Channel decoding apparatus and method in an orthogonal frequency division multiplexing system

摘要

A decoding apparatus and method in an OFDM (Orthogonal Frequency Division Multiplexing) communication system. In the OFDM system, a channel with a given frequency band is divided into a plurality of sub-channels spaced from one another in predetermined intervals, pilot symbols are transmitted on predetermined sub-channels, and data symbols are transmitted on the other sub-channels. A channel estimator generates a first channel estimate for each of the data symbols using the pilot symbols, a log likelihood ratio calculator calculates the reception probability of each information bit in the data symbol based on the first channel estimate, and a decoder generates the estimated probability values of the information bits based on the reception probability values of the information bits in the data symbol. Then, the channel estimator generates a second channel estimate for the data symbol based on the estimated probability values of information bits in the data symbol and updates the first channel estimate with the second channel estimate.