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of 150-1,000 Mbps, using transmission materials and Super High Vision (SHV) that NHK has developed.e result of this experiment is introduced in 3-6 of this report.④ Dynamic demand assign experimentWe verify the technology of dynamic slot assignment according to user association, not based on a planned slot assignment.It is necessary to rewrite soware of the onboard baseband switch of WINDS. We conrmed operability in a ground test using soware upload evaluation apparatus.⑤ Experiment of verifying health of APAAis experiment has been continuously performed since the initial checkout phase aer the launch by JAXA and NICT. We check the health of APAA elements by a rotating-element electric-eld vector method.e results of this experiment are introduced in 3-7 of this report.⑥ Airborne communication experimentWe will develop the airborne earth station and verity the establishment of broadband links that enable transmis-sion of large-volume data such as Pi-SAR observation data.e result of this experiment is introduced in 3-8 of this report.⑦ Experiment of transmission of Ka band multi-level modulation codeis experiment is performed under an agreement between JAXA and NICT. We will perform the fundamen-tal experiment to understand the eect of variation of characteristics of the transmission line such as non-linear-ity and rainfall attenuation in transmission of multi-level digital modulation code such as QPSK, 16 QAM, 16 APSK and 64 QAM, etc., and discuss countermeasures.e result of this experiment is introduced in 3-9 of this report.⑧ Seaborne communication experimentese days, technology of investigating marine re-sources has been developed and a system that enables real-time transmission of observation data taken by Remotely Operated Vehicle (ROV) and tele-operation of ROV from an on-shore base and a system to transmit the observation data obtained by Autonomous Underwater Vehicles (AUV) from Autonomous Surface Vehicles (ASV) to Research Vessel (RV) or an on-shore base have been designed.We are developing high-speed satellite communication devices that can be mounted on RV and ASV and that enable an antenna to track a satellite automatically to es-tablish stable satellite communication links. A remote ac-cess system is installed in the earth terminal in which ASV is equipped to enable unmanned operation to implement power management and emergent o-the-air, etc.We will perform verication of tracking performance, satellite line establishment and transmission characteristics by seaborne communication experiments at a data rate range from several Mbps to several tens of Mbps between vessels on the sea or between a vessel and a land station using these earth stations.e result of this experiment is introduced in 3-10 of this report.4ConclusionWINDS was launched on February 23, 2008, and has been used for experiments of various satellite communica-tion.e satellite shied to the Post-operation phase since April in 2013 and NICT planned Post-operation phase fundamental experiments. Here, we introduced the Fundamental experiments in the post-operation phase plan such as verication of the Fully-automatic transportable station function.Although nine years have passed since the launch, we will continue to implement the Fundamental experiments in the post-operation phases.ReferenceR1“Special Issue on Wideband InterNetworking engineering test and Demonstration Satellite (WINDS),” Journal of the National Institute of Information and Communications Technology, vol.54, no.4, Dec. 20072Takashi Takahashi, Naoko Yoshimura, Akira Akaishi, Norihiko Katayama, Morio Toyoshima, Naoto Kadowaki, Shojiro Ishibashi, Tatsuya Fukuda, and Hiroshi Yoshida, “THE TELE-OPERATION EXPERIMET OF THE HYBRID REMOTELY OPERATED VEHICLE USING SATELLITE LINK,” 34th International Conference on Ocean, Offshore and Arctic Engineering, OMAE2015-41645.3Amane Miura, Maki Akioka, Takashi Takahashi, Norio Komiyama, Yuichi Yamaguchi, and Masayoshi Yoneda, “Development of Channelizer for Disaster Satellite Communication System and Communication Experiment Using WINDS Satellite,” IEICE Technical Report, vol.114, no.27, SAT2014-10, pp.51–56, May 2014.Takashi TAKAHASHI Associate Director, Space Communications Laboratory, Wireless Networks Research CenterSatellite communication3 Ultra-High-Speed Satellite Communication Technology74　　　Journal of the National Institute of Information and Communications Technology Vol. 64 No. 2 (2017)