Compensation of IQ imbalance and transmitter nonlinearities in broadband MIMO-OFDM

Author

Gregorio, F. ; Cousseau, J. ; Werner, S. ; Riihonen, T. ; Wichman, R.

Author_Institution

Dept. of Electr. & Comput. Eng., Univ. Nac. del Sur, Bahia Blanca, Argentina

fYear

2011

fDate

15-18 May 2011

Firstpage

2393

Lastpage

2396

Abstract

Predistortion techniques are implemented in OFDM systems to improve power amplifier efficiency while keeping in-band and out- of-band distortion at acceptable levels. Predistorter (PD) design for broadband MIMO-OFDM systems introduces several implementation challenges. Coupling effects cannot be avoided in MIMO transceivers where the paths are implemented on the same chipset. Moreover, baseband PDs are affected by imbalances in the IQ modulator. This paper proposes a MIMO-PD that linearizes the power amplifier (PA) response and compensates for both crosstalk and IQ imbalance. Error vector magnitude (EVM) and adjacent channel power ratio (ACPR) results show a significant improvement compared with conventional PD systems.

Keywords

MIMO communication; OFDM modulation; broadband networks; crosstalk; power amplifiers; radio transmitters; wireless channels; IQ imbalance; IQ modulator; MIMO transceiver; MIMO-PD system; OFDM system; adjacent channel power ratio; broadband MIMO-OFDM system; coupling effect; error vector magnitude; in-band distortion; out-of-band distortion; power amplifier efficiency; power amplifier response; predistorter design; predistortion technique; transmitter nonlinearity; Couplings; Crosstalk; MIMO; Noise; OFDM; Polynomials; Transmitters;

fLanguage

English

Publisher

ieee

Conference_Titel

Circuits and Systems (ISCAS), 2011 IEEE International Symposium on

Conference_Location

Rio de Janeiro

ISSN

0271-4302

Print_ISBN

978-1-4244-9473-6

Electronic_ISBN

0271-4302

Type

conf

DOI

10.1109/ISCAS.2011.5938085

Filename

5938085