低雜訊放大器及變壓器回授技術設計與研究

Abstract

近年來，隨著第五代行動通訊的蓬勃發展，毫米波技術的研究與應用已成為當今的主流趨勢。然而，隨著對更高頻寬和更優異傳輸速率的需求不斷增長，目前無線通訊頻率所主要集中的6 GHz以下頻段，已達到相當飽和的程度。因此，向更高頻率方向發展成為重要的技術趨勢。在這方面，K頻段、Ka頻段和V頻段被視為第五代行動通訊的主要潛在發展頻段。在無線通訊系統中，低雜訊放大器也扮演著系統的重要角色。因此，本論文聚焦於應用變壓器於毫米波低雜訊放大器的設計與研究。 本篇論文主要分為兩個部分: 第一部分描述以0.15微米砷化鎵偽形態高電子遷移率電晶體(GaAs pHEMT)製程所設計的K頻段低雜訊放大器(LNA)。其中使用變壓器回授(transformer feedback)進行設計，變壓器對放大器的低雜訊、寬頻與良好的輸入匹配的表現皆有幫助，但因為變壓器設計對金屬層數的需求導致其較常應用於金氧半場效電晶體(CMOS FET)製程，鮮少被砷化偽形態高電子遷移率電晶體製程所採用。此低雜訊放大器工作在15.3到24.8的3dB頻寬帶內，並且有20.7 dB的峰值增益，與1.72-4.09 dB的雜訊指數。 第二部分為應用於38/48 GHz雙頻段之低雜訊放大器，使用90奈米金氧半場效電晶體製程所設計。此電路於第一級使用三重耦合變壓器(TCT)來實現良好的輸入匹配去涵蓋放大器所應用之頻段範圍，並以P型金氧半場效電晶體用作電壓開關調控切換Ka/V雙頻段。此低雜訊放大器有著37.1-44.1/43.8-50.2GHz的3dB頻寬，並且有19.9/18.8dB的增益，與7.1-8.1/6.9-7.8 dB的雜訊指數。

In recent years, the vibrant expansion of fifth-generation mobile communication has propelled the research and application of millimeter wave technology into today's mainstream. However, with the escalating demand for higher bandwidth and superior transmission rates, the current concentration of wireless communication frequencies below 6 GHz has reached a considerable saturation point. Consequently, there is a pivotal shift towards higher frequency domains emerging as a significant technological trend. Within this context, the K-band, Ka-band, and V-band are identified as the primary potential development frequency bands for fifth-generation mobile communication. In wireless communication systems, the role of low-noise amplifiers is pivotal. Therefore, this paper is dedicated to exploring the design and investigation of low-noise amplifiers employing transformers. This thesis is divided into two main sections: The first part illustrates the design of a K-band low noise amplifier (LNA) using 0.15-μm GaAs pHEMT process. In this design transformer feedback technique is utilized, which facilitates some of amplifiers favorable characteristics such as low noise, wideband, and excellent input matching. However, due to the requirement for a certain number of metal layers in transformer design, it is more commonly applied in metal oxide semiconductor field-effect transistor (CMOS FET) processes and is seldom utilized in gallium arsenide pseudomorphic high electron mobility transistor processes (GaAs pHEMT). This low noise amplifier achieves a peak gain of 20.7 dB and a 1.72-4.09 dB noise figure across a 3-dB bandwidth from 15.3 to 24.8 GHz. The second part introduces a dual band low noise amplifier designed at 38/48 GHz using a 90-nanometer CMOS process. This circuit employs a triple-coupling transformer in the first stage to achieve excellent input matching, covering the frequency band range applied by the amplifier. Additionally, it employs P-type CMOS transistors as voltage-switching regulators to alternate between the 38/48 GHz dual-band. This low noise amplifier achieves a peak gain of 19.9 dB and a 7.1-8.1 dB noise figure across a 3-dB bandwidth from 37.1 to 44.1 GHz, and attains a maximum gain of 18.8 dB and a noise figure ranging between 6.9-7.8 dB across a 3-dB bandwidth extending from 43.8 to 50.2 GHz.