1994 年 18 巻 21 号 p. 31-35
This paper analyzed the perfomance of the hierarchical modulation scheme for 20 GHZ digital HDTV broadcasting satellite system in the presence of the rain fall attenuation. And this paper clarified an optimum power assignment ratio to maximize the spectrum efficiency. The paper also clarified an another optimum power assignment ratio to maximize the signal-to-noise power ratio.