The Development of Demodulator for Data Collection Platforms (DCP) in Himawari Ground Station

摘要

We developed a new demodulator (DCP DEM) for Data Collection Platforms (DCP) systems, which is to be incorporated into the new ground system required to operate the new next geostationary meteorological satellite Homeward-8/9. The DCP DEM receives and demodulates the DCP signal transmitted through the satellite from DCP modulators (DCP MOD) scattered over wide area including outside of Japan. The total number of the frequency channels used in DCP MOD is 133. A transmission frequency channel and a transmission period are assigned to each DCP MOD. Then, the circuit size of demodulation increases because DCP DEM has to demodulate all of the received data for 133 channels at the same time. We could reduce the size of the DCP DEM by designing to demodulate the received data for multi channels in one demodulator board. Since Ka-Band is used as down-link frequency in the new Himawari DCP system, higher phase noise causes performance loss in demodulation. To mitigate the degradation of demodulation performance due to phase noise, we proposed novel methods in this paper. The performance of the developed demodulator is evaluated in this paper.