February 21, 2017
This is a re-post from NPSTC.org – Note that quite a way down in the post it reads “The report presents a huge amount of data, including numerous plots of test results, but it does not reach conclusions about whether LTE signals would cause harmful interference to GPS devices.”
February 17, 2017 – Ligado Networks LLC said that a 428-page report released this week by the National Advanced Spectrum and Communications Test Network (NASCTN) on the impacts of LTE signals on GPS receivers validates that the LTE network Ligado wants to deploy can operate without harming the performance of GPS devices. Company representatives said the report completes the record in the FCC’s Ligado proceeding, and they said the agency should move ahead to act on its authorization request.
“Ligado’s very pleased that NASCTN has issued its report on the compatibility of GPS devices with LTE deployed in adjacent bands. We’re looking forward to reviewing fully this comprehensive and extensive collection of data, but our initial review indicates that this data supports the conclusion reached by the major GPS companies over the last 14 months: And that conclusion is that a Ligado network built to the specifications proposed in the pending FCC application can operate alongside GPS devices without harming the performance of GPS,” Valerie Green, Ligado’s executive vice president and chief legal officer, told reporters during a conference call.
“The NASCTN report is really the last piece of information that the regulatory decision-makers like the FCC need to move forward with Ligado’s pending application. This government report is objective, and it is impartial,” she said.
“This report completes the technical evaluation of how Ligado proposes to use its spectrum for ground-based services, and is the last in a long line of testing by multiple stakeholders,” Doug Smith, the company’s president and chief executive officer, said in a statement. “The regulatory decision-makers now have the information they need to make this 35 MHz of vital mid-band spectrum available to serve critical American infrastructure needs and deliver substantial economic benefits to our nation.”
The NASCTN testing was conducted under a Cooperative Research and Development Agreement. NASCTN was established in 2015 by the National Institute of Standards and Technology, the National Telecommunications and Information Administration, and the Department of Defense to look for ways to increase access to spectrum for commercial and federal government entities (TRDaily, March 25, 2015).
“NASCTN testing included several measurands: carrier-to-noise density (C/N0), 3D position error, timing error, number of GPS satellites in view, time to first fix and time to first reacquisition,” a summary of the project noted. “The NASCTN test plan focused on GPS devices from four different receiver classes – general location and navigation (GLN), high-performance positioning (HPP), real-time kinematic (RTK), and GPS-disciplined oscillator (GPSDO).”
“Over a three-month period, NASCTN performed the radiated measurements associated with this project at two facilities – a semi-anechoic chamber at National Technical Systems (NTS) in Longmont, CO and at a fully-anechoic chamber at the NIST Broadband Interoperability Testbed (NBIT) facility in Boulder, CO,” the summary noted. “NASCTN relied on technical staff from NIST and the U.S. Army’s Electronic Proving Grounds to perform and validate the measurements and collect the data.”
“In total, NASCTN performed 1,476 hours of testing and collected over 19,000 data files for a variety of measurands that were collected from a number of GPS devices,” the summary said. “These data were collected at a baseline condition (no LTE signals present) and over a large range of LTE signal power levels. Subsequent data processing yielded a set of 3,859 anonymized data files (780 MB) that is available along with the NASCTN report.”
The report presents a huge amount of data, including numerous plots of test results, but it does not reach conclusions about whether LTE signals would cause harmful interference to GPS devices.
January 20, 2017
Editor’s Note: Each satellite has four clocks aboard, so these failures have not been fatal for the system, nor even an individual satellite. They are worrying, though, as you will read below.
Galileo satellites experiencing multiple clock failures
The onboard atomic clocks that drive the satellite-navigation signals on Europe’s Galileo network have been failing at an alarming rate.
Across the 18 satellites now in orbit, nine clocks have stopped operating.
Three are traditional rubidium devices; six are the more precise hydrogen maser instruments that were designed to give Galileo superior performance to the American GPS network.
Galileo was declared up and running in December.
However, it is still short of the number of satellites considered to represent a fully functioning constellation, and a decision must now be made about whether to suspend the launch of further spacecraft while the issue is investigated.
