Quadrature direct digital frequency synthesis using fine-grain angle rotation

This paper presents an area- and power-efficient quadrature direct digital frequency synthesis technique called fine-grain angle rotation. To reduce the large bit-width requirement of the angle rotation, multiple start points are introduced and the angle rotation is applied to the small angle remained. A prototype chip occupies 0.16 mm/sup 2/ in 0.25 /spl mu/m 1P5M CMOS technology and consumes 90 mW at 400 MHz clock frequency, which is significantly improved performance compared to the previous state-of-the-art chips.