Fox is going to shift program distribution of all its broadcast and cable networks to an entirely high-definition system under a multi-million dollar deal with Motorola, becoming the first major U.S. programmer to make such a move.
The new satellite transmission system, which includes Motorola encoders, encryption and control software, and satellite receivers, will be rolled out to the Fox broadcast network, national cable channels, regional sports networks, Fox News Channel and Fox Business Network starting in the first quarter of 2009.
“This is a huge project for us which has essentially been four years in the making,” says Andrew Setos, president of engineering for Fox. “We’re replacing the entire distribution infrastructure of the company, and at the same time, we’re achieving tremendous bandwidth efficiencies."
A key to Fox’s plan are satellite receivers (also known as radios) for cable headends which can take a high-definition signal and automatically down-convert it for standard-definition distribution. That will allow Fox to send a single high-definition program feed for each network (excluding multiple regional feeds for some networks) instead of having to maintain the dual high-definition and standard-definition feeds it transmits today.
“We came to the conclusion a couple years ago, that TV really is HDTV,” says Setos. “And just like the transition from black and white to color, eventually you don’t have separate facilities any longer.”
Deployment of the Motorola MPEG-2 based system, which will replace existing Tandberg HD encoding gear, will continue through 2010, with new encoders and receivers gradually being rolled out across all the Fox broadcast and cable networks.
“Everything is gradual,” says Setos. “You don’t deploy 20,000 devices overnight. Both will start at the same time, and the broadcast network will be done and using it by the next football season [Sept. 2009]. On the cable side, we’ll finish all the regional sports networks by the end of 2009, and the rest of everything else by 2010.”
The Fox engineering team spent over a year evaluating several compression vendors, with Motorola getting the nod based on a number of factors, including not only technology but pricing, delivery schedules and service guarantees. Fox will use Motorola’s SE-3000 high-end HD encoders (which cost in the $30,000 to $40,000 range) to compress its programming, and will transmit them via satellite using DVB-S2 advanced modulation.
The higher bit rates afforded by DVB-S2, which can deliver a payload of up to 73 megabits per second in a 36 megahertz transponder, will allow Fox to deliver a bit-rate-efficient statistical multiplex of four HD feeds on a single transponder.
“That’s literally double the efficiency we’re achieving right now,” says Setos. “We have 13 transponders in this architecture, and we’re essentially creating another 13 transponders in terms of the capacity of feeds.”
The payload gains of DVB-S2 modulation is part of the reason why Fox is sticking with MPEG-2 compression for its program distribution instead of going to MPEG-4 advanced compression, which has been adopted by cable programmers like HBO and Starz for HD distribution to cable headends because of its 50% improvement in bit-rate efficiency over MPEG-2.
Since DVB-S2 lets Fox meet its HD needs within its existing satellite capacity, and the end product for both the broadcast and cable networks still needs to be delivered in MPEG-2 to serve the existing universe of HDTV sets and digital cable set-tops, Fox decided it would avoid any potential impact in quality that might result from transcoding a signal from MPEG-4 to MPEG-2.
Setos notes, however, that the radios Fox is buying could still support MPEG-4 in the future, if Fox elects to go that way.
“The radio is future-proof, and would work with either MPEG-2 or MPEG-4,” says Setos. “We haven’t poured the concrete on just MPEG-2.”
Despite the rapid growth of HD programming over the past two years, the majority of cable subscribers are still watching standard-definition television. So the Motorola DSR-6000 digital satellite radios that Fox will provide its cable affiliates include the capability to derive an SD version of the HD content transmitted by Fox.
They will also read the Active Format Descriptor (AFD) information carried with the HD content which specifies how the images will be displayed on 4:3 aspect ratio standard-definition sets, i.e. in either letter-boxed format or 4:3 center-cut with sidebars. Fox, along with NBC Universal, PBS and station groups Hearst-Argyle, Tribune and Cox Broadcasting, has been a strong supporter of using AFD to display downconverted programming in the correct aspect ratio.
Fox is still evaluating vendors for new MPEG-2 “splicer” devices which local broadcast affiliates will use to insert local content, such as commercials and branding, into the MPEG-2 compressed HD feed. Fox broadcast affiliates have been using splicers built by Terayon and integrated by Thomson since Fox’s 2004 HD launch, and will retain those units as redundant backups. The new splicers will have some important new features, such as giving stations the ability to do an EAS (Emergency Alert System) crawl without having to downconvert the video to standard-definition.
Motorola deployed its first MPEG-2 HD encoders with HBO in 1999. Motorola executives say its compression technology has come a long way since then, with particular improvement in statistically multiplexing HD signals. While Fox is the first major U.S. programmer to consolidate its program distribution to a single HD system, Motorola executives expect that other networks will follow Fox’s lead.
“I think there are a lot of opportunities,” says Mark Schaffer, director of product management for Motorola. “This is the first customer we’ve dealt with to make that move, and we certainly hope it’s not the last.”
