[time-nuts] LightSquared gets at least some political attention
magnus at rubidium.dyndns.org
Fri Apr 15 17:51:27 UTC 2011
On 04/15/2011 07:00 PM, Pete Lancashire wrote:
For the first time in ages a broken page. Extracted text for those who
experience the same:
LightSquared GPS Interference Issue Flares Again in Senators' Letter
Posted In: Government | GPS | FirstNews
By Maisie Ramsay Friday, April 15, 2011
Senators Pat Roberts (R-Kan.) and Ben Nelson (D-Neb.) want the FCC to
stop LightSquared from deploying its LTE network until it proves its
service doesn't interfere with GPS services.
In an open letter released yesterday, the lawmakers asked their fellow
senators to call on the FCC to ensure that GPS service is not
compromised in any way by LightSquared's planned hybrid-satellite LTE
LightSquared plans to deploy its services on spectrum directly adjacent
to GPS bands. The company has developed filters to stop its signal from
bleeding into GPS service, but major GPS stakeholders, including the
Defense Department, fear that widespread GPS "dead zones" are inevitable
if LightSquared's network goes live.
"The full Commission must be involved and require LightSquared to
objectively demonstrate non-interference as a condition prior to any
operation of its proposed service," the Senators wrote in their letter.
"Anything less is an unacceptable risk to public safety."
GPS systems are used by the military, public safety, aviation and
consumers. The technology is also used in critical applications across a
wide swath of U.S. industries, including agriculture and civil engineering.
LightSquared received a waiver from the FCC earlier this year to use
spectrum formerly reserved for satellite services for land-based LTE
services. The L-Band spectrum is located next to bandwidth used by
highly sensitive GPS receivers, which also use parts of the L-Band
spectrum to fine-tune their coordinates.
Many in the GPS industry say the signal sent out by LightSquared's
network of 40,000 base stations will create major interference problems
that will overwhelm GPS receivers.
"LightSquared is trying to define the potential for interference in a
very narrow way – if they filter it so none of the signals go out of
their band, that's all they have to do," says Jim Kirkland, general
counsel at Trimble. "They say we're eavesdropping on their band, but I
would say we can't help but hearing what they're doing in their band."
The FCC has said it will not allow LightSquared to launch commercial
services until the GPS interference issue is addressed, but that has
done little to assuage fears of the GPS industry.
SkyTerra, which later became part of LightSquared, first proposed
incorporating a land-based component into its L-Band satellite services
in 2003. The company also worked with the U.S. GPS Industry Council
(USGIC) at the time to manage interference posed by out of band emissions.
Manufacturers of GPS equipment continued building receivers that
listened in to portions of the L-Band after 2003, a practice Kirkland
says is for legitimate technical and business reasons.
Jeff Carlisle, head of government and regulatory affairs at
LightSquared, says GPS receivers should have been designed differently
after 2003. The FCC does not regulate receivers, only transmitters,
adding to the complexity of the issue.
"Even though our transmitter is doing exactly what it's supposed to do
and not sending any signal into GPS, the receiver is looking into our
spectrum either by accident or design," Carlisle said in an interview
conducted earlier this month. "There's no problem with that until the
receiver crosses the boundary into our area. After 2003, the receivers
should have been designed so they were protecting themselves from that
LightSquared says it spent $9 million to develop filters to minimize
interference issues and has formed an FCC-mandated technical working
group with the U.S. GPS Industry Council (USGIC) to study the issue.
LightSquared is set to file a new report from the technical working
Carlisle said in a statement that LightSquared is confident the
interference issues can be addressed, and reiterated the company's
intention to launch commercial operations only after the FCC is
satisfied with the review process.
"To ensure that the LightSquared network and the GPS systems can
coexist, we will continue to work collaboratively with federal agencies
and the GPS community, just as we have over the past ten years since the
proposed scope of LightSquared's terrestrial network was first publicly
announced," Carlisle said.
LightSquared has already signed up Best Buy and Cricket Communications
for its wholesale LTE service and plans to begin commercial operations
in the first quarter of next year. It is not clear whether the issues
with potential GPS interference could affect the company's launch plans.
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