Method and apparatus for eliminating the effects of frequency offsets in a digital communication system

A method used in a communication system including a first transceiver unit and a second transceiver unit disposed remotely from the first transceiver unit, the second transceiver unit operable to communicate in a bi-direction manner for direct exchange of information with the first transceiver unit, the method comprising:

• detecting a sampling frequency offset between a first sampling frequency used by the first transceiver unit to transmit a first signal and a second sampling frequency used by the second transceiver unit to receive the first signal, by comparing a first digital signal produced by digitally sampling the first signal at the second sampling frequency to the received first signal detected by the second transceiver unit;
• and
• adjusting sampling points of data to be transmitted by the second transceiver unit in response to detecting the sampling frequency offset, wherein an error associated with the sampling frequency offset is reduced.

A device adapted to be used in a first unit that communicates with a second unit using a common sampling frequency, the device comprising:

• a delay lock loop that is coupled to receive digitally sampled data of a first signal transmitted by the second unit, and digitally detected data of the first signal, the delay lock loop being adapted to detect a sampling frequency offset in the first signal in response to the digitally sampled data of the first signal and the digitally detected data of the first signal, and to produce offset information corresponding thereto;
• and
• a first digital low-pass filter that is coupled to receive the offset information and data to be transmitted by the first unit in a second signal to be received by the second unit, the first digital low-pass filter being adapted to digitally interpolate the data to be transmitted in accordance with the common sampling frequency and the sampling frequency offset wherein an error associated with the sampling frequency offset is reduced.