Prof Jan Woerner, the director general of the European Space Agency (Esa), told a meeting with reporters: “Everybody is raising this question: should we postpone the next launch until we find the root cause, or should we launch?
“You can give both answers at the same time. You can say we wait until we find the solution but that means if more clocks fail we will reduce the capability of Galileo. But if we launch we will at least maintain if not increase the [capability], but we may then take the risk that a systematic problem is not considered. We are right now in this discussion about what to do.”
Each Galileo satellite carries two rubidium and two hydrogen maser clocks. The multiple installation enables a satellite to keep working after an initial failure.
All 18 spacecraft currently in space continue to operate, but one of them is now down to just two clocks.
January 10, 2017
Editor’s note: A good reminder that the federal government still has all the properties needed for a quick implementation of system to defend GPS. And who would have thought that folks in Las Vegas, NV would be so aware of the issue?
First wave: Is a comeback in store for Searchlight’s radio positioning station?
Sunday, Jan. 8, 2017 | 2 a.m.
At the end of an unmarked, barely passable road a few miles south of Searchlight sits a shuttered government installation. To some, it is a silent monument to a technology whose time came and went. To others, it’s symbolic of a colossally penny-wise but pound-foolish decision that put the nation’s security at risk.
The site is a former LORAN-C station — LORAN, for LOng RAnge Navigation. For more than 30 years, it broadcast a powerful, low-frequency radio beacon to help ships and planes fix their positions and find their way home.
In February of 2010, however, the Searchlight LORAN station fell silent, along with roughly two dozen similar stations throughout the country. The Obama administration figured the World War II-era technology was obsolete in an age of global-positioning satellites, and that the annual $40 million budget could be better spent.
“This system once made a lot of sense, before there were satellites to help us navigate,” Obama said in a May 2009 speech. “Now there’s GPS. And yet, year after year, this obsolete technology has continued to be funded even though it serves no governmental function and very few people are left who still actually use it.”
But the nation’s GPS system has proved vulnerable to hacking, jamming and interference from solar flares. LORAN, at least an upgraded version, is being presented as a safety net for GPS. And those behind the effort see the decision to shut down America’s LORAN sites as dangerous.
At the end of an unmarked, barely passable road a few miles south of Searchlight sits a shuttered government installation. The site is a former LORAN-C station — LORAN, for LOng RAnge Navigation. For more than 30 years, it broadcast a powerful, low-frequency radio beacon to help ships and planes fix their positions and find their way home.
“It was absolutely a mistake,” says Dana Goward, a retired Coast Guard captain. “It was a case of people at several levels of government not paying attention to the engineers and senior leaders, including four-star admirals; deliberately ignoring them to claim they had saved the government money when, in fact, they were endangering the nation.”
January 4, 2017
Editor’s Note: This looks like an interesting event at the New York Stock Exchange. We are going to attend. A similar event was hosted there last year that included a demonstration using an eLoran signal for a timing reference. DG
Time and Money Workshop
Join us for the Time and Money Workshop on January 25 at the New York Stock Exchange, where finance and trading software specialists and telecom experts–the professionals managing time for the entire network– will discuss leading issues in time transfer and what it takes to deliver accurate time for financial transactions.
Visit the Time and Money Workshop website for the full agenda.
Space is limited, Register today!
January 1, 2017
Editor’s Note: For years the US administration has turned a blind eye to problems of jamming and spoofing of all kinds. The example below of millions of dollars wasted in foreign aid trying to counter Russia in the Ukraine is a relatively benign example compared to the potential problems that could be caused within the US.
Exclusive: U.S.-supplied drones disappoint Ukraine at the front lines
Millions of dollars’ worth of U.S.-supplied drones that Kiev had hoped would help in its war against Russian-backed separatists have proven ineffective against jamming and hacking, Ukrainian officials say.
The 72 Raven RQ-11B Analog mini-drones were so disappointing following their arrival this summer that Natan Chazin, an advisor to Ukraine’s military with deep knowledge of the country’s drone program, said if it were up to him, he would return them.
“From the beginning, it was the wrong decision to use these drones in our (conflict),” Chazin, an advisor to the chief of the general staff of Ukraine’s armed forces, told Reuters.
