本論文以微型化毫米波雙頻分支線耦合器為研究目標，設計上使用雙頻橋式T線圈(Bridged-T Coil, BTC)取代傳輸線，同時達到電路尺寸微型化與雙頻操作的效果，並且建構加入導體損耗與介質損耗之有損橋式T線圈模型，以分析雙頻橋式T線圈各元件的損耗。 首先，以WIPD製程實現sub-6GHz頻段的雙頻分支線耦合器，以串接雙頻橋式T線圈取代傳輸線，實現兩個操作頻率具同相位輸出之雙頻分支線耦合器，其電路面積為4mm × 3mm，中心頻率分別為1.85GHz與5.8GHz，在中心頻率之電氣尺寸分別為0.02λ0 × 0.02λ0與0.08λ0 × 0.06λ0。接著將操作頻率提升至毫米波頻段，分別以WIPD製程與90nm CMOS製程實現雙頻分支線耦合器，以WIPD製程實現之18.7/38.5GHz雙頻分支線耦合器，其電路面積為1.5mm × 1.4mm，在中心頻率之電氣尺寸分別為0.09λ0 × 0.08λ0與0.19λ0 × 0.18λ0。以90nm CMOS製程實現之18.7/38GHz雙頻分支線耦合器，其電路面積為0.5mm × 0.5mm，在中心頻率之電氣尺寸分別為0.03λ0 × 0.03λ0與0.07λ0 × 0.07λ0。 上述實作電路成功驗證將雙頻橋式T線圈用於毫米波頻段雙頻元件設計的可行性。 ;In this thesis, miniaturized of millimeter wave dual-band branch line couplers are proposed. By replacing the transmission lines in a conventional branch-line coupler with bridged-T coils, the circuit size reduction and dual-band operation can be achieved simultaneously. Additionally, a lossy bridged-T coil model incorporating frequency-dependent conductor loss and dielectric loss is constructed to analyze the loss of each component of the dual-band bridged-T coil. First, a 1.85/5.8-GHz dual-band branch-line coupler is implemented using the WIPD process. By cascading the dual-band bridged-T coils to replace the λ/4 transmission line, a dual-band branch line coupler with the same phase difference at two operating frequencies are achieved. The circuit size is 4mm × 3mm while the electrical size is around 0.02λ0 × 0.02λ0 at 1.85GHz and 0.08λ0× 0.06λ0 at 5.8GHz. Next, the operating frequencies are raised to millimeter wave band, and two dual-band branch line couplers are implemented in WIPD process and 90nm CMOS process. The circuit size of the proposed18.7/38.5-GHz dual-band branch-line coupler in WIPD is 1.5mm × 1.4mm. The corresponding electrical size is around 0.09λ0 × 0.08λ0 at 18.7GHz and 0.19λ0× 0.18λ0 at 38.5GHz. The circuit size of the porposed 18.7/38-GHz dual-band branch line coupler in CMOS is 0.5mm × 0.5mm, while the corresponding electrical size is around 0.03λ0 × 0.03λ0 at 18.7GHz and 0.07λ0× 0.07λ0 at 38GHz. These two dual-band coupelrs successfully verify the feasibility of bridged-T coils for realizing dual-band circuit components in the millimeter wave band.
