Advancing the Digital HDTV Grand Alliance System from the Test Laboratory to the Real World

Abstract

Digital advanced television in the United States is now moving from the testing phase into the implementation phase. Testing of the digital HDTV Grand Alliance System by the Advanced Television Test Center (ATTC) was completed in July 1995. The system performed well compared to the six systems tested previously, in terms of picture and sound quality and transmission robustness, and it met or exceeded virtually all of the performance targets established by the Federal Communications Commission (FCC) Advisory Committee on Advanced Television Service (ACATS). Although the testing process provided sufficient data to warrant recommendation of the system for adoption by the FCC, and it was proven well-suited to the terrestrial broadcast environment in the United States, several issues related to spectrum planning and RF implementation were not completely addressed in the ACATS testing. Since that time, ATTC and its successor organization, the Advanced Television Technology Center, have been conducting additional testing to address these issues. — The U. S. Advanced Television Systems Committee documented the Grand Alliance System as the ATSC Digital Television Standard, released in September 1995. In November 1995, the system was formally recommended to the FCC, which then incorporated the ATSC Standard in its Notice of Proposed Rule Making on Advanced Television, issued in May 1996. — Meanwhile, as the rule-making process moves forward, the FCC is awarding licenses for experimental HDTV stations. In April of this year, the industry-supported Model HDTV Station Project was announced. In July, the Project was licensed to operate an experimental station as WHD-TV, which first broadcast on July 30. The Project is sponsored by the Association for Maximum Service Television (MSTV) and the Consumer Electronics Manufacturers Association (CEMA), a sector of the Electronic Industries Association (EIA). The three-year project is funded by some 250 television stations and 16 equipment manufacturers. Among the member stations are both of the other stations that have received experimental licenses from the FCC. The host facility is WRC-TV, the NBC owned-and-operated station in Washington, DC. The Model HDTV Station Project will provide a “real-world” environment in which broadcasters and manufacturers can work together to evaluate a wide range of studio, transmission, and receiving equipment, to conduct propagation and coverage experiments, and to obtain practical training and experience in building and operating an HDTV station.