Frequency tracking which adapts to timing synchronization

A frequency tracking apparatus configured to dynamically track frequencies in a wireless communications network, comprising:

• a correlation mechanism configured to calculate a frequency offset associated with a data symbol received during a symbol period by performing a correlation exclusively between a plurality of samples of the data symbol received during the symbol period;
• and
• a frequency control window determination unit configured to determine the plurality of samples from the data symbol received during the symbol period to be used in calculating the frequency offset, wherein the frequency control window determination unit receives data indicating a timing offset and the plurality of samples is based on the timing offset, wherein the timing offset indicates a change in symbol boundary,
• wherein a number of samples used to calculate the frequency offset is determined based, at least in part, on the timing offset.

A method for determining a frequency offset at a wireless communications receiver, wherein the receiver receives an OFDM symbol during a time period, comprising the steps of:

• receiving data indicating a timing offset associated with the OFDM symbol, wherein the timing offset corresponds to a detected change in symbol boundary;
• choosing a number of a plurality of samples from the OFDM symbol received during the time period based, at least in part, on the timing offset;
• and
• performing a cross-correlation operation exclusively between the chosen number of the plurality of samples of the OFDM symbol received during the time period to determine a frequency offset associated with the OFDM symbol.

A non-transitory computer readable storage media containing a set of instructions for a processor to perform a method of determining a frequency offset at a wireless communications receiver, comprising:

• a routine to receive data indicating a timing offset associated with a data symbol received during a time period, wherein the timing offset indicates a change in symbol boundary;
• a routine to choose a number of a plurality of samples from the data symbol received during the time period based, at least in part, on the timing offset;
• and
• a routine to perform a cross-correlation operation exclusively using the chosen number of the plurality of samples of the data symbol received during the time period to determine the frequency offset.

A frequency error estimator, comprising:

• means for receiving data indicating a timing offset associated with a data symbol received during a time period, wherein the timing offset indicates a change in symbol boundary;
• means for choosing a number of a plurality of samples from the data symbol received during the time period based, at least in part, on the timing offset;
• and
• means for performing a cross-correlation operation exclusively using the chosen number of the plurality of samples of the data symbol received during the time period to determine the frequency offset.