FCC Likely to Release Notice as Next Step on Receiver Standards

FCC Chairman Julius Genachowski discussed receiver standards at a Silicon Flatirons conference Monday (CD Feb 14 p1) and during a press conference after the FCC meeting. “This process has revealed issues around receivers,” he said Wednesday. “Addressing them will require a concerted effort."

One FCC official said the vast number of receivers already in use means the FCC faces a tough task: “The cat is already out of the bag.” A second official said the legacy issue is complicated, but trying to devise a solution covering different performance standards for different functions and different receivers will also be difficult.

"I think there is a lot of interest, given the growing pressure to find more spectrum,” said Public Knowledge Legal Director Harold Feld. Setting receiver standards is one way of ‘finding’ more spectrum by enhancing efficiency. It also provides greater certainty for folks trying to innovate within the service rules. If you know the nature of receivers in neighboring services, you can better avoid interference.” The issue is about more than just LightSquared, Feld said. “This problem keeps coming up,” he said. “The trick is balancing cost for equipment manufacture, which increases with interference standards, and deployed legacy equipment with the efficiency gains. This is one of many places where everyone in the spectrum ecosystem -- licensees, equipment manufacturers, users -- will need to figure out how we can share the pain in a rational way that makes more spectrum available for all our needs."

"It’s very difficult to draw up coherent receiver standards without knowing what kinds of transmissions receivers need immunity from,” said Information Technology Innovation Foundation Senior Fellow Richard Bennett. “One source of interference is strictly power related: relatively high power transmissions adjacent to a band with low power, as in the case of the LightSquared 4G network adjacent to GPS. The GPS receivers need to be engineered to reject the high-power signal, which they can certainly do, but only do by incorporating circuitry that they didn’t need when they were originally built. This is the analog engineering problem of receiver saturation. The other interference problem is in the digital domain. This kind of interference occurs when receivers have to choose between signals from multiple transmitters that are easily confused with each other, and it has to be solved for things like high power unlicensed networks to work well."

The FCC historically has failed to make progress on receiver standards “because there are so many kinds of interference from so many sources that a receiver needs to reject that it’s impossible to create a universal test to verify compliance,” Bennett said. “To make progress on the issue, they will need to narrow the scope of the kinds of interference that receivers need to reject to a testable set of characteristics."

Free State Foundation President Randolph May said he would prefer to see the FCC focus on market-based solutions rather than new rules. “I understand the impulse behind the notion that the commission should adopt receiver standards as a means of ‘finding’ more spectrum,” May said. “With due respect to the engineers, such an undertaking would be exceedingly difficult because of all the variables. More fundamentally, while setting receiver standards may be cast as an issue that can be resolved through ’technical’ expertise, realistically, like much of the Commission’s work, the effort is likely to become ‘political’ because the costs involved in compliance will impact different parties in different ways, depending on how the standard is set."

"Adopting comprehensive receiver standards may be a lengthy and difficult process, but the FCC has to take on the task,” said Free Press Policy Director Matt Wood. “Incumbent users shouldn’t be able to sideline their potential competitors or new innovative products. No matter how important an existing service may be, we can’t let current users exercise a veto over advances in neighboring spectrum bands."

In March 2003, the FCC launched a notice of inquiry on receiver standards under then Chairman Michael Powell (CD March 14/03 p1). The inquiry asked for comments on such issues as “immunity performance and interference tolerance of existing receivers,” whether immunity levels can be improved and “potential positive and negative impacts of receiver standards on innovation and the marketplace.”

The notice built on one recommendation of the Spectrum Policy Task Force, which issued a report Nov. 15, 2002. The FCC “should consider applying receiver performance requirements for some bands and services, either through incentives, regulatory mandates, or some combination of incentives and mandates,” the report said (http://xrl.us/bhji9u). “With the coming advances in technology, the Task Force does not believe that minimum receiver performance requirements would necessarily stifle innovation. In the future it is expected that, to a considerable extent, interference problems will be eliminated or adequately mitigated by flexible software solutions built into the receiver; for example, software-controlled filter responses.”

But the task force recommendation ran into substantial opposition, especially from carriers. “Market forces have proven to be more than adequate to ensure efficient and effective use of CMRS spectrum and ... receiver requirements could have the contrary effect of impinging on competition and limiting the introduction of new innovative uses,” CTIA said. In May 2007, then Chairman Kevin Martin circulated an order formally ending the inquiry (CD May 4/07 p2).