1-4.8 GHz) spectrum. The experimental and simulated results in terms of reflection coefficient, gain, radiation efficiency, and field pattern of the two antennas on a small finite ground plane of size 30 mm × 15 mm show good agreement.