Design of Multiband Antennas for LTE/WWAN/WLAN Smart Handheld Devices Applications

• Main Authors: Rio - Yao Li, 李日耀
• Other Authors: Cheng - Chi Yu
• Format: Others
• Language: zh-TW
• Published: 2017
• Online Access: http://ndltd.ncl.edu.tw/handle/639gu6

碩士 === 逢甲大學 === 通訊工程學系 === 105 === This thesis focuses on multi-band antennas for smart handheld device including handset and tablet computer. There are three antennas proposed in this research. The main structure of the antennas are slot antenna and monopole antenna. The first antenna is a slot antenna applied to the metal casing device. It can provide LTE 700/2300/2500 (698~787, 2300~2400, 2500~2690 MHz), GSM 850/900/1800/1900 (824~894, 890~960, 1710~1880, 1850~1990 MHz), UMTS 2100 (1920~2170 MHz) and WLAN 2400 (2400~2488 MHz). The slot antenna is constructed by a linear slot as the main structure. An I-shaped structure is disposed to improve performance. It can provides dual-wideband operation at the Lower band (698~960 MHz) and higher band (1710~2690 MHz). This antenna is suitable for today’s smart phone with metal casing device applications. The antenna overall size of 60×110×5 〖mm〗^3. The second multi-band antenna is designed for slim smart phone devices. It can operated at LTE 750/2300/2500 (746~798, 2300~2400, 2500~2690 MHz), GSM 850/900/1800/1900 (824~894, 890~960, 1710~1880, 1850~1990 MHz), UMTS 2100 (1920~2170 MHz) and WLAN 2400 (2400~2488 MHz). The main design adopted a three-branch monopole antenna and a shorting strip with a matching capacitor. A three-dimensional structure is designed to reduce the overall antenna size. The total antenna size is 55×6.5×4.8 〖mm〗^3. The only 6.5 mm non-ground height (clearness) makes it an ultra low profile mobile phone antenna. The proposed antenna is suitable for usefulness in today’s slim large-screen mobile phone device. Finally, we propose a dual-branch tablet computer antenna with a matching network. The antenna can cover the lower bands LTE 700 (698~787 MHz), GSM 850/900 (824~894, 890~960 MHz) and the higher bands LTE 2300/2500 (2300~2400, 2500~2690 MHz), GSM1800/1900 (1710~1880, 1850~1990 MHz), UMTS 2100 (1920~2170 MHz) and WLAN 2400 (2400~2488 MHz). A compensation inductance is used to reduce the required antenna length and achieve the effect of reducing the antenna size. A wideband matching network is integrated to the antenna to improve the lower band and higher band impedance bandwidth. The structure of the antenna is simple and easy to be manufactured. The antenna overall size is 35×10×6 〖mm〗^3.