I have a seven-year-old drawing of GPS satellites in their orbital planes that I found (can’t recall where) some years ago, either on a website or from a colleague who attended some GPS forum. Would you know of a site where I can find current information on GPS satellite locations, which ones have been decommissioned, and which ones have been replaced?
— Grace Pazos
Richard Langley replies:
I don’t know of a plot that shows the locations of all decommissioned and/or replaced satellites (some of them would have been boosted out of the GPS orbit planes), but relatively current information on the active and backup satellites can be found here, and a plot here (and depicted below). I update the table and plot roughly every six months. Earlier versions are available on request.
Constellation snapshot for a specific date/time: GPS week 1749 (725) and GPS seconds 86400 = July 15, 2013, at midnight GPS Time.
Survey Scene Newsletter Mail
Thanks for the insightful update on the ESRI User Conference and the Survey Summit. For those of us who can’t afford to travel, it helps to get the scoop on these events. It is interesting to me that the push towards the future includes heavy emphasis on lighter and simpler small platform apps, cloud-based GIS, and 3D visualizations, and less emphasis on the building blocks of geodesy, cadastral data, and surveying. It almost seems like the GIS community is pushing the hard stuff under the rug and focusing on what is new and shiny. And doing this while talking about higher quality standards.
Keep up the good work, thank you.
— David Scherf, Manager of GIS/Technical Services, Torrington, Connecticut
Eric Gakstatter replies:
Thanks for the comments. If you’ve followed my series “Nightmare on GIS Street,” you’ll see that I’m trying to raise awareness of the importance of geodesy in GIS. I don’t believe that most people are sweeping this subject under the rug because it’s a difficult subject, but just that they aren’t aware that it’s a problem. Secondly, if they do recognize the problem, many don’t know how to solve it. There’s definitely a knowledge gap, and an opportunity for geodesists (or qualified surveyors) to contribute.
Defense PNT Newsletter Mail
Thank you for your tribute to Col. Duke Kane’s many contributions beyond the GPS community. I was also sad to hear of his passing. I met Duke in the late 1980s and watched with considerable interest as he established the GPS International Association.
He felt strongly that the GPS users needed their own forum to voice user interests similar to that which had recently been established for GPS industry via the U.S. GPS Industry Council. His foresight and energy will be missed.
— Jules McNeff, Overlook Systems Technologies, Inc., Vienna, Virginia
Don Jewell replies:
Thanks for your kind words. Of course you and I knew Duke well, and you are correct, he made many significant contributions beyond GPS, even though it was a major accomplishment in which he was always very proud to have had a role to play.
Duke Kane was my uncle, and I can tell you the germinal event that grabbed his interest in flight. While a young boy, Duke and my father Jack (Duke’s older brother) pooled their resources and bought a very popular adolescent novel by Nordoff and Hall (these authors also wrote Mutiny on the Bounty) called Falcons of France, written about two young American boys who volunteered to fly for France in World War I before the United States entered the conflict. Duke’s eyes were set skyward ever after.
Aerospace GNSS receivers constitute a class apart, compared to their more popular relatives used in automotive, cell phone, or survey applications. Automotive and cell-phone receivers can sometimes provide position information even in indoor environments. The survey class of receivers provides centimeter-level accuracies. However, neither group can guarantee the reliability and integrity of the position solution, and users rely upon them at their own risk, and only in non-critical applications.
On the other hand, an aerospace GNSS receiver not only provides decimeter-level accuracy, but it also guarantees that the position error is bounded by an integrity limit. The probability that the position error is more than the integrity limit is very rare: one in ten million times.
Now, isn’t that the best class of GNSS receiver?
A certified aerospace GNSS receiver stands as the keystone of the Federal Aviation Administration’s (FAA’s) ambitious NextGen Aviation program for the United States. The FAA developed NextGen to revolutionize the way an aircraft flies in the U.S airspace. In its June 2013 update report, the FAA states that “NextGen is providing major benefits to the general aviation community. The Wide-Area Augmentation System (WAAS) has improved general aviation access to more than 1,500 airports in all kinds of weather with no costly investment in ground infrastructure.”
