Analysis of DDS Technique and Implementation of Eliminating Noise

An important frequency synthesis technology with such advantages as high frequency resolution and fast frequency conversion, DDS has found wide application in radar, Acoustic Doppler Current Profiler (ADCP) and communication field. Theory analysis unveils that the compact relations between the noise and reference periods. The less the noise, the higher the reference frequency. The results imply that the created wave will be distorted when the ratio of the reference clock to its frequency is less than 10:1. Moreover, a practical, simplified and robust method on how to design butterworth filter for suppressing glitches according to the noise of DDS is introduced with a CMOS Chip of AD9854.