A ROM-less direct digital frequency synthesizer based on 16-segment parabolic polynomial interpolation

This paper presents a novel architecture for direct digital frequency synthesizer (DDFS) based on a modified parabolic polynomial interpolation method. A 16-segment parabolic polynomial interpolation is adopted to replace conventional ROM-based phase-to-amplitude conversion methods. Besides, the proposed parabolic polynomial interpolation is realized in a multiplier-less fashion such that the speed can be significantly improved. The proposed DDFS is implemented in a standard 0.13 mum cell-based technology. The maximum clock rate is 227 MHz, and the core area is 0.25 mm². The simulation result shows that the spurious free dynamic range (SFDR) is 117 dBc.