Apparatus and method for producing periodic synchronization references

Abstract

An apparatus, such as an adaptive flywheel, and method for producing periodic time references, forming a periodic time reference signal, from uncertain time references. A counter counts from a first count value to a second count value and provides a periodic time reference each time its count reaches the second count value. An error processing device, coupled to the counter, determines (a) whether an uncertain time reference is received within a predetermined range of count values (corresponding to a window of expectation), or (b) whether the absolute value of the average of an error, corresponding to the number of increment values before or after the second count value, whichever is lower, the count is at when an uncertain synchronization reference is received, and at least one previously determined error for at least one previously received uncertain synchronization reference is greater than WC/2 increment values. The error processing device causes the counter to reset the count to the first count value when, with respect to (a), an uncertain time reference is received when the count is at a count value other than one in the range of predetermined count values, and with respect to (b), the absolute value of the average error is greater than a predetermined number of (i.e., WC2) increment values.