2014 年 12 巻 ists29 号 p. Tj_1-Tj_6
This paper presents the requirement specifications for an output filter for a 21-GHz band broadcasting satellite system and shows simulation results of the characteristics of the filter. The proposed 21-GHz band broadcasting satellite system is applied to a wideband single carrier transmission using bandwidth of approximately 300 MHz and an array-fed reflector antenna for power control to countervail attenuation due to rainfall. The power radiated to the rainy area is boosted intensively by a beam forming network. Therefore, a satellite transponder has multiple output routes, and each route is equipped with an output filter. Considering this system, the output filter was designed for a linear frequency response and low in-band group delay, and sufficient suppression of interference from adjacent bands such as the radio astronomy band. We evaluated the electrical characteristics by computer simulation; low-loss and low-group delay deviation in the satellite broadcasting band and sufficient attenuation in the radio astronomy band were confirmed.
