Turbo Equalization with Parametric Uncertainties: Comparison of SNR Estimation Algorithms
نویسندگان
چکیده
We consider turbo equalization of ISI channels for the practically relevant case when neither channel state information nor SNR knowledge is perfect at the receive side. In particular, we investigate the influence of imperfect (uncertain) training information on the performance of several known SNR estimation algorithms. Numerical results indicate that uncertain training data causes an additional bias that may lead to a performance degradation. We propose a modified, adaptive SNR estimation algorithm with reduced bias in the low SNR regime.
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