Then, we grasp the target and the direction of the research. Finally, the thorough analysis of the generic system model of Spread Spectrum(SS) and Improved Spread Spectrum(ISS) modulation has been done.

• 并对扩频技术(Spread Spectrum，SS)的数字水印一般模型以及ISS(Improved Spread Spectrum，ISS)调制关键技术进行了深入分析。