A 4th-order active-Gm-RC low-pass filter with RC time constant auto-tuning for reconfigurable wireless receivers

Author

Liu Junbo ; Fan Xiangning ; Bao Kuan

Author_Institution

Sch. of Inf. Sci. & Eng., Southeast Univ., Nanjing, China

fYear

2012

fDate

Oct. 29 2012-Nov. 1 2012

Firstpage

1

Lastpage

3

Abstract

Based on 0.18μm RF CMOS process, a 4th-order Butterworth low-pass filter (LPF) used in reconfigurable wireless receivers (for WCDMA and GPS/Galileo) is presented in this paper. The LPF adopts active-Gm-RC structure, and can satisfy both WCDMA and GPS/Galileo requirements, which maximizes hardware reuse. A RC time constant auto-tuning circuit is applied to improve the accuracy of bandwidth. The chip area occupies 0.78mm². The LPF is measured on wafer. With 1.8V power supply, the core circuit of the LPF consumes 1mW and 1.6 mW for WCDMA and GPS/Galileo respectively. The out of band attenuation rate is about -78dB/10 octave. The measured 1dB compression point is severally -3.0dBm and -5.1dBm.

Keywords

Butterworth filters; CMOS analogue integrated circuits; Global Positioning System; circuit tuning; code division multiple access; low-pass filters; radio receivers; 4th-order Butterworth active-Gm-RC low-pass filter; GPS-Galileo requirement; LPF; RC time constant autotuning circuit; RF CMOS process; WCDMA requirement; power 1 mW; power 1.6 mW; reconfigurable wireless receivers; size 0.18 mum; voltage 1.8 V; Filtering theory; Global Positioning System; Low pass filters; Multiaccess communication; Spread spectrum communication; Switches; Tuning;

fLanguage

English

Publisher

ieee

Conference_Titel

Solid-State and Integrated Circuit Technology (ICSICT), 2012 IEEE 11th International Conference on

Conference_Location

Xi´an

Print_ISBN

978-1-4673-2474-8

Type

conf

DOI

10.1109/ICSICT.2012.6467693

Filename

6467693