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BS digital broadcasting (ISDB-S), there is a 17% improve-ment in frequency usage eciency. Further, ISDB-S3 adopts APSK modulation schemes. It is possible to secure trans-mission capacity of approximately 100 Mbps when 16-APSK (code rate: 7/9) is used. is allows for an 8K transmission on one channel for 12 GHz band satellite (occupied bandwidth of 34.5 MHz).Concerning the standards for the transport layer, MPEG-H MMT was introduced to realize broadcasting-communication services. We give the results of the trans-mission performance on the physical layer and of the syncing functionality on the transport layer as below.2.2MMT signal and testing compositione syncing mechanism by MMT is shown in Fig. 1. On the transmitter side, transmission is made with a pre-sentation timestamp (PTS) attached that takes into account transmission and processing delays. On the receiver side, synced transmission is achieved by comparing the coordi-nated universal time (UTC) obtained from the NTP server with the PTS time before displaying the video.e composition of the WINDS satellite transmission testing is shown in Fig. 2. e verication objective of the testing is to time syncretize two programs received from dierent lines, so we used two types of uplink device: large earth terminal (LET) and very small aperture terminal (VSAT). On the LET side, a 4K signal is transmitted simul-FiF1　Mechanism for syncingVSATUTCtimeUTCtimeUTCtimeMainvideoTransmissiondelayΔtd1MainvideoSecondaryvideoTransmissiondelayΔtd2Processing delayΔtp1SecondaryvideoProcessing delayΔtp2PTS =Ts+ΔtoffsetPTS = Ts+ΔtoffsetTransmitsatTsPresentation ofTs+ΔtoffsetPresentation ofTs+ΔtoffsetΔtoffsetBuffertime(Δtoffset-Δtd2-Δtp2)Receiver 1MMTtransmitterReceiver2TsTsTsLET(Δtoffset-Δtd1-Δtp1)Buffer timeFiF2　Composition of WINDS satellite transmission testing (ISDB-S3)MMTStreamerISDB-S3Tx#1ISDB-S3Tx#2ISDB-S3Rx#1ISDB-S3Rx#1LETVSATLETMMT(4K HEVC)MMT(2K HEVC)3-GHz IF3-GHz IF3-GHz IF4K HEVC2K HEVC2KDisplay28.03-GHz18.27-GHz1-GHz IFMMT(4K HEVC)MMT(2K HEVC)SpectrumAnalyzerWINDSD/CDividerNoise TestBERcounterMMTRx #1MMTRx #228.07-GHzU/CU/C140-MHz140-MHz18.23-GHzVSAT lineLET line4KDisplaySynchronizationVariabledelay3 Ultra-High-Speed Satellite Communication Technology120　　　Journal of the National Institute of Information and Communications Technology Vol. 64 No. 2 (2017)