DDS中相位截断效应分析及其改善方法

An analysis of the output signals and a method to reduce the spurious phase accumulator truncation in DDS

分析了在直接数字频率合成（ＤＤＳ）中引起杂散的相位截断效应，针对其引起的杂散特点讨论了一种通过加入伪随机数改善杂散谱分布的方法，并通过计算机仿真进行了验证。

Spurious noise is one of problems in DDS, which has been researched in recent years.The paper analyses the signals as a result of the phase accumulator truncation. Then a method consistingof adding a sequence of pseudo-random numbers to convert the discrete line spurs into a continuous noisefloor is discussed. A computer program is created to verify this method.