在本篇論文中，我們利用兩種不同的架構設計並且實作了一個應用於無線通訊，且具有低功率以及高線性度特性的四階巴特渥斯轉導電容低通濾波器，第一種較為常見的架構使用無損耗式積分器作為濾波器的建構方塊，而第二種架構中我們提出了利用損耗式積分器來設計濾波器的作法。為了提升濾波器的線性度，本篇論文介紹了一個具有高線性度之轉導放大器，另外，利用多重輸入的轉導放大器設計，可以大幅減少整個濾波器所需要的功率消耗以及晶片面積。最後，由於轉導電容濾波器的頻寬可以藉由調整轉導放大器的轉導值來作調整，本設計中亦加上了一個離線式頻寬調整系統來克服由於晶片製程變異所產生的頻寬不準確性。
　　為了驗證所提出的濾波器設計，採用了TSMC 0.18_μm CMOS製程製作了兩個實驗晶片，所需的電源供應為1.8伏特。量測的結果指出，使用無損耗式積分器作為建構方塊之濾波器其頻寬由原先設計的10 MHz下降至8.8 MHz，直流增益則為 -0.74 dB，當輸入訊號頻率是1 MHz且大小為1.5 Vppd時，其總諧波失真小於 -40 dBc。另外，濾波器的功率消耗大約是5.5 mW。
　　根據模擬結果，使用損耗式積分器建構之濾波器其線性度表現較使用無損耗式積分器為佳，當輸入訊號頻率是1 MHz且大小為1.9 Vppd時，其總諧波失真小於 -40 dBc。同時，使用損耗式積分器之濾波器其功率消耗只有大約4 mW。除此之外，當啟用離線式頻寬調整系統時，其頻寬調整的誤差小於5%。

In this thesis, a 4th-order Butterworth Gm-C filter with low power consumption and high linearity performance for wireless communication applications is designed and implemented in two different structures: common lossless-integrator-based structure and novel lossy-integrator-based one. To increase the linearity of the filter, an operational transconductance amplifier (OTA) with high linearity is introduced. Furthermore, the multi-input OTA structure is employed to reduce the power consumption and the active area. Due to the adjustability of the OTA transconductance, an offline frequency tuning system is also added to overcome the bandwidth inaccuracy which is caused by the process variation.
In order to evaluate the performances of the designed filters, two test chips are fabricated with TSMC 0.18_μm CMOS process and the supply voltage is 1.8 V. The measurement results of the lossless-integrator-based 4th-order filter show that the filter bandwidth is varied from 10 MHz to 8.8 MHz and the DC gain is about -0.74 dB. The total harmonic distortion (THD) is smaller than -40 dBc when the input signal frequency is 1 MHz and the amplitude is less than 1.5 Vppd. Besides, the power consumption of the filter is about 5.5 mW.
According to simulation results, the lossy-integrator-based 4th-order filter has better linearity performance than the lossless-integrator-based one. Its THD is smaller than -40 dBc when the input signal frequency is 1 MHz and the amplitude is less than 1.9 Vppd. Moreover, the power consumption of the lossy-integrator-based 4th-order filter is only 4 mW. By enabling the offline tuning loop, the frequency tuning error is less than 5%.

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