Compact loop-coupled spiral antenna for multiband wireless USB dongles
A compact spiral antenna with a loop element for wireless USB dongle devices is proposed. The proposed loop-coupled spiral antenna covers the WiBro, Bluetooth, WLAN, WiMAX and satellite digital multimedia broadcast (S-DMB) bands. The overall dimensions of the fabricated antenna are 10×50×1 mm, which is the most compact dimension among multiband USB dongle antennas reported to date. The measured −10 dB reflection bandwidths for two resonant frequencies are 19.0% (2.29–2.77 GHz) and 27.6% (4.55–6.01 GHz). The measured peak gain of the antenna is 3.92 dBi.