NDGPS loses interior, keeps coast

July 25, 2016  - By and
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Heartland Corrections Services Now Commercial or WAAS-only

Original NDGPS coverage.

Original NDGPS coverage.

The U.S. Coast Guard, Department of Transportation and Army Corps of Engineers have reduced the number of Nationwide Differential Global Positioning System (NDGPS) sites that will be decommissioned. The course correction keeps a coastal and Mississippi River network of stations largely intact, while discontinuing inland services.

Last year at this time, the agencies sought public comment on a proposed shutdown of 62 of 84 NDGPS sites.

“After a review of the comments received, we have reduced to 37 the number of NDGPS sites to be shut down, nine of which are USCG Maritime sites and 28 of which are DOT inland sites,” the notice reads. “The NDGPS system will remain operational with a total of 46 USCG and USACE sites available to users in the maritime and coastal regions.”

Graphic depicting NDGPS coverage after site reductions. (U.S. Coast Guard)

Graphic depicting NDGPS coverage after site reductions. (U.S. Coast Guard)

Public use of NDGPS, never robust, has declined in large part due to limited availability of DGPS receivers. Many users and applications, particularly in precision agriculture, have shifted to commercially provided services or Wide Area Augmentation System (WAAS) corrections instead.
NDGPS coverage is maintained in major maritime ports and waterways. See www.federalregister.gov for a list of sites to be decommissioned. Termination of the broadcast signal is scheduled to occur by Aug. 5.


OCX Deep Dive Finds Progress, Need for Funds

The Pentagon seeks $39.2 million from Congress to speed the next-generation GPS ground control system (OCX) towards completion. Without the infusion, OCX would be delayed an additional four months and cost $90 million more to complete, the Pentagon said.

The embattled OCX showed progress in its July 7 quarterly review, according to an Air Force statement. DOD officials and Lt. Gen. Samuel Greaves, Space and Missile Systems Center commander, concluded Raytheon has made progress implementing critical changes.

On June 30, OCX exceeded baseline cost estimates by at least 25 percent, triggering a Nunn-McCurdy breach and potentially halting all work. Further OCX review will wind up in October. The Pentagon announced in 2015 that it was delaying initial OCX operations for the ground system until July 2021.

GPS III satellites. which may first launch in 2017, cannot use their full capabilities with the current ground control system, but the Air Force plans to use a retrofit to work with the GPS III designs until OCX is operational. See gpsworld.com/updatesyndrome for more details.


Galileo and the Brexit Effect

Tension Grows over the Public Regulated Service

By Tim Reynolds, European editor

UK involvement in the European Space Agency (ESA) should be unaffected by Brexit  — the UK leavetaking, as yet undetermined in its details, from the European Union. ESA is a separate institution from the EU. However, one could argue that non-EU-membership might diminish the UK voice and could require a higher financial contribution.

Bids for the next Galileo satellite purchase contracts were due in mid-July, and the European Commission indicated that it will consider them purely on commercial terms. Airbus Defence and Space and Thales Alenia Space were expected to bid, as was the incumbent supplier of the first 22 satellites, OHB SE of Bremen, Germany, with Surrey Satellite Technology Ltd. (SSTL) of Britain as OHB’s satellite payload developer.

The EU has historically been averse to non-EU companies taking major roles in Galileo, and the immediate question is whether the EC could accept an SSTL-built payload that would not be launched until after Britain’s exit is complete.

Paul Verhoef, ESA’s director of navigation, said he will manage the competition as if Brexit had not occurred, with no discrimination against British bidders. Marco R. Fuchs, chief executive of OHB, said OHB would continue the front-line role for SSTL.

Britain could negotiate a security similar treaty similar to one reached by Norway and the EU, that could become effective on the date of Britain’s departure.

If I were a betting man, I’d still wager the house on the incumbent consortium winning the contract to provide the remaining satellites required to provide a sustainable, 24/7 operational constellation for first-generation Galileo. There would, in my opinion, be an unwarranted technical risk in doing anything else.

