Analysis and reduction of cross-modulation distortion in CDMA receivers

Author

Aparin, Vladimir ; Larson, Lawrence E.

Author_Institution

QUALCOMM Inc., San Diego, CA, USA

Volume

51

Issue

5

fYear

2003

fDate

5/1/2003 12:00:00 AM

Firstpage

1591

Lastpage

1602

Abstract

The jammer cross modulation (XM) transferred from a transmitter (TX) CDMA leakage by a receiver circuit is analyzed using the Volterra series and statistical theory. The measured "double-hump" XM spectrum is explained based on the CDMA signal statistics derived using the proposed system model of a reverse-link CDMA signal. The analysis shows that the XM distortion is affected by the circuit behavior not only at the jammer and the TX leakage frequencies, but also in the CDMA signal baseband and at the sum and difference of the excitation frequencies. This theory was verified on a 2-GHz Si bipolar junction transistor low-noise amplifier whose out-of-band terminations were optimally tuned to significantly reduce its XM distortion.

Keywords

UHF amplifiers; code division multiple access; jamming; modulation; nonlinear distortion; radio receivers; spectral analysis; statistical analysis; time-domain analysis; 2 GHz; CDMA receiver; CDMA signal baseband; CDMA signal statistics; Si; Si BJT LNA; Volterra series; bipolar junction transistor amplifier; cross modulation distortion; double-hump spectrum; jammer cross modulation; low-noise amplifier; optimally tuned out-of-band terminations; receiver circuit; reverse-link CDMA signal; statistical theory; system model; transmitter CDMA leakage; transmitter leakage frequencies; Baseband; Circuit analysis; Distortion measurement; Frequency; Jamming; Low-noise amplifiers; Multiaccess communication; Signal analysis; Statistics; Transmitters;

fLanguage

English

Journal_Title

Microwave Theory and Techniques, IEEE Transactions on

Publisher

ieee

ISSN

0018-9480

Type

jour

DOI

10.1109/TMTT.2003.810144

Filename

1196192