本研究主旨為設計一個雙層印刷電路板結構的79 GHz透射陣列天線，透過相對簡單的結構，在不使用金屬貫孔提升透射大小的情況下達到足夠的可控透射相位量，降低製作成本和設計時間。製作於W頻帶之透射陣列天線單元通常需要透過複雜的結構或設計方式如金屬貫孔、空氣柱、複合材料以及多層設計等，來達到足夠的透射相位量。為了解決雙層金屬層透射相位量不足的問題，吾人透過整合不同設計的透射陣列天線單元，以共振長度在半波長的十字槽孔設計單元及共振長度在一倍半波長的方環形槽孔互相補償彼此不足的透射相位，並加入相位延遲線的設計概念，使用共三種不同設計的單元來達到335 ˚的可控透射相位量，並且藉由MATLAB協助計算以找出最佳化的相位補償排列方式，最後透過實作及量測驗證本研究之透射陣列天線的輻射效果及場型，本研究架構具有以下特色：1)金屬層數以兩層為限；2)結構盡量簡單且限制不使用空氣柱或金屬貫孔的設計，以降低製作難度及成本；3)涵蓋相位量大於315 °(優於文獻紀載)。
本研究最終成品能夠提供雙線性極化之29 dBi增益、旁瓣電平為-21 dB、3 dB增益頻寬為12.6 %，而孔徑效率為36.7 %。

This study aims at designing a 79-GHz transmitarray suing dual-layered printed circuit board (PCB) technology without vias. Sufficient controllable transmitting phase is achieved without using metal vias, thereby reducing both production costs and design complexity. Traditional transmitarray elements operating in the W-band often require complex structures or design techniques such as metal vias, air gaps, composite materials, and multilayer designs to achieve the desired transmit phase. To overcome the limitation on transmitting phase variation when using in a dual-layered PCB without vias, this study integrates three difference transmitarray elements, including a cross-slot unit cell with a resonant length of half-wavelength and a annular slot unit cell whose resonant length is one and a half wavelengths. These transmitting phase ranges of the elements are complementary to one another to broaden the overall phase coverage, and phase delay lines are introduced to achieve a controllable transmitting phase up to 335°. MATLAB codes are employed to optimize the arrangement of phase compensation. The designed transmitarray is implemented and measured to verify its radiation characteristics and field patterns. This research has the following features: 1) fabricated on a double layer PCB; 2) no pillars or vias was used, thereby, reducing the manufacturing complexity and costs; 3) achieving a phase coverage greater than 315o, wider than that reported in literature (in the same band).
The final design fulfills a dual linearly polarized transmitarray with a gain of 29 dBi, a sidelobe level of -21 dB, a 3 dB bandwidth of 12%, and an aperture efficiency of 36.7%. This study significantly reduces design and production costs through a simple structure.

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