According to the report, by the end of the NextGen mid-term in 2020, NextGen improvements will reduce delays by 41 percent from today. The FAA estimates that by 2018, NextGen will reduce aviation fuel consumption by 1.4 billion gallons, reduce emissions by 14 million tons, and save $23 billion in costs. NextGen also has an important safety impact for air travelers.
Tens of thousands of aircraft are already equipped with WAAS receivers, which improve the availability, accuracy, and integrity of GPS signals. Pilots take advantage of WAAS technology to fly approach procedures using Localizer Performance with Vertical Guidance (LPV) to altitudes as low as 200 feet. The FAA has published 3,123 WAAS LPV approaches as of May 2013 and expects to publish 5,218 by 2016.
The key to NextGen is the aerospace GPS-SBAS receiver.
How different are aerospace GNSS receivers from commercially available receivers, including high-precision receivers?
An aerospace GPS-SBAS receiver is characterized by very high reliability, accuracy, and availability. Among these attributes, the reliability factor is the most important parameter. Misleading information from an aerospace receiver should be extremely improbable, since that can lead to hazardous or severe major consequences to the aircraft, its passengers, and flight crew.
Table 1 shows the major differences between a standard GNSS receiver and an aerospace GNSS receiver.
Table 1. Differences between a standard GNSS receiver and an aerospace GNSS receiver.
Performance Requirements
The DO-229D standard document — formally, the RTCA Minimum Operational Performance Standards for GPS/WAAS Airborne Equipment — specifies the minimum performance standards of an aerospace GPS-SBAS receiver. In particular, an aerospace GNSS receiver needs to meet the GPS and SBAS signal processing requirements, GPS and SBAS data/message processing requirements, satellite integrity status requirement, accuracy requirements in presence of interference, dynamic range and sensitivity requirements, and so on, as defined in DO-229D standard.
Most importantly, the receiver must meet the Receiver Autonomous Integrity Monitoring (RAIM) requirements for en-route, terminal, non-precision and precision phases of flight of DO-229D. Additionally, the receiver must meet the fault detection, fault exclusion, missed alert, false alert, step detection, ramp detection, and other integrity-related requirements of DO-229D.
Further, the receiver needs to meet the environmental conditions specified in DO-160 standard for temperature, temperature variation, altitude, humidity, shock, vibration, magnetic effects, voltage spike, EMI/EMC, lightning, and so on.
Safety and Reliability Aspects
A Functional Hazard Assessment (FHA) based on the intended function of the GPS-SBAS receiver software needs to be carried out to determine whether the receiver meets the requirements of hazardously misleading information. The safety and reliability aspects of the receiver are computed through Failure Mode and Effect Analysis (FMEA) and Fault Tree Analysis (FTA). The effects of each failure mode are determined at the system level for each operating mode of the equipment.
RAIM. For an aerospace GPS-SBAS receiver, RAIM is of paramount importance. The measure of protection provided by RAIM is given by Horizontal/Vertical Protection Limits (HPL/VPL). HPL is used as the protection limit for en-route, terminal, and LNAV (Non-precision approach) phases of flight and compared against the Horizontal Alert Limit (HAL) for the phase of flight. Whereas, VPL is compared against the Vertical Alert Limit (VAL) for the LNAV/VNAV and LP/LPV phase of flight.
The most critical part of the integrity requirement is to detect a satellite failure and, if possible, to make corrective actions in addition to generating timely alerts. A Failure Detection and Exclusion algorithm, often known as FD/FDE, is to be implemented in an aerospace GNSS receiver. The effectiveness of the FD/FDE algorithm has to be tested extensively in off-line condition for availability of satellite failure detection and exclusion. Further, the algorithm has to be tested in on-line conditions as well as on a target environment. There has to be a match among the off-line,
on-line, and on-target test results for using the algorithm in
the GNSS receiver.
The integrity tests on an aerospace GNSS receiver are carried out as per the guidelines in DO-229D. This requires simulation of the GPS orbit and determination of satellite visibility at more than two thousands grid points on the Earth surface and for 12 hours at 5-minute time intervals. The FD/FDE algorithm is validated at each space-time point to determine the availability of failure detection and exclusion.
