摘要 |
A method is disclosed for correcting carrier frequency offset (CFO) in a received data packet that includes one or more M data streams. The data packet has a payload portion preceded by a preamble portion, the payload portion having a plurality of data symbols (L) each of which include a plurality of data tones (K). The method comprises, making a per-stream preamble CFO estimate for each data stream by correlating repeated preamble portions that precede the data packet. The per-stream preamble CFO estimates are weighted and averaged to obtain a single preamble CFO estimate. Any CFO in each received data stream is then corrected according to the preamble CFO estimate. Additionally, for an lth data symbol in a data packet, a per-tone CFO estimate is derived and successively averaged over frequency (tones), time (symbols) and space (data steams) to derive data CFO estimate pdata. Any CFO in each received data stream may be corrected according to the data CFO estimate, and/or the preamble CFO estimate.
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