4Wang C C,She H C,Hu R. A Rom- less Direct Digital Frequency Synthesizer by Using Trigonometric Quadruple Angle Formola [J]. IEEE Solid - State Circuits, 2002, 38: 65 -68.
5Ayatollahi A,Jafari H. A Low Power, High SFDR, Romless Direet Digital Frequeney Synthesizer. IEEE International Frequency Cotrol Symposium and PDA Exhibition,2006: 654 - 661.
