A low spurious level fractional-N frequency divider based on a DDS-like phase accumulation operation

This paper presents a novel architecture of a low spurious level fractional-N frequency divider. It has already been shown in previous work that the use of a direct digital synthesizer (DDS) represents a promising solution to the mitigation of the fractional spurs that appear at the output of fractional frequency dividers, but with the drawback of causing a non-linear control of the division ratio. The DDS-based architecture proposed in this paper recovers the benefit of having a linear tuning of the division ratio, while still having similar performance in terms of fractional spurs.