22 October 1993 Joint blind equalization, carrier recovery, and timing recovery for HDTV modem
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Proceedings Volume 2094, Visual Communications and Image Processing '93; (1993) https://doi.org/10.1117/12.157894
Event: Visual Communications and Image Processing '93, 1993, Cambridge, MA, United States
Abstract
We introduce a high speed modem structure based on an adaptive blind equalization coupled with carrier and timing recovery for QAM-based HDTV modem receiver. The adaptive equalization, which is called a modified `stop-and-go' algorithm (MSGA), uses the combination of the constant modulus algorithm (CMA) and a `stop-and-go' algorithm (SGA). The CMA initializes the equalizer coefficients; once initialized, the CMA is switched to the MSGA for completing equalizer convergence. In order to obtain faster convergence, the Sato- like errors used in the SGA are replaced by errors used for updating coefficients in the CMA. The carrier recovery for coupling with the adaptive equalization uses the decision-directed technique. The calculation of absolute sum of error gives a simple and reliable way of switching from CMA to MSGA for the adaptive equalizer's coefficient updating procedure. The nonlinear spectral line extraction scheme, which consists of a prefilter and a squarer followed by a narrow bandpass filter, is used for the timing recovery. In timing recovery scheme, we propose a zero-crossing detection technique for extracting the exact symbol timing phase from the output of the narrow bandpass filter output. Simulation results reveal that the proposed structure is robust against additive white Gaussian, impulsive noise, multipaths and carrier phase errors such as frequency offset, phase offset and phase jitter.
© (1993) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Yong-Seok Choi, Yong-Seok Choi, Deok Soo Han, Deok Soo Han, Hyun Ha Hwang, Hyun Ha Hwang, } "Joint blind equalization, carrier recovery, and timing recovery for HDTV modem", Proc. SPIE 2094, Visual Communications and Image Processing '93, (22 October 1993); doi: 10.1117/12.157894; https://doi.org/10.1117/12.157894
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