本文選題：衛(wèi)星導(dǎo)航系統(tǒng) + 混頻器��； 參考：《西安電子科技大學(xué)》2015年碩士論文

【摘要】：北斗衛(wèi)星導(dǎo)航系統(tǒng)是我國(guó)自主研發(fā)建設(shè)的導(dǎo)航系統(tǒng),它的建設(shè)和完善勢(shì)必對(duì)國(guó)民經(jīng)濟(jì)和社會(huì)發(fā)展產(chǎn)生巨大的推動(dòng)作用。地面接收終端是導(dǎo)航實(shí)現(xiàn)的關(guān)鍵環(huán)節(jié),混頻器作為導(dǎo)航接收機(jī)中的核心模塊之一,其電路性能與導(dǎo)航接收機(jī)系統(tǒng)的總體性能息息相關(guān),因此對(duì)接收機(jī)中混頻器模塊的設(shè)計(jì)研究具有重要意義。本文基于TSMC 0.18um RF CMOS工藝設(shè)計(jì)了一種折疊正交雙平衡結(jié)構(gòu)的混頻器。該結(jié)構(gòu)的混頻器與傳統(tǒng)的吉爾伯特單元混頻器相比具有以下優(yōu)點(diǎn):采用折疊的開(kāi)關(guān)級(jí),提高了端口間的隔離度;采用電流源做負(fù)載,提高了混頻器增益;采用共模反饋電路為混頻器各個(gè)關(guān)鍵節(jié)點(diǎn)提供穩(wěn)定的工作點(diǎn),提高了混頻器的線性度;采用同相和正交兩個(gè)混頻器支路共用一組射頻輸入端口,在實(shí)現(xiàn)了正交混頻的同時(shí)降低了電路的功耗。本文首先闡述了接收機(jī)和混頻器的理論知識(shí)。在混頻器電路設(shè)計(jì)過(guò)程中,本文對(duì)傳統(tǒng)的吉爾伯特單元混頻器進(jìn)行理論分析,然后對(duì)其進(jìn)行了優(yōu)化和改進(jìn),從而設(shè)計(jì)完成了一種折疊正交雙平衡結(jié)構(gòu)的有源混頻器。隨后本文對(duì)折疊正交雙平衡混頻器電路的轉(zhuǎn)換增益和噪聲系數(shù)兩個(gè)重要指標(biāo)進(jìn)行了詳細(xì)的理論分析,推導(dǎo)出影響轉(zhuǎn)換增益和噪聲系數(shù)的關(guān)鍵因素和相關(guān)參數(shù);根據(jù)晶體管跨導(dǎo)效率與過(guò)驅(qū)動(dòng)電壓的關(guān)系曲線以及晶體管參數(shù)對(duì)增益和噪聲的影響,從而確定了電路中晶體管的過(guò)驅(qū)動(dòng)電壓和跨導(dǎo);通過(guò)分析工藝條件和晶體管參數(shù)對(duì)混頻器性能的影響,確定了電路中各晶體管的溝道長(zhǎng)度;設(shè)計(jì)共模反饋電路為混頻器各個(gè)關(guān)鍵節(jié)點(diǎn)提供穩(wěn)定的共模電壓。本文使用ADS與Cadence軟件分別對(duì)于所設(shè)計(jì)的混頻器進(jìn)行了前仿真、版圖設(shè)計(jì)以及后仿真。ADS前仿真結(jié)果顯示,在射頻輸入信號(hào)頻點(diǎn)1.561GHz處,所設(shè)計(jì)的混頻器轉(zhuǎn)換增益為24d B,噪聲系數(shù)9.3dB,三階互調(diào)截點(diǎn)-19dB,線性度良好,隔離度大于150dB,功耗為3.8mA×1.8V,前仿真顯示論文所設(shè)計(jì)的混頻器電路完全滿足設(shè)計(jì)要求。使用Virtuoso工具所設(shè)計(jì)的混頻器版圖面積為230um×320um,后仿真結(jié)果顯示:混頻器轉(zhuǎn)換增益為22dB,噪聲系數(shù)11dB,三階互調(diào)截點(diǎn)-18dB,隔離度大于70dB,功耗3.8mA×1.8V,后仿真結(jié)果變化的主要原因是版圖中寄生參數(shù)的加入影響了仿真性能。本文的研究對(duì)導(dǎo)航接收機(jī)中混頻器的設(shè)計(jì)具有借鑒意義。
[Abstract]:Beidou satellite navigation system is a navigation system developed independently in China, and its construction and improvement will certainly have a great role in promoting the development of national economy and society. The ground receiving terminal is the key link of navigation. As one of the core modules of navigation receiver, the circuit performance of mixer is closely related to the overall performance of navigation receiver system. Therefore, it is of great significance to study the design of mixer module in receiver. Based on TSMC 0.18um RF CMOS process, a folded quadrature double balance mixer is designed in this paper. Compared with the traditional Gilbert cell mixer, the mixer with this structure has the following advantages: the folded switch level is used to improve the isolation between ports, the current source is used as the load, and the mixer gain is improved. The common-mode feedback circuit is used to provide stable