具抑制頻寬外增益功能之帶斥特性超寬頻低雜訊放大器與2.5-11GHz 主動式寬頻匹配超寬頻低雜訊放大器

Abstract

本論文描述應用在超寬頻系統中低雜訊放大器之分析與設計。超寬頻低雜訊放大器需具備有寬頻、增益平坦的特性。 第一部份為具抑制頻寬外增益功能之帶斥特性超寬頻低雜訊放大器，一開始先設計LC諧振匹配超寬頻低雜訊放大器，其量測結果如下，頻寬3.1~10GHz，增益5± 2dB，S11<-4dB，S22<-8.5dB，消耗功率為16.2 mW。接著進階再設計了具抑制頻寬外增益功能之帶斥特性超寬頻低雜訊放大器，其模擬結果如下，頻寬3.1~9GHz，3.1~5GHz，增益12± 1.2dB，6~9GHz，增益10±0.5dB，S11<-9.5dB，S22<-10dB，最低的雜訊指數為3.48 dB。消耗功率為 22mW。 第二部份為2.5-11GHz主動式寬頻匹配超寬頻低雜訊放大器，利用了多級的概念來設計，並且選擇共閘級做為第一級放大器，中間加上一級共源級疊接組態來提高整體增益，最後再加上一級電壓追隨器達到輸出阻抗匹配。這個寬頻低雜訊放大器其量測結果如下，頻寬為2.5~11GHz，增益為7.5 dB ±0.5dB，S11<9.9dB，S22<-12dB，消耗功率為18.9 mW。

This thesis describes the design and analysis of low-noise amplifier for UWB system. The features of the UWB LNA are wide bandwidth and flatness of gain. The first part studies on a band-notch ultra-wideband LNA with band shaping capability.For a start , the measured performances of a LC resonance matching ultra-wideband LNA are as follow: The bandwidth of the LNA is ranged from 3 GHz to 10 GHz. The gain is 5 dB ± 2 dB. The input return loss is below -4dB. The output return loss is below -8.5dB . The power consumption is 16.2 mW. The simulation performances of a band-notch ultra-wideband LNA with band shaping capability are as follow: The bandwidth of the LNA is ranged from 3 GHz to 9 GHz. For 3GHz to 5GHz, the gain is 12 dB ± 1.2 dB. For 6GHz to 9GHz, the gain is 10 dB ± 0.5 dB.The input return loss is below -9.5dB. The output return loss is below -10dB . The minimum noise figure is 3.48dB and the power consumption is 22 mW. The second part studies on a 2.5-11GHz active matching Ultra-wideband Low Noise Amplifier. We utilize the concept of multi-stages to design this circuit. The first stage is a common gate topology and a Cascode amplifier is in the middle stages and the final stage is a voltage follower. the measured performances of a 2.5-11GHz active matching Ultra-wideband Low Noise Amplifier are as follow: The bandwidth of the LNA is ranged from 2.5 GHz to 11 GHz. The gain is 7.5 dB ± 0.5 dB. The input return loss is below -9.9dB. The output return loss is below -12dB . The power consumption is 18.9 mW.