ATSC 3.0 in Smartphones Involves ‘Significant Technical Challenges,’ Motorola Tells FCC

The cellular OEM singled out for mention in its letter the May 9 comments from the Advanced TV Broadcasting Alliance of low-power TV interests, urging the FCC to require 3.0 reception in smartphones when 3.0 broadcasts are available to at least 25 percent of the U.S. population. Motorola also cited June 8 replies from Free Access & Broadcast Telemedia backing the alliance's call for 3.0 tuner mandates, Though One Media is promoting 3.0 functionality in smartphones through a voluntary, market-driven approach rather than through mandates, its efforts drew the ire of T-Mobile, which accused the Sinclair subsidiary of oversimplifying the challenges of building 3.0-capable smartphones (see 1709120020). One Media struck back in a rebuttal letter Wednesday in which it said the carrier doesn't like competition and the market-driven approach means T-Mobile need not sell 3.0 smartphones if it doesn't want to.

Mandating 3.0 smartphone functionality “without regard to consumer demand is not in the public interest,” and would involve “significant technical challenges and limitations,” said Motorola. “While equipment manufacturers routinely face tradeoffs in developing products, they should be resolved to meet customer demand, not dictated by government fiat.” Alliance and FAB Telemedia representatives didn’t comment.

Physics “limits available antenna performance in a mobile device,” and “available antenna performance in mobile devices is already fully exploited to support cellular service,” said Motorola, making the technical case against a 3.0 smartphone mandate. Adding a 3.0 receiver to a smartphone also would “substantially hurt cellular performance,” because it would “require extending the operation of one of the smartphone’s internal cellular antennas to cover additional TV frequencies down to 470 MHz,” it said. The “asynchronous nature” of cellular and TV frequencies means “doing so would require simultaneous operation of the cellular modem and the ATSC 3.0 receiver,” it said. The LTE signal degradation that would result when the smartphone is tuned to 3.0 “would devastate a customer’s cellular experience,” it said.

Since a smartphone’s antenna would be shared between the cellular transceiver and the 3.0 receiver, “substantial additional RF front end diplexing and filtering circuitry would be required to separate the two signals and to assure acceptably low interference between them,” said Motorola. “It is not feasible to add ATSC 3.0 to a smartphone without impacting its industrial design significantly.”

Building 3.0 receivers into smartphones “should be market-driven,” said Motorola. “Unless and until there is substantial consumer demand for ATSC 3.0-capable smartphones, manufacturers should not be expected to devote the resources and incur the costs associated with attempting to overcome the technological issues and negative design impacts” of building such devices, it said.

Even if consumers were to begin clamoring for 3.0-capable smartphones, designing them would require features “that American consumers likely would view as undesirable,” said Motorola. OEMs, including Motorola, have developed devices that incorporate DTV receivers in markets outside the U.S. where there's strong demand for broadcast TV reception in mobile phones, it said. To overcome the technical “limitations” of doing so requires building a “relatively large, dedicated external antenna for DTV, and a dedicated internal RF front end and DTV receiver system that can operate independently of the cellular transceiver,” it said.

Adding large external antennas “has a very obvious and negative impact on the size and industrial design of the smartphone, to which U.S. consumers of premium-tier devices would react negatively,” Motorola said. “The external antenna and internal components necessary for broadcast TV reception increase the cost of a smartphone, which consumers may find unpalatable.”

As for One Media’s T-Moblle rebuttal letter, the carrier’s technical white paper accusing Sinclair of oversimplifying the challenges of building 3.0 into smartphones was a “red herring,” said the filing. No broadcaster “to our knowledge has advocated for a tuner mandate in fixed or mobile devices,” said One Media. In actuality, low-power TV interests, through the Advanced TV Broadcasting Alliance, asked the FCC to impose a 3.0 tuner mandate on fixed TV devices within a year of releasing its order and on mobile devices when 3.0 broadcasts reach at least 25 percent of the U.S. population. “Nothing mandates that T-Mobile incorporate Next Gen TV capabilities in devices designed for T-Mobile’s customers,” said One Media. “If T-Mobile doesn’t want to compete, it does not have to.”

One Media doesn’t deny the “complexity” of building 3.0 reception into smartphones, but thinks it’s a “challenge worth pursuing.” One Media thinks public safety and emergency information delivery “is vastly enhanced on a broadcast platform,” contrary to T-Mobile’s allegations that 3.0 will be an “inferior” emergency alerting platform. “Competition is a good thing,” and the FCC “should skeptically view” T-Mobile’s white paper “for what it is: a self-serving, protectionist attempt to prevent new entrants from competing in the mobile video marketplace,” said One Media. If the “mobile opportunities” for 3.0 “are sufficiently compelling,” as One Media thinks they will be, “then the marketplace will respond accordingly,” it said. “If T-Mobile does not want to participate, it doesn’t have to.” T-Mobile representatives didn’t comment Wednesday.