operating points for each key node of the mixer, which improves the linearity of the mixer. The quadrature mixing is realized and the power consumption of the circuit is reduced. In this paper, the theoretical knowledge of receiver and mixer is introduced. In the design of mixer circuit, the traditional Gilbert unit mixer is analyzed theoretically, then optimized and improved, and an active mixer with folded quadrature dual balance structure is designed. Then, the conversion gain and noise coefficient of folded quadrature double balanced mixer circuit are analyzed in detail, and the key factors and related parameters that affect the conversion gain and noise coefficient are deduced. According to the relation curve between transistors' transconductance efficiency and overdrive voltage and the influence of transistor parameters on gain and noise, the overdrive voltage and transconductance of transistors in the circuit are determined. By analyzing the influence of process conditions and transistor parameters on the performance of the mixer, the channel length of each transistor in the circuit is determined, and a common mode feedback circuit is designed to provide stable common-mode voltage for each key node of the mixer. In this paper, ADS and Cadence software are used to simulate the mixer, layout design and post-simulation. Ads simulation results show that the RF input signal frequency point 1.561GHz, The designed mixer has a conversion gain of 24 dB, a noise coefficient of 9.3 dB, a third-order intermodulation intercept point of -19 dB, a good linearity, an isolation degree of more than 150dB and a power consumption of 3.8mA 脳 1.8 V. the pre-simulation results show that the mixer circuit designed in this paper fully meets the design requirements. The layout area of mixer designed with Virtuoso tool is 230um 脳 320um. The simulation results show that the conversion gain of mixer is 22 dB, the noise coefficient is 11 dB, the third order intermodulation intercept point is -18 dB, the isolation degree is greater than 70 dB, and the power consumption is 3.8mA 脳 1.8 V. The addition of parasitic parameters affects the simulation performance. The research in this paper can be used for reference in the design of mixer in navigation receiver.
【學(xué)位授予單位】：西安電子科技大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2015
【分類號(hào)】：TN773;TN965.5

【參考文獻(xiàn)】

相關(guān)期刊論文 前4條

1 成躍進(jìn);;現(xiàn)代衛(wèi)星導(dǎo)航定位系統(tǒng)發(fā)展介紹[J];空間電子技術(shù);2015年01期

2 康向陽(yáng);;中國(guó)的GPS-北斗導(dǎo)航系統(tǒng)[J];天津航海;2007年01期

3 周先軍;胡修林;張?zhí)N玉;王甲池;;超寬帶無(wú)線通信關(guān)鍵技術(shù)[J];電子技術(shù)應(yīng)用;2005年10期

4 李智群,王志功;零中頻射頻接收機(jī)技術(shù)[J];電子產(chǎn)品世界;2004年13期

，

本文編號(hào)：1784539