Title :
Joint estimation of carrier and sampling frequency offset for OFDM systems in slow fading channel
Author :
Zhonghua Sun ; Lan Yu ; Chaoxi Ren
Author_Institution :
Aeronaut. Training Base, Naval Aeronaut. Eng. Inst., Qingdao, China
Abstract :
This paper proposes a pilot-assisted joint estimation algorithm of carrier frequency offset (CFO) and sampling frequency offset (SFO) in orthogonal frequency-division multiplexing (OFDM) systems based on a slow fading channel. The proposed algorithm firstly completes the coarse estimation of fractional carrier frequency offset (FCFO) by researching the phase relation of neighboring pilots in time-domain, and then reduces the interchannel interference (ICI) markedly by compensating the received signal in time-domain. At last, the fine estimation of FCFO and SFO is implemented by comparing the phase shifts of different sub-carriers in neighboring pilots. By using the average as the final estimating value, the Influence of noise is reduced and the estimation accuracy of the CFO and SFO is increased. Theoretical analysis and simulation results for multi-path channel show that the proposed algorithm has higher estimation accuracy and needs less pilot symbol than the existing similar methods.
Keywords :
OFDM modulation; adjacent channel interference; fading channels; frequency estimation; multipath channels; time-domain analysis; FCFO; ICI; OFDM systems; SFO; coarse estimation; estimation accuracy; final estimating value; fractional carrier frequency offset; interchannel interference; multipath channel; neighboring pilots; orthogonal frequency-division multiplexing systems; phase relation; phase shifts; pilot symbol; pilot-assisted joint estimation algorithm; received signal; sampling frequency offset; slow fading channel; time-domain; OFDM; carrier frequency offset; joint estimation; sampling frequency offset;
Conference_Titel :
Communication Technology (ICCT), 2012 IEEE 14th International Conference on
Conference_Location :
Chengdu
Print_ISBN :
978-1-4673-2100-6
DOI :
10.1109/ICCT.2012.6511205