Maximum likelihood block decision feedback estimation for CCK demodulation apparatus and method

摘要

A maximum likelihood CCK detector has a first subtractor which subtracts the contents of a pre-equalize register from a current symbol, and the output of this subtractor is coupled to a simple Fast Walsh Transform (FWT) with an iteration variable k. The output of the FWT is coupled to a second subtractor for subtracting a plurality of ICI corrections for all possible current symbols computed from the post-FWT domain value of the current CCK symbol and stored in post equalization registers. A post equalization register contains values computed from feedback filter coefficients determined during a packet preamble, where the feedback filter coefficients are provided to a reduced complexity post equalization value generator which populates the post equalization register using an iteration variable i.