本研究之主旨，以實際應用為前提，研製兩款非福斯特元件整合於天線之微型化設計。該設計之基礎，乃因非福斯特電路具有負電抗特性，若作為匹配網路，將可打破以往傳統匹配網路所帶來的頻寬限制。此電路可以透過負阻抗轉換器與電抗負載元件來實現，整體來說，兩款天線設計再加入負阻抗轉換器作為匹配網路之後，皆具有尺寸縮小及頻寬增加之特點。
本論文首先整理現今負阻抗轉換器該領域之已有理論，針對浮動、單端負阻抗轉換器進行詳細介紹。接著，分別對偶極天線與倒F 天線進行浮動負阻抗轉換器與單端負阻抗轉換器的匹配設計，經充分考量其穩定性、走線耦合等非理想效應，乃將電路與天線整合以完成最終設計。經實驗證實，兩款天線加入非福斯特匹配網路皆能有效改善小天線頻寬偏窄的問題，輻射場型也與模擬有相當程度的吻合。
綜上所述，本論文藉由正確的設計流程，成功實現負阻抗轉換器之電路，也透過與天線整合設計，驗證了非福斯特電路確實有小型化且增加天線操作頻寬的效果，更證實了負阻抗轉換器在天線工程應用中的可行性和有效性。

This study focuses on the development of two Non-Foster miniaturized antennas suitable for practical applications. Two non-Foster elements, implemented by negative impedance converters (NICs), were integrated with electrically small antennas to achieve size miniaturization and broadband operation simultaneously.
Benefitting from the negative reactance characteristic non-Foster circuits demonstrate, the bandwidth limitation of traditional antenna matching networks can be alleviated.
In this thesis, a design flow for integrating NICs with electrically small antennas is reviewed, investigated and summarized. The theoretical background of the floating and single-ended NICs is first presented. The floating and single-ended NICs are then integrated with a balanced dipole antenna and a single-ended IFA antenna, respectively, as non-Foster antennas. The stability test as well as mutual coupling effect is taken into account and the antennas are fabricated and tested. The experimental results show a significant improvement in the impedance bandwidth, and there is a good agreement between the simulated and measured radiation patterns.
It confirms the feasibility and effectiveness of Non-Foster elements in antenna engineering applications.

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