Adaptive OFDM synchronization method using quadratic search step sizes

摘要

A system and method involve receiving a plurality of samples of at least one orthogonal frequency division multiplex (OFDM) signal, the samples containing at least one complete OFDM symbol including data samples and a cyclic prefix, using an initial symbol timing offset (STO) estimate to initialize an N×1 vector of occupation probabilities α, where Nis the number of sub-carriers of the OFDM signal, and, for each subsequent set m of OFDM samples received containing at least one complete OFDM symbol, determining a STO estimate from a set of candidate STO estimates, updating the vector of occupation probabilities α, and determining a final STO estimate. The final STO estimate is used to determine a carrier frequency offset and may be determined using the STO estimate with the highest occupation probability.

主权项

1. A method comprising the steps of:
receiving, at an antenna of a receiver system, a plurality of samples of at least one orthogonal frequency division multiplex (OFDM) signal, the samples containing at least one complete OFDM symbol including data samples and a cyclic prefix; using an analog-to-digital converter (ADC) operatively connected to the antenna to convert the samples of the OFDM signal into digital samples; using a processor operatively connected to the ADC to perform the steps of using an initial symbol timing offset (STO) estimate {circumflex over (θ)}0* to initialize an N×1 vector of occupation probabilities α, where N is the number of sub-carriers of the OFDM signal, for each subsequent set m of OFDM samples received containing at least one complete OFDM symbol, determining a STO estimate {circumflex over (θ)}m from a set of candidate STO estimates, updating the vector of occupation probabilities α, and determining a final STO estimate {circumflex over (θ)}m* , and removing the cyclic prefix from the OFDM symbol based upon the final STO estimate {circumflex over (θ)}m* .