However, for the next generation it is open season, of course.

PRS at Risk. The real worry must be for the Public Regulated Service (PRS). This is the unique feature of Galileo that is of great interest to civil and military authorities in Europe and beyond, due to its more robust encrypted signal and its potential anti-jamming and spoofing characteristics. Currently, PRS will only be available to EU Member States. However, other countries, including the U.S. and Norway, have indicated that they would love to be able to use it as well. No final decision on this has yet been made.

The loss of the automatic right to access PRS would be damaging to the UK, and potentially to the full Galileo deployment timetable, as the country is currently host to the back-up Galileo Security Monitoring Centre (GSMC) — an essential part of PRS infrastructure — and I cannot see any part of the PRS infrastructure being left in a non-member state. If the centre must be relocated, then deployment of the full service could be delayed.

In addition, UK involvement in research and innovation activities around PRS may be curtailed, even if other work on Galileo projects is not.

UK a PRS Leader. The UK has been a leader in developing PRS applications. Nottingham Scientific Limited (NSL) recently demonstrated cloud-based PRS applications including implementation of PRS authentication for an offender tag, done using live Galileo (and GPS) signals. The demonstration provided real-time authentication flag generation, release and delivery to users. A second demo used cloud-based PRS in a proof-of-concept remote, unattended timing station where the primary user requirement was 100-percent confidence for the validity of signal. A third demonstration illustrated the use of cloud-based PRS on a drone.

Dual-Use Debate

PRS was also a major talking point at the European Space Solution event in The Hague in May. A panel on Space and Security noted that despite the fact that Galileo is marketed as a civil controlled GNSS, “dual use” is becoming a potentially divisive area for debate.

Rini Goos from the European Defence Agency (EDA) said that the EU needed space systems to be able to “intervene successfully,” and that space strategy needed to support Member State defence capabilities. This meant that the next generation of EU space systems must have dual-use capability. NATO is entrusted with external defence of the EU, but the commission also needs to be able to provide defence, not just consume it, he concluded.

The current chairman of the Galileo Security Accreditation Board is a UK citizen, Jeremy Blyth. He said: “Space and security, security and space. Whichever way we say it, what is clear is that the two are inextricably linked together.” He believes that to ensure security, it must be “designed in from the beginning.” Security is an enabler, rather than a barrier, he claimed.

He also believes that PRS gives the EU a real and competitive edge in secure positioning.

However, he indicated that there is a need to think deeply and have a rational debate about dual-use systems and, in particular, about the interface between civil and military use.

Clearly, there is a growing tension with regard to overtly military use of Galileo both now and in future generations of the system. Although a largely philosophical debate, given who in reality will be controlling and using PRS within many Member States, many European and national policy makers will want to retain the “purity” of Galileo as a global positioning system under fully civilian control.

PRS Workshop

Security was also a key feature of the PRS workshop organised by the Netherlands EU Presidency toward the end of European Space Solutions. Ger Nieuwpoort, director of the Netherlands Space Office (NSO), reminded the audience that “For civil authorities, PRS provides the same level of security for Member States as the military in GPS.”

Bart Banning of the Netherlands Institute of Navigation asked “How will we use PRS?’” In terms of its use for protecting critical infrastructure, what if the owner of the infrastructure was a private company? Should it be granted access to PRS or have to make do with the Galileo Commercial Service, a.k.a. PRS-lite?

He also pointed out that PRS was no more protected against jamming than any other GNSS. And, currently, it was “not good for in-building, underground or underwater.”

He thought PRS could be a great time provider, but probably also needs ground transmission, possibly via legacy radio towers. However, he saw the “killer app” for PRS being asset tracking, such as for diamonds, VIPs or prisoners. He also agreed that for many EU countries, the ministry of defence will be overseeing PRS services. “PRS is a good and unique addition to GNSS — but not the answer to all our needs.”

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About the Author:


Alan Cameron is editor-at-large of GPS World magazine, where he has worked since 2000.

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