A Study of Antennas for Wireless Devices

• Main Authors: LIU,WEI-CHENG, 劉威呈
• Other Authors: TSAI,WEN-SHING
• Format: Others
• Language: zh-TW
• Published: 2016
• Online Access: http://ndltd.ncl.edu.tw/handle/2xd9ge

碩士 === 明志科技大學 === 電機工程系碩士班 === 104 === During the last few years, wireless communication device has been developed with amazing results. For antenna requirements including size of the antenna or frequency bands are also getting higher and higher. In the thesis, two kinds of antennas are proposed, including a compact triple band USB dongle with loop-coupled and a compact UWB antenna with asymmetric ground. The first one is the USB dongle antenna which size is 10(W)X50(L)X0.8(H)mm3, which operating bands are WLAN(2.4-2.484GHz, 5.15-5.35GHz, 5.725-5.85GHz) / WiMAX(2.3-2.69GHz, 3.4-3.7GHz, 5.25-5.85GHz). This antenna is using λ/4 path of monopole antenna for fed into, then using loop-coupled to achieve three operating bands, and accord reflection coefficient (S11)<-10dB. The second one is the UWB antenna which size is 20(W)X25(L)X0.8(H)mm3, which operating band is UWB(3.1-10.6GHz). This antenna is an octagon structure with micro-strip line fed, then using asymmetric of ground to extend electric current length. Finally we adopt stub and slot to achieve dual band-notched purpose. As mentioned above, the simulated and measured results are obtained by using Ansoft HFSS software and network analyzer Angilent E8362B respectively. By OTA testing technology, we use the EMQuest system to measure 2D and 3D field pattern. At the Results, antenna radiation pattern is near to the omni-directional.