Fractional multimodulus prescaler

摘要

A prescaler is used for generating an output frequency from an input frequency by fractional division. It comprises a component signal composer (402) arranged to generate a number of parallel component signals that differ in phase from each other. Additionally it comprises a controllable phase selector (403) arranged to respond to a control signal by either selecting a constant number of unchanged ones of the parallel component signals or to repeatedly change its selection among the parallel component signals. The component signal composer (402) is arranged to generate more than four parallel component signals for the phase selector (403) to choose from.