Title :
A 20db, 250M CMOS Variable Gain Amplifier for GPS receiver
Author :
Li Xiao-qing ; Dong Li-min ; Peng Xiao-hong
Author_Institution :
VLSI & Syst. Lab., Beijing Univ. of Technol., Beijing, China
Abstract :
Variable Gain Amplifier (VGA) is a crucial part of GPS receiver, because the amplitude of RF signal changes greatly in transport. So a VGA is needed to fit the signal changing. This paper presents a VGA design based on the Gilbert unit. Implemented in a 0.18um CMOS process, the circuit achieved a gain range about 20dB from 18.39dB to 38.54dB, and reached a GBW=250MHz at 38db. The total current is about 8.87uA with a 3.3V supply. At same time, PGA (Programming Gain Amplifier) is explored for gain control realization, and an example is given to show how to realize the exponential control voltage for VGA.
Keywords :
CMOS integrated circuits; Global Positioning System; amplifiers; receivers; CMOS variable gain amplifier; GPS receiver; Gilbert unit; RF signal; VGA design; current 8.87 muA; frequency 250 MHz; gain control realization; noise figure 18.39 dB to 38.54 dB; programming gain amplifier; size 0.18 mum; voltage 3.3 V; CMOS integrated circuits; Electronics packaging; Gain; Gain control; Global Positioning System; Receivers; Voltage control;
Conference_Titel :
Microelectronics and Electronics (PrimeAsia), 2010 Asia Pacific Conference on Postgraduate Research in
Conference_Location :
Shanghai
Print_ISBN :
978-1-4244-6735-8
Electronic_ISBN :
978-1-4244-6736-5
DOI :
10.1109/PRIMEASIA.2010.5604911