Decision feedback channel estimation and pilot tracking for OFDM systems

摘要

Current OFDM systems use a limited number of symbols and/or sub-channels to provide approximations for channel estimations and pilot tracking, i.e. phase estimations. For example, two training symbols in the preamble of a data packet are used to provide channel estimation. Four of the fifty-four sub-channels are reserved for providing phase estimation. However, noise and other imperfections can cause errors in both of these estimations, thereby degrading system performance. Advantageously, decision feedback mechanisms can be provided to significantly improve channel estimation and pilot tracking in OFDM systems. The decision feedback mechanisms can use data symbols in the data packet to improve channel estimation as well as data sub-channels to improve pilot tracking.