3Kroupa V F. Spectral properties of DDFS. Computer simulations and experimental verifications[C] //IEEE international Frequency Control Symposium, [ s. l. ] : IEEE Press, 1994:613 - 623.
4Mattison E M, Coyle L M. Phase noise in direct digital synthesizers [ C ]//42^nd Annual Frequency Control Symposium. MA: Baltimore, 1988:352 - 356.
