Improved channel estimation in OFDM systems in the presence of CFO

Author

Oliver, J. ; Aravind, R. ; Prabhu, K.M.M.

Author_Institution

Dept. of Electr. Eng., Indian Inst. of Technol. Madras, Chennai, India

fYear

2009

fDate

8-10 Oct. 2009

Firstpage

398

Lastpage

401

Abstract

We consider the problem of pilot-aided accurate least squares (LS) channel estimation in the presence of carrier frequency offset (CFO). We first formulate the mean square error (MSE) of the LS channel estimator in the presence of CFO and then show how to select the pilot sequence (with element values constrained to plus or minus one) that minimizes the MSE. Our main conclusion is that, in the presence of CFO accurate channel estimates can be obtained by transmitting identical pilot symbol on all subcarriers. We demonstrate our results via computer simulations.

Keywords

OFDM modulation; channel estimation; least squares approximations; mean square error methods; CFO; OFDM systems; carrier frequency offset; computer simulations; improved channel estimation; mean square error; orthogonal frequency division multiplexing; pilot-aided accurate least square channel estimation; Bit error rate; Bit rate; Channel estimation; Fading; Frequency estimation; Interference; Least squares approximation; Mean square error methods; OFDM modulation; Partial transmit sequences; Carrier frequency offset (CFO); Channel estimation (CE); Intercarrier interference (ICI); Least squares (LS); Mean square error (MSE);

fLanguage

English

Publisher

ieee

Conference_Titel

Communications, 2009. APCC 2009. 15th Asia-Pacific Conference on

Conference_Location

Shanghai

Print_ISBN

978-1-4244-4784-8

Electronic_ISBN

978-1-4244-4785-5

Type

conf

DOI

10.1109/APCC.2009.5375609

Filename

5375609