Abstract: In one embodiment, an improvement is described for synchronization between devices in, e.g., a wireless network, wherein at least one device includes both a slow clock and a fast clock for different modes of operation. The fast clock for an active mode of operation is calibrated after a sleep mode of operation during which the slow clock is employed for device timing. Calibration employs a filter-based technique. Counts for the slow clock and for the fast clock are measured over a first interval, and the number of slow-clock counts is measured over a second interval. An estimate for the number of fast counts over the second interval is generated, filtered to reduce noise and error effects, and then employed to update the fast clock in the active mode of operation.

Abstract: In one embodiment, an improvement is described for synchronization between devices in, e.g., a wireless network, wherein at least one device includes both a slow clock and a fast clock for different modes of operation. The fast clock for an active mode of operation is calibrated after a sleep mode of operation during which the slow clock is employed for device timing. Calibration employs a filter-based technique. Counts for the slow clock and for the fast clock are measured over a first interval, and the number of slow-clock counts is measured over a second interval. An estimate for the number of fast counts over the second interval is generated, filtered to reduce noise and error effects, and then employed to update the fast clock in the active mode of operation.