We consider high complexity and long delay of the code-aided carrier synchronization algorithm at low SNR(signal to noise ratio). We use the estimation integrator for compensating signal vector and decreasing offset to be estimated. A new iterative synchronization stopping rule is proposed. The system will stop iteration if the mean of the absolute values of LLR (log-likelihood ratio) message at the output of LDPC decoder keeps steady. The simulation results indicate that this algorithm narrows the frequency search range and the average number of iterations is reduced greatly. It also shows that the performance loss is not larger then 0.12 dB.
SHEN Hai-Ou
,
WANG Yong-Min
,
XU Hua
,
HAN Bo
,
LI Peng
. A complexity-reduced iterative carrier synchronization algorithm[J]. Journal of University of Chinese Academy of Sciences, 2013
, 30(5)
: 694
-698
.
DOI: 10.7523/j.issn.2095-6134.2013.05.019
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