The National Institute of Information and Communications Technology (NICT) has experimented using a 1,244 Mbps high-speed burst modem with single carrier QPSK modulation through a bandwidth of 1.1 GHz transponder on the Wideband InterNetworking engineering test and Demonstration Satellite (WINDS). We developed a 16APSK/16QAM-OFDM 3.2 Gbps radio frequency signal direct-processing transmitter and receiver system for even greater broadband transmission. This chapter shows that a 4K UHDTV transmission demonstration experiment using WINDS satellite bent-pipe transponder through a 10 GbE interface was successfully performed by this system.