NON-LINEAR TIME DOMAIN CHANNEL ESTIMATION IN OFDM SYSTEMS

摘要

An OFDM receiver generates an initial channel impulse response in response to a received OFDM signal. The receiver determines the time span within the initial channel impulse response in which significant paths are present. An intermediate channel impulse response estimator identifies paths within the initial channel impulse response and generates an improved intermediate channel impulse response. A channel impulse response estimator performs a second non-linear process to generate a channel impulse response. An equalizer responds to the channel impulse response and the OFDM symbol to equalize the OFDM symbol. Metrics are generated that can be used for effectively stopping the second iterative non-linear process.

主权项

1. An OFDM receiver comprising:
an initial channel impulse response estimator that generates an initial channel impulse response having a number of samples in response to a received signal having one or more OFDM symbols; a time segment selector that selects a subset of samples from the initial channel impulse response as the subset of samples for analysis of an intermediate channel impulse response; an intermediate channel impulse response estimator that identifies paths within the subset of samples from the initial channel impulse response and generates an improved intermediate channel impulse response in a first non-linear process; a channel impulse response estimator responsive to the intermediate channel impulse response estimator that performs a second non-linear process to generate a channel impulse response; and an equalizer responsive to the channel impulse response and the OFDM symbol to generate an equalized OFDM symbol.