That standard was supposed to expire this year, but “as no party is ready to adopt a new standard,” the FCC said, it was retained with the commissioners believing that it “remains essential at this time for protecting both innovators and investors in the 3.0 space, allowing stakeholders to develop and purchase equipment with confidence.”

The A/322 Standard describes the RF/Transmission of a physical layer waveform, AKA, the over-the-air RF signal. This waveform enables flexible configurations of physical layer resources to target a variety of operating modes.

“In ATSC 1.0 (A/53) it is the 8VSB signal that occupies the 6MHz RF channel,” said Joe Turbolski, Vice President of Sales & Marketing at Hitachi-Comark.

“In ATSC 3.0, it can be adjusted with different modulation/coding schemes available in the A/322 standard.”

The intent is to signal the applied technologies and allow for future technology adaptation.

“Within the ATSC 3.0 standard there is the bootstrap signal (System Discovery and Signaling),” said Turbolski. “The bootstrap is always the same configuration and basically defines the remainder of the data being broadcast so that the receiver knows what is about to be received and can properly decode the signal. So if legacy receivers are not able to decode newer technologies in the years to come, the bootstrap tells those legacy receivers to just ignore the data that they cannot decode and focus on the data that can be decoded.”

Developers of ATSC 3.0 want to be able to update the standard without FCC approval in the future but, until July 17, 2027, the current standard will remain in place.

As to the variety of operating modes, ATSC 3.0 allows the broadcaster to utilize multiple physical layer pipes (PLP’s), each specifically configured for an operating mode or use case. “So for Non-Real-Time data delivery (NRT), the PLP can be minimized in terms of data rate, modulation, and code rate, you don’t necessarily need a huge data pipe for NRT data,” said Turbolski. “For linear HDTV, the PLP can be configured for higher data rate, higher SNR similar to what is used in ATSC 1.0, perfect for fixed indoor or roof mounted TV antenna. For mobile/handheld use case, the PLP can be configured with a much more robust signal that can deal with very low SNR requirements and combat the effects of doppler (car driving down the highway).”

In other rulings, the FCC extended through July 17, 2027, the rule that required that “lighthouse” signals be “substantially similar” to the primary video stream of the ATSC 3.0 signal. That rule had been set to expire this year, but the agency said it believes that viewers need more time to be guaranteed that they can watch the same programming they watch today whether or not they have a TV that can receive the ATSC 3.0 “NextGen TV” signals.

The FCC wants to preserve these multicast streams from a lighthouse station which has converted to ATSC 3.0 and are aired on a “host” station still broadcasting in the current ATSC 1.0 transmission system; so that viewers without NextGen TV-compatible televisions can continue to receive their favorite TV programming.

Among other things, the modified rules clarify that the originating station (and not the host station) is responsible for regulatory compliance for the multicast lighthouse stream being aired on the host station, and they give the Commission clear enforcement authority over the originating station in the event of a rule violation on the hosted multicast programming stream.