本論文提出應用於毫米波系統之串聯式圓極化H形貼片天線陣列設計。H形貼片天線陣列主要是由兩個不同金屬層的T形貼片天線所組成，藉由兩貼片天線間的耦合來產生相位差90度，並調整兩貼片天線的尺寸來達到大小相同、空間中相互正交的兩電場，來達到圓極化的效果。一般在使用線極化天線傳輸或接收電磁波的過程當中會受到多重路徑所產生的極化損耗之影響，因此為了提高傳輸訊號的品質與穩定度，須仰賴圓極化天線來做為傳輸或接收的工具。
本設計是使用微帶線串聯式饋入的方式來實現H形圓極化貼片天線陣列，在天線陣列的尾端使用天線來取代匹配電阻。天線陣列的設計是使用RO4003C的板材，板材結構為三層金屬兩層介質。
本設計的圓極化H形天線陣列，單個天線單元｜S11｜的量測頻寬21.4% (25.05~31.04 GHz)，軸比頻寬8.6%(26.00~28.35GHz)，增益達3.1 dBic 在28.5 GHz;四個單元天線陣列｜S11｜的量測頻寬20.2%(25.44~31.17 GHz)，軸比頻寬3.4% ( 28.90 ~ 29.90 GHz )，增益達6.8 dBic在28.5 GHz。

Designs of Series-Fed Circularly-Polarized H-Shaped Patch Antenna Arrays for Millimeter-Wave Applications are proposed in the thesis. The proposed H-shaped patch antenna array is mainly composed of two T-shaped patch antennas with different metal layers, and the phase difference of 90 degrees is generated by the coupling between the two patch antennas. By adjusting the size of the two patch antennas to make the same power and two orthogonal of electric fields in space, the effect of circular polarization is achieved. Generally, when using linearly-polarized antennas, the transmission or receiving of the electromagnetic wave is often influenced by the polarization loss of multiple path. In order to increase quality and stability of transmitted signal, the circularly-polarized antenna is a reliable tool of transmission or reception.
In this design, the H-shaped circularly polarized patch antenna array is series-fed with microstrip, and an antenna is used at the end of the antenna array to replace the terminating load. The design of the antenna array is made of RO4003C substrate, the substrate structure is composed of three metal layers and two dielectric layers.
For the single-element antenna, the measured impedance bandwidth is 21.4% (25.05~31.04 GHz), axial ratio bandwidth is 8.6% (26.00~28.35 GHz), and the gain is 3.1 dBic at 28.5 GHz; For the 4-element antenna array, the measured bandwidth is 20.2% (25.44~31.17 GHz), the axial ratio bandwidth is 3.4% (28.90~29.90 GHz), and the gain is 6.8 dBic at 28.5 GHz.

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