Advanced Digital HDTV - Advanced Television Research Consortium (Sarnoff, Thomson, Philips, NBC and CLI)
Advanced Digital HDTV introduced the concepts of a layered digital system design, adapting MPEG-1 compression for television's interlaced scanning and organizing data into a flexible packetized data transport. It used two QAM carriers, one having higher power to achieve a more robust transmission. Compressed video data was "partitioned" so that the most important video data and audio could be placed in "high priority" packets and sent on the higher power carrier. This rudimentary approach foreshadowed the scalable coding and multiple PLP capabilities of the ATSC 3.0 standard.
AD-HDTV System Description (1992) | AD-HDTV System Layers diagram
- Fun Fact: DirecTV launched with a data packet format that was a modification of the AD-HDTV system.
- Fun Fact - the MPEG-2 transport standard came about because Sarnoff, Thomson and Philips took the concept into MPEG for standardization. The MPEG-2 packet format still has the header bit from AD-HDTV that indicates if it is a "High Priority" packet.
1989 - 1990 Advanced Digital HDTV System Origins
The process to develop AD-HDTV sought out the best technical approaches to video compression and RF transmission from research labs around the world, including Sarnoff, Thomson (Los Angeles, Hannover and Rennes) and Philips (Briarcliff, Eindhoven and Paris) . There were seven projects on video data compression and three projects on digital data transmission that were tested and evaluated to pick the best approaches (see AD-HDTV Prologue page)
July 7, 1990 - Progress Report to Erich Geiger (Reitmeier) reports parallel efforts underway at Sarnoff and Briarcliff to find the
best technical approaches. There are seven projects on video data compression and three projects on digital data transmission
July 13, 1990 - Digital Hierarchy data packet concept (Reitmeier) articulates the concept of scalable coding
Oct 10, 1990 - ATRC Digital Simulcast Report to Wiley (Reitmeier) outlines ATRC vision and approach for a digital simulcast system
1991 - Advanced Digital HDTV System
As Advanced Digital HDTV (AD-HDTV) gains momentum and is obviously the preferred long-term approach. ATRC begins to position its Advanced Compatible Television (ACTV) system as an immediate solution until a practical digital HDTV can be introduced in the future.
Jan 04, 1991 - PR planning for NAB messaging begins (Gray)
Jan 04, 1991 - Advanced Digital Television 1991 project plan presentation (Reitmeier)
Jan 30, 1991 -- NAB preparations begin
Feb 12, 1991 - Digital TV OSI Layers chart
Feb 5, 1991 - ADTV Progress Report summarizes project accomplishments
"... During the past six months, the concept of digital HDTV has moved from a few small technology development activities to a major development program. Setting the stage for this transition were advances in both data compression and RF transmission that showed the basic feasibility of a digital approach. In RF transmission, two independent efforts (at Sarnoff and Thomson-LER) showed that data rates on the order of 20-30 Mbps could be transmitted in the 6 MHz broadcast channel. In data compression, independent computer simulations (at Sarnoff, Philips-Briarcliff, TCE-LA, TCE-Hannover, and Philips-Paris) showed that both DCT-based and SubBand-based compression approaches could achieve HDTV picture quality within the bit rate of the RF transmission. By August 1990, it became clear that digital was the right way to achieve HDTV..."
Feb 06, 1991 - Rationale for ADTV white paper explains fundamental system design principles
Feb 27, 1991 - ADTV Pre-Certification System Description is submitted to ACATS
March 21, 1991 - ADTV system pre-certification presentation to ACATS (known as "hellweek") - Reitmeier
March 26, 1991 - Response to questions from ACATS SS-WP1 committee members
April 1991 - ADTV system presentation at NAB 91 (Reitmeier, Basile) | ADTV System Overview paper (Reitmeier, Basile)
April 1991 - AD-HDTV and ACTV at NAB 91
NAB 91 was the first public demonstration of simulated picture clips from the AD-HDTV system. Advanced Compatible Television (ACTV) remained the primary focus of the ATRC
May - Sept 1991 - AD-HDTV enters the harware design phase. It is a massive "moon shot" effort to design a prototype implementation for what was probably the most complex television system that had ever been conceived at the time.
See AD-HDTV Prototype Design page
AD-HDTV Prototype Hardware Design
1992 AD-HDTV System Integration and Testing
Jan 31, 1992 - ATRC press release AD-HDTV certified for testing
Feb 18, 1992 - ATRC plan to enlist computer industry support for AD-HDTV
April 1992 - AD-HDTV at NAB 92
NAB 92 unleashed a tremendously competitive set of booths and demonstrations, as the competing proponent systems
April 1992 - "Introducing AD-HDTV" NAB92 Brochure
AD-HDTV at the Advanced Television Test Center
The system was tested extensively from June through September 1992.
First HDTV - NTSC Simulcast at WRC-TV
1992 – After completing its testing, ATRC demonstrates the world’s first simulcast of analog NTSC TV and digital HDT, at NBC's WRC-TV station in Washington, featuring WRC's live news and up- and down-conversion between high definition and standard definition. This was the precedent for the industry's subsequent analog to digital transition.
Proposed System Improvements
Nov 1992 – After its test results are released, system improvements are proposed to demonstrate more system flexibility in the prototype hardware and to correct performance issues encountered in testing.
Dec 21, 1992 - ATRC internal status report
AD-HDTV at NBC
Jan 1993 – After its demonstration of simulcasting, ATRC moves AD-HDTV to NBC headquarters at 30 Rock to perform intergration tests with digital VCRs.
The ACATS Special Panel
The preparation for the Advisory Committee's Special Panel was intense. Each proponents was out to win and made their best case
ATRC assesment of AD-HDTV vs. competing digital systems | ATRC introductory remarks to the Special Panel (Reitmeier)
Feb 1993 – The ACATS Advisory Committee “Special Panel” convened to review test results and select the winning system. It concludes that the digital systems are superior to analog proposals, but it fails to select a winner among the four competing digital systems
Back to: Competing Digital Systems