For the non-precision approach, the space-time points are arranged in terms of the HPL values and Horizontal Exclusion Limit (HEL) values and the most difficult to detect/exclude satellite is identified. Extensive Monte Carlo simulations are carried out at the selected space-time points to validate the false alert and missed alert requirements of DO-229D standard. Similar tests are carried out on the GNSS receiver for the precision approach, wherein the VPL values are considered instead of HPL values. Further, the test results of the off-line tests are validated through comprehensive on-line and on-target tests on the selected space-time points.
Certification Aspects
To ensure that the software and the firmware of the aerospace GNSS receiver are robust, providing adequate levels of safety and reliability, the receiver software and firmware need to be developed conforming to the software and hardware design assurance standards — DO-178B and DO-254 respectively. Based on the criticality of the end application, the design assurance should meet DO-178B and DO-254 objectives of Level A, B, or C criticality.
An aerospace GNSS receiver needs to be certified by the FAA (or other competent authorities in other countries) for airworthiness. The FAA gets involved in the certification process right from the planning stage and oversees the compliance of the entire development process as per DO-178B and DO-254 standards. The aerospace GNSS receiver software and firmware undergo extensive verification and validation processes. Further, the GNSS receiver is subjected to all the functional and environmental tests as per DO-229D and DO-160 standards respectively under FAA supervision. Only after the successful completion of all the software, hardware, and systems tests, the receiver is certified by the FAA for airworthiness through Technical Standard Order TSO-C145 Authorization (TSOA).
Conclusion
Aerospace GNSS receivers, by virtue of their inherent safety, reliability, and integrity, are far more suitable for critical applications, where an error could have hazardous or catastrophic consequences. These receivers must be used in commercial transport aircraft, business jets, general aviation aircraft, gliders, experimental aircraft, balloon, and so on. Further, in airport surface vehicles and mass-transport vehicles such as high-speed trains, trams, and unmanned autonomous vehicles of all sorts, whether ground or air, receivers similar to aerospace GNSS receivers should be used for navigation and surveillance purposes.
Jaynata Ray received his Ph.D. from the University of Calgary. He has worked in the GPS field since 1992, and is group manager at Accord Software and Systems in Bangalore, India. He is a member of GPS World’s Editorial Advisory Board.
In recent years, the sporting world has seen an explosion in the use of GPS. You will rarely spot a runner or cyclist on the road without either a smartphone strapped to their arm or a dedicated GPS device clamped to their handlebars, tracking their every move.
The amount of information that the modern sportsperson — from casual amateur to full-time professional — logs, analyzes, and shares is phenomenal. There are now dozens of ways of uploading data for the whole world to share and study.
As more manufacturers come to this market with the hope of capturing a share of it, they face the challenge of effectively developing and then testing their devices. Among many factors to consider, new products must have capability for local constellations such as BeiDou, GLONASS, and QZSS, not just GPS alone. New market entrants won’t have the same budget as the established big players, and constantly traveling to China or Japan to try out a new gadget will escalate costs to an unsustainable degree.
Then there’s the issue of getting out into the kind of environment in which you imagine your new sporting GPS device will be put to use. In many cases this will be remote: forests, hills, and mountains. Stepping outside to the office car park does not constitute a sufficient test for satellite acquisition and retention. Neither does simply driving the commute route home with it.
A GPS simulator or replay device allows for bench testing, but such devices are expensive. They might not actually fulfill your testing requirements, either: a traditional GPS simulator outputs its scenarios based on constellation modeling, either as a perfect signal or one that has simulated multipath. But you need to genuinely know how your new product will operate through, say, a forest on a downhill mountain bike run, or during a city marathon through urban canyons, or on a trail under wet trees. Adventure sport participants want to record their achievements wherever they go.
How do you obtain this kind of realistic scenario? It will require the use of a GNSS recorder, and in an ideal world you would lend it to someone who actually does some of this stuff. Perhaps one of your colleagues is an (insane) downhill skier — who better to capture exactly that type of data, which you can replay back in a nice warm lab?
The trouble is that a person of this sporting ilk will be unwilling or unable to carry bulky equipment that weighs several kilos. It will slow them down, so a GNSS recorder that can be easily carried without affecting the sporting activity is essential. It has to be easy to use: self-contained, with a battery that will last a couple of hours, and with one big button to start and stop recording. The user shouldn’t need any training in its operation. And ideally, it won’t need a large ground-plane antenna to capture usable data; a well-designed unit will employ a sensitive GPS engine allowing for as complete a signal as possible to be logged through a standard passive antenna.
