Frequency-domain turbo equalization, including multi-mode adaptive linear equalization, adaptive decision-directed channel estimation, adaptive noise variance estimation, and dynamic iteration control

摘要

Frequency domain based methods and systems to perform adaptive multi-mode pre-decoding linear equalization, adaptive channel estimation, turbo equalization, turbo equalization iteration control, and noise variance estimation. An adaptive linear pre-decoder equalizer may include a multi-mode equalizer, which may include a blind equalizer to determine initial equalization coefficients and a decision-directed equalizer to refine the initial equalization coefficients. Turbo equalization may include a dynamic iteration termination criterion and/or a fixed termination criterion. Turbo equalization may be based in part on an adaptive estimated noise variance. Methods and systems disclosed herein may be implemented with respect to single-carrier signals such as digital video broadcast signals.