6CORDESSES L. A tool for periodic wave generation[J]. Single Processing Magazine, 2004,21 (5): 110-112.
7LIU X D, SHI Y Y, WANG M, et al. Direct digital frequency synthesizer based on curve approximation[J]. Industry Technology, 2008,21:1-4.
8STROLLO D DE CARO A G M. Direct digital frequency synthesizers exploiting piecewise linear chebyshev approximation[J]. Micro electronics Journal, 2003,34:1099- 1106.
9IZOUGGAGHEN B, KHOUAS A, SAVARIA Y. Spurs modeling in direct digital period synthesizers related to phase accumulator truncation [J]. Circuit and System, 2004,23(3):89-92.