Computer Science and Information Engineering, World Congress on (2009)

Los Angeles, California USA

Mar. 31, 2009 to Apr. 2, 2009

ISBN: 978-0-7695-3507-4

pp: 181-185

DOI Bookmark: http://doi.ieeecomputersociety.org/10.1109/CSIE.2009.451

ABSTRACT

A simplified nonlinear least square (NLS) carrier frequency offset (CFO) estimation scheme is proposed based on an OFDM training symbol with L identical parts. Since the NLS CFO estimate scheme has no close-solution, the estimate process is divided into two steps of fine and coarse estimations. The fine estimation is obtained by the correlation of two identical halves in the training symbol. After compensating the fine estimation, the coarse estimation is easily obtained based on NLS by searching the peak on the L-point frequency grids.Moreover, to reduce the computational complexity of coarse CFO estimation, a strategy of adaptive adjusting the number of used sub-symbols based on estimate reliability evaluation is devised. Computer simulations demonstrate that the proposed CFO estimator has a satisfying estimate performance, while maintaining a low computer complexity.

INDEX TERMS

frequency offset estimation, OFDM, identical parts, nonlinear least square

CITATION

Wen Chen,
Yun Wu,
Wu-Jun Xu,
"A Simplified NLS Frequency OffsetÂ Â Estimator for OFDM Systems",

*Computer Science and Information Engineering, World Congress on*, vol. 01, no. , pp. 181-185, 2009, doi:10.1109/CSIE.2009.451