Frequency correction of a radio module. Multiple samples of frequency data
are taken during a quiescent portion of the base station transmission, to estimate
the amount of frequency correction needed. An embodiment applies the frequency
data to a median filter to eliminate invalid data. Next, a new reference frequency
is applied to a radio transceiver in the radio module to provide the frequency
correction. If the frequency was corrected by greater than a pre-determined amount,
the process performs a large shift frequency correction, including verifying that
the first frequency correction was satisfactory and verifying that the radio transceiver
is able to receive data after the frequency correction has been performed. If the
frequency was corrected by smaller than a pre-determined amount, the process performs
a small shift frequency correction, including updating a total of all frequency
corrections made since a stored reference frequency was updated.
