LightSquared Outlines Plan to Avoid GPS Interference

press release
Friday, October 21, 2011

Marine electronics industry still has major concerns.


An official of LightSquared, the company that has been under fire for its plan to offer mobile satellite services that could seriously interfere with Global Positioning System (GPS) signals, told a gathering at the 2011 NMEA International Marine Electronics Conference & Expo that solutions were in the works to prevent disruptions from occurring.

 

“Our integrated network will bring great benefits to wireless users nationwide, but at the same time we’re committed to ensuring this service doesn’t interfere with any GPS devices. We’re eager to work through any issues,” said Geoffrey Stearn, LightSquared’s vice president of spectrum development. He made his remarks at a meeting of the Global Maritime Distress and Safety System Task Force on September 28 in Fort Myers, Florida. The meeting was part of the National Marine Electronics Association’s (NMEA) annual four-day conference and expo.

 

Stearn accepted NMEA’s invitation to appear at the meeting to discuss the company’s plan to offer mobile satellite services from a frequency band next to that set aside for GPS. FCC-ordered tests conducted in April confirmed concerns that the high-powered LightSquared transmissions would significantly compromise GPS signals. Although the LightSquared frequencies don’t overlap with those allocated for the Global Navigation Satellite System (GNSS), which includes GPS, they are immediately adjacent. In radio transmissions such as these, there are always emissions that stray out of the allocated band and intrude on neighboring frequencies. The fear is that LightSquared’s transmissions would drown out GNSS signals because they are far more powerful.

 

Stearn told the task force, ”It was a surprise to us that there would be a [GPS] receiver overload.” He added that, based on data the company has collected, “We’re offering mitigation steps that we believe will solve the issue and will ensure our operation will be compatible with people’s continued use of GPS.” LightSquared has proposed the use of filters in GPS receivers along with power levels that the company says won’t interfere with GPS. It also agreed not to operate in a 23MHz band immediately adjacent to the GPS band, at least for now. “We still have licensed rights to the upper band channel,” Stearn said. “We’re not giving it up, but gave control to the FCC. We won’t operate there until the FCC says it’s okay.”

 

Several people who attended the LightSquared session expressed concerns later that the 23MHz guard band is temporary and that the company will eventually want to use the entire band, maybe at full strength. In addition, although GPS manufacturer Javad GNSS has developed a filter design that may take care of the problem, electronics experts said the design needed to be thoroughly tested by the industry. Bethel Marine Electronics owner Jules Rutstein expressed several concerns. “First of all is the contribution to the noise floor by these transmitters and their effect on GPS and other low-power reception devices. And, secondly, because of the type of transmission and the method used by GPS receivers, the problem will manifest itself as an intermittent problem.

 

“I believe that what we will see as a complaint from our customers will be a lost signal, and we will not be able to determine why the customer’s chart plotter occasionally will lose its fix. Intermittent problems by nature are more insidious, and since we will not be able to determine the source, it will be that much more difficult. Since the source of the problem may or may not be a function of its location, it may be just the wrong time.

 

“LightSquared has offered two solutions—one being filters and the other adding a 23Mhz isolation band to the frequency spectrum utilized. The filter is unlikely to be a good fix since it must be installed at the receiver, which may affect performance and on most installations will be impossible to implement. The other solution is the 23Mhz protection band. This will help somewhat, but fieldtesting will have to be done to validate effectiveness. They also mentioned power changes but did not answer the question as to how much and where. I personally feel that this project is being fast-tracked through the system and needs time for its impact to be evaluated.”

 

“This is an extremely important issue for our members as well as for anyone who relies on GPS, which is just about everyone,” said Bruce Angus, NMEA interim executive director. “We thank Geoff Stearn for coming to the conference and expo to discuss the problem and LightSquared for its commitment to avoiding disruption of the GPS system. We’ll be watching the resolution of this potential problem very closely.”

