前饋式可調式寬頻雙取樣4-4 MASH帶通差和調變器設計

THE DESIGN OF A WIDEBAND TUNABLE DOUBLE-SAMPLED FEEDFORWARD 4-4 MASH BANDPASS DELTA-SIGMA MODULATOR

黃億永(Yi-Yung Huang)

指導教授 ： 黃淑絹

大同大學/電機資訊學院/電機工程學系所/碩士(2008年)

摘要

帶通差和調變器已經廣泛被運用在射頻通訊系統及測量儀器的製造，主要是因為帶通差和調變器比傳統的Nyquist-rate轉換器更能達到較高的解析能力。隨著無線通訊協定的增加，在寬頻和多模的射頻/中頻接收器中，需要設計可調整和有彈性的調變器。
本篇論文提出的可調雙取樣前饋式多級雜訊整形帶通差和調變器，可依照所需的頻寬調整參數，使用前饋式架構的優點，除了可降低操作放大器非理想效應的影響，還可簡化多級雜訊整形的複雜度，而雙取樣的技術可以輕易的增加取樣頻率並減低對放大器的需求。此4-4 MASH帶通調變器的設計流程是先使用MATLAB模擬理想之系統層級電路，得到最佳化的參數值後，用HSPICE模擬電路層級的電路，最後再用CADENCE將整個電路在實體層畫出來。此電路是用TSMC 0.18μm CMOS 1P6M製程參數進行模擬。

關鍵字

可調式 ； 帶通差和調變器 ； 雙取樣

並列摘要

Bandpass delta-sigma converters have been widely used in RF communication systems and instrumentation filed due to the ability to obtain high resolution in the band of interest compared to the traditional Nyquist-rate converters. As the growing of the wireless communication standards, the demand for a wideband and multi-stand RF/IF receivers has led the design of the modulators to be tunable and flexible.
This thesis proposes a tunable double-sampled feedforward multi-stage noise shape (MASH) delta-sigma modulator. It will tune according to the demand bandwith. The advantages of feedforward topology are reducing the non-idea effect of the opamp and decreasing the complexity of the design for the MASH architecture. Additionally, double-sampled switch-capacitor (SC) technique provides a good method of increasing the sampling frequency and relaxes the requirement of the opamp. The design flow corresponding to the CAD tools is as following. Using MATLAB, the optimal parameters are obtained by the system level simulation. Then, the circuit level simulation is implemented by HSPICE. Finally, the layout of the whole circuit is accomplished with Virtuoso of CADENCE. And the modulator is simulated by using the SPICE models of TSMC 0.18μm CMOS 1P6M process.

並列關鍵字

DELTA-SIGMA MODULATOR ； DOUBLE-SAMPLED ； TUNABLE

參考文獻

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