SYSTEMS AND METHODS FOR ADVANCED ITERATIVE DECODING AND CHANNEL ESTIMATION OF CONCATENATED CODING SYSTEMS

摘要

Systems and methods for decoding block and concatenated codes are provided, including channel state information estimation such as by using optimum filter lengths based on channel selectivity and adaptive decision-directed channel estimation. These improvements enhance the performance of various communication systems and consumer electronics, including HD Radio receivers and systems.

主权项

1. A method for iterative channel response estimation in a receiver of a multicarrier communication system that relies on forward-error-correction decoding, the method comprising:
selecting filter lengths for time and frequency domain channel estimation based on estimated time selectivity and frequency selectivity of said channel response, wherein said time selectivity and frequency selectivity are estimated using at least one of known pilot symbols and unknown data symbols; estimating said channel response using said selected filter lengths by using available pilot symbols and a first set of data symbols, the first set of data symbols being selected as a fraction of data symbols that are more reliable than a remaining fraction of data symbols in a second set of data symbols; with respect to symbol positions corresponding to said second set of data symbols, estimating the channel response by interpolation based on estimated values of channel response obtained from said pilot symbols and said first set of data symbols; performing forward-error-correction decoding using said channel response estimate to obtain improved estimates of coded bits; obtaining improved estimates of data symbols using said improved estimates of coded bits; calculating an updated channel response estimate using a shorter filter length for at least one filter and a larger fraction of said data symbols; and repeating the steps of performing forward-error-correction decoding and obtaining estimates of data symbols based on said updated channel response estimate, and calculating further updated channel response estimates based on improved estimates of data symbols.