Regulators are mulling a
radio frequency receiver performance policy. The Federal Communications
Commission’s Office of Engineering and Technology has opened a comment period
on the elements of a receiver performance white
issued by its Technical Advisory Council in February.
The white paper focuses on defining interference limits as a means to creating
“This approach would make it easier to determine which party bears
responsibility for mitigating harmful interference when it occurs, by
specifying signal power levels called ‘harm-claim thresholds’ that a service
would be expected to tolerate from other services before a claim of harmful
interference could be made,” the commission’s Public Notice states.
Setting such harm-claim thresholds would avert the need to set receiver
performance standards, something the consumer electronics industry strenuously
opposes because of costs.
“Harm-claim thresholds provide incentives for operators to improve receiver
performance on a voluntary basis, whereas receiver mandates require
improvement,” the white paper says.
The commission is looking for feedback on specific points in the white paper as
well as the overall policy approach. It is asking if the harm-claim threshold
method is viable for all types of services across the spectrum and what should
be considered with regard to various coding and modulation schemes, for
Receiver performance efficacy is becoming more imperative as the spectrum
becomes more crowded with services, and the FCC finds itself in the position of
needing to change frequency usage designations. Such was the case with
LightSquared, the company that proposed building a 4G LTE wireless broadband
network on spectrum designated for satellite transmissions. LightSquared
secured a waiver of the rule limiting terrestrial transmissions on the
spectrum, but its plan was subsequently shot down when it could not demonstrate
that the network would not interfere with GPS devices operating in adjacent
spectrum. The company, in which investors had placed nearly $4 billion, went
GPS device manufacturers technically were responsible for building devices that
rejected interference from adjacent frequencies, but they were not expecting to
deal with powerful ground-based transmissions. Setting harm-claim thresholds
could anticipate the development of another LightSquared situation.
Pierre de Vries of the University of Colorado’s Silicon Flatirons Center in
Boulder is the principal author of the white paper. de Vries testified before
Congress last November on the issue of receiver standards. He said they should
be a “last resort,” and proposed the alternative of establishing harm-claim
thresholds that defined the “interfering signal levels that must be exceeded
before a service can bring a harmful interference claim.”
Comments are due June 21, 2013 on Docket No. 13-101; replies are due July 8.
~ Deborah D. McAdams
February 7, 2013,
Efficient Spectrum Use Calls for Receiver Standards
The majority of
TV stations operating today could be accommodated in a spectrum band ending at
Ch. 37—if receivers were
subject to performance standards.
November 29, 2012, “Lawmakers
Look Into Receiver Performance”
are viable alternatives to federal receiver performance standards, witnesses
told lawmakers at a hearing today.