本論文研製一個具有多頻帶圓形單極天線。天線結構包含一個微帶線饋入之圓形單極天線和寄生的金屬環狀金屬結構及槽孔結構。圓形單極天線為一寬頻天線，天線設計上利用結構之多重路徑（multi-path）效應，產生較傳統單極天線更寬之操作頻帶。本文所提出之多頻帶天線設計，乃利用圓形單極天線之寬頻特性結合寄生環狀金屬及槽孔結構之共振效應，形成多個操作頻帶。本論文中將利用上述原理設計操作於三頻帶與四頻帶之天線。其中，三頻帶天線之操作頻帶分別為2.4至2.69 GHz（802.11、802.11b、802.11g、802.11n、WiMAX）, 3.4至3.69 GHz（WiMAX），以及5.15至5.85 GHz（802.11a、WiMAX）。四頻帶天線之操作頻帶分別為824至960MHz （GSM850、GSM900），1.71至2.69 GHz （GSM1800、GSM1900、UMTS、802.11、802.11b、802.11g、802.11n、WiMAX），3.4至3.69 GHz（WiMAX），以及5.15至5.85 GHz（802.11a、WiMAX）。所設計之天線經由實作量測驗證，模擬與量測之操作頻寬與輻射特性一致。所提出之天線可應用於多頻帶無線通訊系統之收發天線。 The design and analysis of multiband planar disk monopole antenna are presented. The proposed antenna structure consists of a microstrip fed disk monopole and parasitic rings and slots. Technically, the proposed antenna design exploits the broadband characteristic of the disk monopole, and multiple operation bands are achieved by incorporating parasitic resonator elements into the antenna structure. The unwanted operating frequencies associated with the disk monopole are eliminated through the band notches attributed to the resonance of the parasitic elements. Compared to past multiple-band antenna designs, the proposed antenna design is relatively straightforward and the antenna structure is planar in nature. Two antennas are demonstrated for experimental verification. One is of operating frequencies from 2.4 to 2.69 GHz, 3.4 to 3.69 GHz, and 5.15 to 5.85 GHz. The other is of operating frequencies from 824 to 915MHz, 1.71 to 2.69 GHz, 3.4 to 3.69 GHz, and 5.15 to 5.85 GHz. The measured and simulated results of both demonstrated antennas are in good agreement. The proposed antenna design can be employed for realization of the transceiving antennas of multiband wireless communication systems
