本論文研究主要為超寬頻(Ultra wideband, UWB)及應用於24 GHz的低雜訊放大器(Low Noise Amplifier, LNA),電路採用0.15 μm pHEMT製程進行設計。論文中分別使用負回授式、電流再利用架構與串接式之電路架構,並對其模擬與量測結果進行分析與比 較。 第一部份超寬頻低雜訊放大器可應用於通訊規格IEEE802.15.3a的標準中,採用負回授式與電流再利用的架構,因為負回授式具有使增益較為平坦與良好的輸入阻抗匹配,並可增加電路的穩定性,而電流再利用架構則是可以提供高增益與降低消耗功率的優點,接著再使用共源極退化式電感,透過調整電感Lg與Ls的數值大小進行輸入端的匹配。此低雜訊放大器所量測到的數值如下,增益為15.79 dB~18.72 dB,雜訊指數為2.68 dB~4.20 dB,輸入與輸出的反射係數分別為-13.67 dB~-6.41 dB與-15.48 dB~-8.95 dB,而反向隔離度為-41.29 dB~-38.36 dB。 第二部份為設計一個應用於24 GHz的低雜訊放大器,此設計可以應用於車用雷達中,主要電路架構使用電流再利用架構,再串接一級放大器,串接放大器具有增加增益的優點,前端使用電容、電感和退化電感做為輸入阻抗的匹配,而輸出端則是使用電感與電容做為輸出的阻抗匹配。此低雜訊放大器所量測的增益為6.41 dB,雜訊指數為6.21 dB,輸入反射係數為-8.53 dB,輸出反射係數為-22.44 dB而反向隔離度為-26.49 dB。
This thesis presents the design of an ultra-wideband low noise amplifier and a 24 GHz low noise amplifier. Both of them using WIN 0.15 μm pHEMT process to design the circuit. This reach adopted resistance feedback, current reused, and cascade architectures. This research compares simulation and measurement results. At first, an ultra wideband low noise amplifier was designed for the application of IEEE802.15.3a standard. The adopted structure is the resistance feedback which provides a flat gain, good input impedance match, and better stability condition for the amplifier circuit. The other adopted structure is the current reused were adopted to achieve a high gain and small power consumption. The source degeneration inductors adjust the input impedance matching. The measurement results have gain 15.79 dB~18.72 dB, noise figure 2.68 dB~4.20 dB, input return loss -13.67 dB~-6.41 dB, output return loss -15.48dB~-8.95 dB, and isolation -41.29 dB~-38.36 dB. A voltage source of 4.5 V is applied with power consumption 607.5 mW. In the second part, a low noise amplifier was designed in 24 GHz for a car radar detector. The main circuit architecture using current reused and cascade architectures. The cascade architecture was employed to achieve high gain. Front end using capacitors, inductors, and degeneration inductor to realize the input impedance matching. The output terminal used inductors and capacitors for the output impedance. The low noise amplifier achieve the following simulation results gain 6.41 dB, noise figure 6.21 dB, input return loss -8.53 dB, output return loss -22.44 dB, and isolation -26.49 dB. A voltage source of 1.2 V is applied with power consumption 114.00 mW.