本論文以可重組式微波被動元件為設計目標，首先，提出一個具有四種不同電路功能的可重組式微波被動電路，中心頻率設計於0.5 GHz。藉由控制二極體開關改變微帶線的連接方式，可切換成分支線耦合器、鼠競耦合器、帶通濾波器與帶拒濾波器等四種不同的功能，整體電路尺寸為 130.2 mm × 104.9 mm，電氣尺寸在中心頻率 0.5 GHz 下為 0.4089 λg × 0.3294 λg。
其次，使用橋式T線圈(Bridged-T Coil)取代微帶線以縮小尺寸，於切換開關的部分則改以電晶體實現，並於砷化鎵積體電路製程實現積體化可重組式微波被動元件，其操作中心頻率為10 GHz，可切換為分支線耦合器、帶通濾波器與帶拒濾波器三種不同電路功能。整體電路尺寸為 1.796 mm × 1.331 mm，電氣尺寸在中心頻率 10 GHz 下為 0.060 λ0 × 0.044 λ0。
因應多頻、多模的操作需求，接續並發展雙頻可重組式微波被動元件設計，採用雙頻橋式T線圈(Dual-Band Bridged-T coil)為基本組件，達成雙頻帶的分支線耦合器及雙頻帶通濾波器兩種功能。電路操作中心頻率為9.5及24 GHz，同樣使用砷化鎵積體電路製程實現，整體電路尺寸為 1.361 mm × 1.15 mm，電氣尺寸在9.5 GHz為 0.043 λ0 × 0.036 λ0，在24 GHz 則為 0.11 λ0 × 0.09 λ0。

In this study, novel reconfigurable microwave passive components are proposed. First, a 0.5-GHz reconfigurable microwave circuit with four different circuit functions is presented. The four different functions are branch-line coupler, rat-race coupler, band-pass filter, and band-stop filter, which are achieved by using the p-i-n diode switches to change the interconnections of the microstrip lines. A design example in PCB is presented, and the circuit size is 130.2 mm × 104.9 mm, while the electrical size is around 0.4089 λg × 0.3294 λg at 0.5 GHz.
Secondly, a 10-GHz on-chip reconfigurable microwave passive component in GaAs pHEMT process is presented. By using bridged-T coils to replace the microstrip lines for circuit area reduction, and by using transistors to realize the switches, it can be switched to three different functions including branch-line coupler, band-pass filter, and band-stop filter. The circuit size is only 1.796 mm × 1.331 mm while the electrical size is around 0.060 λ0 × 0.044 λ0 at 10 GHz.
Driven by the demand of multi-frequency and multi-mode wireless communication apparatus, the design of a dual-band on-chip reconfigurable microwave passive component is also developed. Dual-band bridged-T coils are employed as the building blocks, and the functions of a dual-band branch-line coupler and a dual-band band-pass filter are achieved in a single circuit. The operating frequencies are set as 9.5 and 24 GHz, and it is also implemented using a GaAs pHEMT process. The circuit size is only 1.361 mm × 1.15 mm. The corresponding electrical size is around 0.043 λ0 × 0.036 λ0 at 9.5 GHz and 0.11 λ0 × 0.09 λ0 at 24 GHz.

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