An iterative soft decision directed linear timing estimator

The paper addresses the issue of estimating the symbol timing in turbo receivers. We propose a linear timing estimator which benefits from the soft information delivered by the turbo system at each iteration to compute the timing estimate. This estimator is then compared to a synchronizer based on the expectation-maximization (EM) algorithm (Herzet, C. et al., ICASSP, 2003). Performance of the proposed synchronizer is illustrated by simulation results and proves better than that of the EM-based counterpart regarding both convergence speed and range.

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