Effect of depolarization on dual-polarized satellite link with 16- and 32-ary modulation schemes

At present, the needs of satellite broadcasting are extending. Since we must meet the needs, we want to enrich the quality of satellite broadcasting. And the transmission quantity should increase, so the technology of high capacity transmission needs more progress. On the other hand, the information transmission using a radio wave is progressing too except the field of the satellite broadcasting. Also we should consider the effective utilization of a frequency spectrum. Then, we want to use a more high frequency band that is uncultivated. Because of this situation, 21GHz-band and 42GHz-band were assigned internationally as future frequency bands for satellite broadcasting. These are shown in Table.1. Regarding the increasing transmission quantity, we should remark “dual polarized satellite broadcasting system” and “multi-level modulation method”. If we can use the technology effectively at the same time, the transmission quantity becomes several times as much. And if these can be applied on those bands, rapidly increasing of this quantity can be realized. But we will have some demerits too. For example, those are large rain attenuation, noise, and cross polarization interference. They degrade link characteristics. Then purpose of this research is assessing effect of these factors quantitatively.