In the first mode of operation CFO estimations and corrections are done.
In this mode after the FCFO is estimated only OFDM symbols carrying the synchronization signals are corrected to make them usable to estimate ICFO.
After ICFO has been estimated it is added to FCFO and only symbols carrying the reference symbols are corrected to estimate RCFO.
This estimate is added to other two calculated estimates and the correction is done
for the first OFDM symbol. It is just to avoid extra multiplications and latency in the system.
The symbols are accessed in the same order as shown by numbered arrows in Fig. 5.