Skip to main content

Updating ATSC Standard Could Put an End to Manual Channel Rescans

(Image credit: Gary Arlen)

WASHINGTON—As the three-year channel repack comes to an end next month, viewers of over-the-air television in certain markets will (once again) have to rescan their TVs to locate the new positions of local ATSC 1.0 channels. This is how it has been through Phases 1-9 and will be so in the final Phase 10.

Does it have to be that way in the new era of ATSC 3.0? ATSC doesn’t think so. In a blog on nabpilot.org, ATSC Chair and NAB Senior Vice President of Technology Lynn Claudy says that, with the deployment of ATSC 3.0 coinciding with the end of the channel repack, updating the 3.0 standard to allow for automated rescan updates could bring an end to this manual and tedious process. 

PLUS: Repack Heads Into the Home Stretch

Currently, when broadcasters are moving to a new channel due to the repack, they are required to provide public notifications via broadcasts (channel crawls) and PSAs of such changes—and there are similar rules for stations providing such notifications to over-the-air viewers when they begin deploying ATSC 3.0. Such notices need to alert viewers of channel changes that—unlike the repack—don’t have deadlines set in stone.  

“We are now about to enter an era where there are no set dates for initially moving to NextGen TV and markets may add additional NextGen TV channels and further move ATSC 1.0 stations around on an unknown and continuing basis until some indeterminate time in the relatively far future when all broadcasting has finally transitioned entirely to NextGen TV,” Claudy said. “Every time there is a change in their market, consumers will need to remember to manually rescan their TV set, a process that can take up to several minutes, in a culture where we impatiently tap our foot in front of the microwave oven.”

There is a recommended practice for manufacturers of consumer electronics to provide software in today’s smart TV’s that periodically scans for new channels, however this process has not been widely adopted, according to Claudy.

An alternative would be to use a new part to the ATSC 3.0 standard, “ATSC Candidate Standard on Regional Service Availability," which was originally adopted as a Candidate Standard in 2018, and is currently being voted on by the ATSC membership to be elevated to a full Standard (A/200).

The candidate standard: “specifies information describing the availability of broadcast services over time within a broadcast region. Broadcast receivers may use this information to help construct a list of services that may be available to them. Additionally, the information provides a schedule that allows receivers to maintain an up-to-date service list. This document describes how the information may be distributed using either an ATSC 1.0 broadcast (or any MPEG-2 transport stream), ATSC 3.0 broadcast or over broadband.”

Most importantly, the standard would use an XML specification of a “Regional Service Availability Table” (RSAT) that would provide information specific to localities, including schedules and channel information for new ATSC 3.0 services being launched. 

PLUS: NextGen TV Marks Vegas Debut

“Once this information is available to a receiver that has been designed to receive RSATs and reconfigure its channel information appropriately, the need for manual rescanning by consumers would be largely or completely obviated,” Claudy said.

Using channel crawls or PSA’s to notify viewers of channel changes is so 20th century. This new candidate standard would help remove one more chore that viewers would need to remember, Claudy said. 

“Smarter infrastructure that extends the intelligence of TVs to keeping track of basic program information on their own would go a long way in again making television technology ‘fit in so that you don’t really even notice it,’” he said.