The hand-launched Ravens were one of the recent highlights of U.S. security assistance to Ukraine, aiming to give Kiev’s military portable, light-weight, unarmed surveillance drones that were small enough to be used widely in the field. They are made by AeroVironment.
But they appear to have fallen short in a battle against the separatists, who benefit from far more sophisticated military technology than insurgencies the West has contended with in Afghanistan, Iraq or Syria.
December 30, 2016
The Air Force announced the assignment of Brig. Gen. Kevin Kelly to be Deputy DOD Chief Information Officer for Command, Communications and Computers (C4) and Information Infrastructure Capabilities. The post is a critical player in DOD positioning, navigation and timing (PNT) policy and decisions. The incumbent has also served as a part of the inter-department senior leadership team supporting the PNT Executive Committee led by the Deputy Secretaries of Defense and Transportation.
The incumbent is Maj. Gen. Sandra Finan who has been in the job since January 2016. Before her Maj. Gen. Robert Wheeler served in the position.
December 20, 2016
Last month the US Security and Exchange Commission (SEC) voted to accept as a part of the National Market System a Consolidated Audit Trail data base. This included a provision that:
“Tightened the clock synchronization standards for SROs to within 100 microseconds of the time maintained by the National Institute of Standards and Technology to enable regulators to better sequence order events across multiple exchanges and required the SROs to assess industry standards for clock synchronization based on the type of market participant or system, rather than the industry as a whole…”
The move in the US follows a similar action in Europe implementing MIFD II standards.
SEC Press Release
December 2, 2016
Blog Editor’s Note: Another excellent article below by Dee Ann Divis. One additional note – the federal register notice focuses on timing, which has always been the first phase of the effort for a complimentary and backup system for GPS. It also says that the government is interested in technologies’ “… capability to extend service(s) in the future to provide positioning/navigation continuity as well.” DG
Dee Ann Divis
December 1, 2016
Federal officials are finally moving on a year-old, two-phase plan to establish a long delayed backup for the GPS system.
The Department of Transportation (DoT) posted a request for information (RFI) in yesterday’s (November 30, 2016) Federal Register seeking input from companies interested in providing a second source for the type of timing data now provided by GPS. That ubiquitous, extremely accurate data is essential to the smooth operation of the vast majority the country’s critical infrastructure, including its cell phone networks, power grids, Internet pipelines, and banking systems.
“RFIs are frequently one of the first steps when the government wants to obtain either goods or services,” said Dana Goward, the president of the Resilient Navigation and Timing Foundation, which has been advocating for a GPS backup system. “It seems to me, in this instance, the government is leaning towards obtaining services because they talk about being interested in proposals for service level (cooperative) agreements and public-private partnerships, which we think is a good thing.”
Indeed, the government said it would be open to suggestions on ways to access such services and handle cost sharing — as well as asking for industry’s view of the market for a timing service. It also seems open to making changes to clear a way for new approaches.
October 28, 2016
In a letter to each of the members of the Senate Committee on Commerce, Science and Transportation the Council of American Masters Mariners urged appointment of a single agency to be responsible for implementing an eLoran system and measures that would empower that agency to quickly implement it.
The letter cited GPS disruptions ashore and at sea that have caused problems for maritime commerce, as well as the Commandant of the Coast Guard and other high ranking officials calling GPS “a single point of failure for critical infrastructure.”
In an enclosure to the letter the organization cited numerous ways that an eLoran system might be established at little or no cost to the government.
And they stressed the importance of addressing the issue now, before curren session of Congress ends.
Read entire letter
October 21, 2016
Editor’s Note: Don Jewell was a member of RNT Foundation’s first Advisory Council. As a practical navigator, scientist and student of public policy, he was an articulate and insightful observer whose contributions were of great value to any discussion of PNT. He will be greatly missed.
With great sadness we report that Don Jewell passed away unexpectedly on October 12. For more than nine years Don wrote the Defense PNT monthly e-newsletter column for GPS World, after a distinguished career in the U.S. Air Force, retiring as Deputy Chief Scientist for Air Force Space Command with the rank of Lieutenant Colonel. A service of remembrance and celebration of his life was held on October 20 in Colorado Springs, Colorado.