摘要
在許多的天線當中，以微帶天線的體積小、輕、易於製造且容易與其他電路整合，而更加的被重視。且漏波式天線具有邊傳邊漏的特性可促使頻寬增大，且利用微帶線饋入方式於多層結構讓整個天線的設計增加更多可變異參數。 本論文包括有兩個研究方向：第一、輻射場形的波束指向隨著頻率改變而改變的天線設計；第二、在固定的操作頻率點下，輻射場形的波束指向可調的天線設計。論文中，第一部分探討漏波天線的傳播常數中-衰減常數以及相位常數對於天線場型波束的影響。第二部分是利用電磁模擬軟體分析天線結構，探討此天線在不同結構下，對反射損耗之影響。以及探討不對稱性饋入線和輻射層所造成的耦合效應，進而達成使筆狀輻射波束具可掃描的特性。第三部份則以設計好的天線做延伸，將輻射層上的貼片天線尺寸在固定的範圍（半徑? 8.5 mm）下做變化，探討輻射層的電流相位分布，及其對輻射場形變化的影響，達成可在固定操作頻率點下進行波束掃描的功能。 應用於波束掃描之堆疊式天線設計有利於天線之遠場輻射判斷，進而掌握此天線之特性，方便於日後之應用。
並列摘要
Microstrip antennas have received much attention due to their low profile, light-weight, ease for fabrication and integration with circuit. The traveling-type leaky-wave microstrip antenna can provide wide-band frequency range and the employing of double-layer structure offers antenna more various parameters to adjust in order to satisfy various demands. The aim of this work includes two aspects, 1) Antenna design for frequency dependent beam scanning function and 2) Antenna design for beam scanning function as the operating frequency fixed. The first topic studies the effect of complex propagation constant including both the attenuation constant and the phase constant to the direction of radiation pattern for a leaky wave antenna. The second topic is to obtain the optimal geometry parameters for the proposed antenna prototype from the electromagnetic solver. A study on effects of the asymmetric feedline and layer structure to beam scanning characteristic has also been done in this part. Finally, the beam scanning characteristic has been investigated by changing the dimension of radiating patch, which was printed on the topic layer, within the range of radius ?8.5 mm as the operating frequency was fixed. Stacked antenna design for beam steering can be used to compute other antenna parameters such as far-field radiation, therefore antenna characteristics can be controlled effectively for future applications.