A direct digital frequency synthesis system for low power communications

This work describes a direct digital frequency synthesis (DDFS) architecture based on nonlinear interpolation for signal generation in mobile communications systems such as Bluetooth. DDFS is capable of well controlled, rapid changes in frequency, over a relatively large frequency range, however a conventional DDFS system requires a power hungry ROM. To avoid this problem a ROM-less architecture with a low power nonlinear interpolation DAC is proposed. This system is robust to parameter variations and consumes only 5mW at 100MHz.