串接式低雜訊放大器之增益平坦度與穩定度研究

Research on Gain Flatness and Stability for Cascade Low Noise Amplifier

林則孝(Tse-Hsiao Lin)

指導教授 ： 宋國明

國立臺北科技大學/電資學院/電資碩士在職專班研究所/碩士(2014年)

https://doi.org/10.6841/NTUT.2014.00084

摘要

本論文旨在研究與開發適用於數位廣播系統頻率標準(470MHz-862MHz)之低雜訊放大器，其具有高接收動態範圍能力。在設計方面，主要針對兩個問題作深入討論；第一個考量的是電路不穩定現象(K<1)，為了獲得高增益必須採用多級串接式放大器，容易造成電路不穩定現象；第二個則是考量增益平坦度不佳問題，因為在串接兩級低雜訊放大器之後，可能形成增益平坦度不佳的問題。本論文將針對上述兩個問題提出解決方案，即在串接後的低雜訊放大器之間置入一個以電感、電容、電阻元件所構成之中間級(Inter-Stage)電路，依量測結果顯示，本研究所設計之串接式低雜訊放大器具有低雜訊(NF<1)、高增益( Gain =40±0.5dB)、增益平坦度低於1 (Gain Flatness <±0.5dB) 與無條件穩定(K>1)等特性，其功耗0.9W並適用於數位廣播電視頻率(470MHz-862MHz)之接收機放大電路。

關鍵字

接收機 ； 低雜訊放大器 ； 增益平坦度 ； 穩定度 ； 增益等化

並列摘要

This thesis focuses on the research and development of cascade low noise amplifier circuit that works with high dynamic input rang and suits for Digital Vedio Broadcasting-Terrestrial(DVB-T) frequency.
There are two interest topics in this thesis, one is the unstability that caused by high linear gain of cascade low noise amplifier. Two is the gain flatness degradation which occurs with cascade LNA, This thesis proposes a solution to slove with those two issues, that is a inter-stage circuit considered with passive inductor, capacitor and resistor components. The goal of the cascade LNA not only obtain an unconditional stability, but also has good gain flatness.
The measurements present that the proposed cascade LNA possesses low noise figure(NF<1), High gain(40±0.5), good flatness(±0.5dB), and unconditional stable (K>1) with respect to the frequency from 470 to 862MHz for DVB-T receiver system.

並列關鍵字

Cascade ； Low Noise Amplifier ； Equalizer ； Stability ； Gain Flatness

參考文獻

[5] 捷倫科技股份有限公司，無線及微波雜訊指數量測基本概念，應用手冊，57-1，5952-8255ZHA，2000。

[6] 魏崇閔，應用於802.11a CMOS 低雜訊放大器設計與實作，碩士論文，大同大學電機工程研究所，臺北，2010。

[1] Inder J. Bahl, Fundamentals of RF and Microwave Transistor Amplifier, WILEY, New Jersey, 2009.

[3] M. E. Edwards and J. H. Sinsky, "A new criterion for linear 2-port stability using a single geometrically derived parameter, " IEEE Trans. Microwave Theory Tech., vol. 40, pp. 2303-2311, December 1992.

[11] Sungtek Kahng, Jeongho Ju, Wongyu Moon, "Design and implementation of the ghz-band wide(2~18GHz) linear equalizer," Journal of The Korea Electromagnetic Engineering Society, vol. 7, No1, Mar. 2007.