A new method of TX leakage cancelation in W/CDMA and GPS receivers

Author

Aparin, Vladimir

Author_Institution

QUALCOMM Inc., San Diego, CA

fYear

2008

fDate

June 17 2008-April 17 2008

Firstpage

87

Lastpage

90

Abstract

The theory and practical implementation of a novel TX cancelation method in CDMA and GPS receivers are described. The method is similar to the continuous-time LMS algorithm, but uses the TX LO as the reference signal and low-pass filters instead of the integrators. The method was implemented as part of a 0.18 mum CMOS cellular-band receiver to cancel the TX leakage at the LNA input. The measured maximum rejection of the TX leakage is approximately 20 dB, the LNA NF is 1.8 dB, and the dc current consumption of the TX canceler is 4 mA.

Keywords

CMOS integrated circuits; Global Positioning System; cellular radio; code division multiple access; continuous time filters; least mean squares methods; low noise amplifiers; low-pass filters; radio receivers; wavelength division multiplexing; CMOS cellular-band receiver; GPS receivers; LNA; TX leakage cancelation; W/CDMA receivers; continuous-time LMS algorithm; dc current consumption; low-pass filters; reference signal; size 0.18 mum; Adaptive filters; Cellular phones; Degradation; Global Positioning System; Interference; Least squares approximation; Multiaccess communication; Pollution measurement; Radio frequency; SAW filters; Adaptive filters; MOSFET amplifiers; interference suppression; notch filters; receivers;

fLanguage

English

Publisher

ieee

Conference_Titel

Radio Frequency Integrated Circuits Symposium, 2008. RFIC 2008. IEEE

Conference_Location

Atlanta, GA

ISSN

1529-2517

Print_ISBN

978-1-4244-1808-4

Electronic_ISBN

1529-2517

Type

conf

DOI

10.1109/RFIC.2008.4561392

Filename

4561392