Maritime Reporter July 2015 Digital Edition
FREE Maritime Reporter Subscription
Latest Maritime News    rss feeds

People & Company News

U.S. Drillers Add Rigs Despite Crude Collapse

U.S. energy firms added 5 oil rigs this week after putting 21 rigs into service last week, the most in over a year, despite a collapse in U.S. crude prices from recent highs in June,

West Africa's August Crude Exports to Asia to Slip

West African crude oil exports to Asia were expected to fall to 1.84 million barrels per day (bpd) in August, Reuters data and a survey of traders showed.     Slower

DryShips Reaches Agreement with Ocean Rig

DryShips Inc. (NASDAQ: DRYS), a global provider of marine transportation services for drybulk and petroleum cargoes, and through its subsidiary, Ocean Rig UDW Inc.

Technology

NOIA Applauds Senate Passage of OPENS Act

NOIA President Randall Luthi issued the following statement on the Senate Energy and Natural Resources Committee’s passage of the OPENS Act, which will open new

Google Maps Goes Coastal with Unmanned Boat

A new high-tech unmanned vessel, launched with the help of Google, will use innovative technologies from the boatbuilding and mapping fields to map shorelines and

Bollinger Delivers 14th FRC to USCG

Bollinger Shipyards has delivered the 14th Fast Response Cutter (FRC), Heriberto Hernandez, to the United States Coast Guard (USCG). The 154-foot patrol craft

Marine Electronics

Google Maps Goes Coastal with Unmanned Boat

A new high-tech unmanned vessel, launched with the help of Google, will use innovative technologies from the boatbuilding and mapping fields to map shorelines and

Intelsat Records $598 mln Q2 Revenue

Satellite services provider Intelsat S.A. has reported total revenue of $598.1 million and net income attributable to Intelsat S.A. of $60.2 million, or $0.47 per common share on a diluted basis,

INTERSCHALT VDR Earns CCS Certification

INTERSCHALT maritime systems AG, the provider of maritime software, services and systems for navigation and communications systems (NavCom) and manufacturer of Voyage Data Recorder (VDR) systems,

Maritime Security

South China Sea Hotline in the Works

China and Southeast Asian nations have agreed to set up a foreign ministers' hotline to tackle emergencies in the disputed South China Sea, a senior official of

Three Rescued on Lake Tahoe

The Coast Guard and multiple agencies rescued three people Wednesday evening after they were reported missing on Lake Tahoe. At 9:45 p.m., Coast Guard Sector

Fond Farewell to HMAS Tobruk

The Governor-General, His Excellency General the Honourable Sir Peter Cosgrove, AK, MC (Retd), together with the Assistant Minister for Defence Stuart Robert, MP,

Marine Equipment

Thordon Bearings Secures AK Ferry Contract

Thordon Bearings has received an order to supply its COMPAC system to two Alaska Ferry newbuilds under construction at the Vigor Industrial shipyard in Ketchikan, Alaska.

UK Navy Chooses Effer Crane Again

Cranes manufacturer Effer informs its marine crane has recently been installed aboard the U.K. Royal Navy’s patrol vessel HMS Mersey.   The new 5s 275M crane,

Activists Block Shell's Arctic Drilling Quest

Greenpeace protestors dangling from a bridge on Thursday in Portland, Oregon, halted an icebreaker that Royal Dutch Shell needs in northern Alaska before it can

Maritime Safety

South China Sea Hotline in the Works

China and Southeast Asian nations have agreed to set up a foreign ministers' hotline to tackle emergencies in the disputed South China Sea, a senior official of

Three Rescued on Lake Tahoe

The Coast Guard and multiple agencies rescued three people Wednesday evening after they were reported missing on Lake Tahoe. At 9:45 p.m., Coast Guard Sector

AEU Presents Safety Awards

The American Equity Underwriters, Inc. (AEU) presented its 2014 Safety Awards at the annual American Longshore Mutual Association, Ltd. (ALMA) Conference on July 19, 2015, in Key Biscayne, Fla.

 
 
Maritime Careers / Shipboard Positions Maritime Security Maritime Standards Naval Architecture Navigation Pod Propulsion Ship Electronics Shipbuilding / Vessel Construction Sonar Winch
rss | archive | history | articles | privacy | contributors | top maritime news | about us | copyright | maritime magazines
maritime security news | shipbuilding news | maritime industry | shipping news | maritime reporting | workboats news | ship design | maritime business

Time taken: 0.1963 sec (5 req/sec)