Design of optimal pilot-tones for channel estimation in MIMO-OFDM systems

Author

Wu, Zhongshan ; He, Jianqiang ; Gu, Guoxiang

Author_Institution

Dept. of Electr. Eng., Louisiana State Univ., Baton Rouge, LA, USA

Volume

1

fYear

2005

fDate

13-17 March 2005

Firstpage

12

Abstract

Orthogonal frequency division multiplexing (OFDM) systems empowered by multiple-antenna technology, known as MIMO-OFDM, have gained wide applications in high-rate wireless data communications. We focus on optimal channel estimation of MIMO-OFDM systems in this paper. A new method for pilot-tone design is presented that differs from existing work not only in its unique capability of estimating fast time-varying and frequency-selective fading channels, but also in the simplicity of its least square (LS) algorithm, free of matrix inversion. It is shown that the proposed new pilot-tones are actually orthogonal codes in the space-frequency domain, which achieve optimal channel estimation in the sense of obtaining the minimum mean square error (MSE) of channel estimation and thus inherit the same computational advantages as in the previous works. The design of the space-frequency codes (SFC) for a MIMO-OFDM system with any number of transmit antennas is studied and its effectiveness is demonstrated by computer simulations of a 2×2 MIMO system.

Keywords

MIMO systems; OFDM modulation; channel estimation; fading channels; least mean squares methods; space-time codes; time-varying channels; MIMO-OFDM systems; MSE; channel estimation; fast time-varying channels; frequency-selective fading channels; high-rate wireless data communications; minimum mean square error; multiple-antenna technology; optimal pilot-tone design; space-frequency domain orthogonal codes; Algorithm design and analysis; Channel estimation; Data communication; Design methodology; Frequency estimation; Frequency-selective fading channels; Least squares approximation; Mean square error methods; OFDM; Wireless communication;

fLanguage

English

Publisher

ieee

Conference_Titel

Wireless Communications and Networking Conference, 2005 IEEE

ISSN

1525-3511

Print_ISBN

0-7803-8966-2

Type

conf

DOI

10.1109/WCNC.2005.1424468

Filename

1424468