Device for estimating frequency offsets and method thereof

A device for estimating frequency offsets, performed by a wireless local area network system to periodically transmit a plurality of training signals, the device comprising a processor and computerized codes stored in a storage unit, the processor configured to execute the computerized code to perform a method, the method, comprising:

• receiving the plurality of training signals by a predetermined period;
• selecting selected training signals by a predetermined interval from the received training signals;
• detecting phases of the selected training signals;
• storing the detected phases of the selected training signals in the storage unit;
• reading the detected phases stored in the storage unit;
• averaging phase differences of every pair of the detected phases of the selected training signals;
• calculating the frequency offsets according to an average of the phase differences for every pair of the detected phases of the selected training signals;
• and
• calculating a weighted average of the calculated frequency offsets using weighting values for each of the calculated frequency offsets,
• wherein the weighting values are determined depending on a length of the predetermined intervals.