Progress of Transmission Technologies for UDTV

This paper describes the recent progress of research and development on transmission technologies for Super Hi-Vision (SHV), which is the form of ultrahigh-definition television (UHDTV) with the highest resolution class. The paper covers the transmission systems for SHV program production and satellite broadcasting. For short-haul transmission, an optical digital interface for video equipment was developed. It wavelength-multiplexes eight 10-Gb/s optical signals. It was experimentally confirmed that the transmission distance was at least 2 km, and that a series connection of the interfaces did not severely deteriorate jitter performance. We are also developing a 120-GHz-band wireless contribution short-haul link consisting of three transmitter/receiver pairs. All three pairs transmit and receive a 10.3-Gb/s signal at the same frequency. Experiments showed that transmission with little crosstalk is possible over a distance of 1.25 km when the receiver spacing is 8 m. A long-haul optical contribution link that we developed can transmit a 24-Gb/s SHV signal over a distance of 260 km by using optical amplifiers and no electronic repeaters. An IP network would be a good choice for long-distance links such as an international live contribution link. Several live IP transmissions of compressed video were conducted. Satellite relay transmission and broadcasting technology is also being developed. In particular, we have developed a QPSK/8PSK wide-band modem that uses LDPC and BCH codes. The modem could transmit 251-Mb/s (QPSK) and 677-Mb/s (8PSK) signals and was used in a live SHV satellite-transmission experiment.