呂學士臺灣大學：電子工程學研究所劉凱尹Liu, Kai-YinKai-YinLiu2007-11-272018-07-102007-11-272018-07-102005http://ntur.lib.ntu.edu.tw//handle/246246/57476本論文使用UMC 0.18CMOS 製程，研製可以適用於802.11a/b/g WLAN 直接降頻接收機架構的類比基頻電路。電路設計上分成兩部份來實現，第一個部份是七階的柴比雪夫通道選擇濾波器；而第二個部份為自動頻率校正迴路。 七階柴比雪夫通道選擇濾波器的設計上，採用主動電阻電容的濾波器架構，以串接方式來實現高階低通濾波器的原型。通道選擇濾波器本身可以調變增益，並可調變頻寬來適用於不同的WLAN標準，並包含伺服迴路以解決直流漂移電壓問題。根據量測結果，通道選擇濾波器具有20dB至60dB的增益，每次調變增益為10dB。三個操作頻帶的3dB頻率分別為7.56MHz, 19.5MHz, 以及26.5MHz。此外針對不同的操作頻帶，也做了雜訊以及線性度的分析與量測。晶片面積為1.15*1.45 mm2，消耗功率為22.248mW。 自動頻率校正迴路是用來解決主動濾波器本身頻率精確性的問題，採用主僕式架構來實現。使用二分逼近法來調整濾波器中的電容陣列值，達到頻率校正的目的。為先驗證自動頻率校正電路功能，先實現自動頻率校正電路於二階低通濾波器，針對二階電路做頻率校正。根據量測結果，校正頻率範圍為4.3MHz至11.34MHz。晶片面積為1.5*1.33mm2，消耗功率10.8mW。This thesis presents the design and implements the analog baseband for 802.11a/b/g WLAN direct-conversion receiver architecture in UMC 0.18um CMOS process. The whole baseband function is verified by two chips. One is the seventh-order chebyshev channel selection filter, and the other is the automatic frequency tuning loop. The filter type of the seventh-order chebyshev channel selection filter is active-rc, and cascade method is applied to implement this high-order filter. The filter itself can switch the gain-level and bandwidth for different WLAN standards. Servo-loop in the filter can solve the issue of dc-offset. According to measurement results, the gain level of the filter is form 20dB to 60dB in 10dB steps. The f3dB for different operating bandwidth are 7.56MHz, 19.5MHz, and 26.5MHz. Besides, the noise and linearity are analyzed for different operating bandwidth. The die area is 1.15*1.45 mm2 and the power consumption is 22.248mW. Automatic frequency tuning loop is used for solving the inaccuracy of the active filter bandwidth. It is implemented in the master-slave method. The cap array values of the filter are determined by the binary-search to self-calibrate the filter bandwidth. In order to verify the function of the ATL, we apply second-order biquad as the slave filter. According to the measurement results, the calibration frequency range is from 4.3MHz to 11.34MHz. The die area is 1.5*1.33mm2, and the power consumption is 10.8mW.Chapter 1 Introduction………………..……………………..……………..…1 1.1 Motivation………………………………………….…..…1 1.2 Thesis Organization………………………….……….…2 Chapter 2 System and Filter Specification…………….………………..…3 2.1 Wireless LAN Standards…………………………………………3 2.2 Receiver Architectures……………………………………..…5 2.3 Filter Specification………………………………………..…7 Reference………………………………………..……………………11 Chapter 3 Operating Amplifier………………………..………………………13 3.1 Introduction to Operating Amplifier………………………13 3.2 Two-Stage OP-AMP Design………………………..……………15 3.3 Common Mode Feedback…………………….....………………19 Reference…………………………………………………..…………22 Chapter 4 Filter ……………………………….…...…………………………23 4.1 High-Order Filter…………….……...………………………23 4.2 Second-Order Biquad………………....………………………27 4.3 DC-Offset Cancellation…………………….…………………34 4.4 Output Buffer…………………………….…………….………38 4.5 Filter Simulation…………………………..…………………39 4.5.1 AC Response Simulation……………….……………………39 4.5.2 Noise Simulation……………………….................41 4.5.3 Linearity Simulation…………………….…………………45 4.5.4 Stability Simulation……………………………..….……48 4.6 Filter Layout……………………….………….………..……49 Reference……………………………...……………...……………54 Chapter 5 Automatic Frequency Tuning Loo……...………...……….……57 5.1 Introduction to Automatic Tuning Loop……..……..……57 5.2 Automatic Tuning Loop…………..…...….…………………59 5.2.1 Master-Filter……………………....………………………60 5.2.2 Basic ATL Concept……………...……...…………………66 5.2.3 System Clock………………….......………………………67 5.2.4 Comparator…………….…..........………………………70 5.2.5 Divide-by-Four…………….……....………………………72 5.2.6 Phase Frequency Detector & Charge Pump…….…………74 5.3 ATL Simulation…………………...……………………………76 5.4 ATL Layout…………………………...……..…………………78 Reference……………………….…………………...………………81 Chapter 6 Measurement………….……...………………………………………83 6.1 AC Response Measurement of Filter………..………………83 6.2 Noise Measurement of Filter……………......……………88 6.3 Linearity Measurement of Filter …………….……………93 6.4 ATL Measurement ………………...……………..……………99 Reference……………....…………………...………………..…101 Chapter 7 Conclusion…………………………….…...………………………1032622684 bytesapplication/pdfen-US無線區域網路柴比雪夫低通濾波器頻率校正WLANchebyshevlowpass filtertuningthesishttp://ntur.lib.ntu.edu.tw/bitstream/246246/57476/1/ntu-94-R92943118-1.pdf