Looking further afield, other industries will soon be seeking a device with this level of convenience. For instance, agricultural and automotive manufacturers want the ability to send test engineers out to record drive-cycle tests easily and in a variety of vehicles. Additional features, such as controlled area network (CAN) and inertial sensor logging, synchronized with the GNSS data, will also find favor.
The nature of the simulation market is changing: increasing numbers of developers need not just a traditional constellation simulator, but rather a replay device that is feature-rich and that doesn’t cost the earth.
Economies of scale will likely dictate the way that this develops, and GNSS simulation will no longer be the specialist and exclusive field it once was.
Mark Sampson is the LabSat product manager for RaceLogic, based in Buckingham, UK.
An occasional reader of these pages forwarded a clipping from a summer Wall Street Journal, a book review of the new title, Curiosity: How Science Became Interested in Everything, by Philip Ball (University of Chicago Press, 465 pages, $35).
The book covers scientific advances logged in the 1600s, a century that “began with an essentially medieval outlook and ended looking like the first draft of the modern age.” However, the book’s description by WSJ reviewer Timothy Ferris quickly called to my mind the current status of investigation — practiced with an overlay of capitalism and market advantage-seeking — by, guess who, the GNSS community.
Not that I’m necessarily equating the scientists, engineers, and product managers who are responsible for most of the contents of this magazine with the “thousands of independent tinkerers, inventors, collectors and flat-out oddballs, the ‘virtuosos’ as they were called, [who] experimented with lenses, pumps, and biological specimens as much to satisfy their own inquisitiveness as to answer big questions.”
Far from it. Perish the thought.
And yet, and yet . . . .
I sat in a Denver airport cafe on my way home from ION GNSS+, chatting with a couple of industry captains about the way forward. We joked about how our kids will look at us as old fogeys — heck, they already do — tentatively feeling our way to indoor navigation. This method, that method? This augmentation, that integration?
The rising generations will simply take it for granted: indoor nav works everywhere, all the time, in the palm of your hand, or perhaps in the frame of your eyewear. How quaint were those early 21st-century inventors! Tinkering with different RF bands, trying to cobble together a solution.
The smiles on the faces of these industry captains as they proudly showed each other their devices, running their latest prototypes, and curiously examined their competitors’ versions, betrayed an enthusiasm, not just for market share, but for intellectual stimulation, the thrill of the chase, the joy of solving a problem. In that way, they were not unlike the 16th century crew, an assemblage that included, among many minor and forgotten names, Galileo (!!!), Kepler, Newton, Descartes, and Leibniz.
“The truth is that science works,” writes Philip Ball, “only because it can break its own rules, make mistakes, follow blind alleys, attempt too much — and because it draws upon the resources of the human mind, with its passions and foibles as well as its reason and invention.”
Russian scientists and engineers are at work on a new code-division multiple-access signal format to be broadcast on a new GLONASS L3 signal. Taking an approach similar to that implemented on the newly designed GPS L5 signal, this will, once implemented across the constellation by new satellite launches, facilitate interoperability with and even eventually interchangeability among other GNSS signals, including of course GPS.
An article in the November issue of GPS World, authored by Alexander Povalyaev, the deputy head of division in JSC Russian Space Systems and a professor at the Moscow Aviation Institute, will give an outline and provide some details on a new flexible navigation message format proposed for use in the GLONASS CDMA signal under development. The format allows for relatively easy upgrades in the navigation message, if required.
Navigation messages developed and broadcast so far, by both GPS and GLONASS, are fixed, regular structures including pages (frames), subframes (rows), and words. Despite their simplicity, “such structures are very conservative indeed,” says Professor Povalyaev. The only possibility to update such navigation messages is restricted to the use of previously allocated backup frames. Increasing numbers of such frames make for ineffective use of navigation message transmission capacity. Conversely, the relatively small number of backup frames restricts the potential for future navigation message upgrades.
Prof. Povalyaev states that a comparison of data transmission via GLONASS and GPS, respectively, reveals that the data transmission rate in GLONASS is 5 times greater than in GPS. This explained by the higher redundancy of the GPS navigation message. In addition to approximately 11 percent of its subframes in backup, the GPS signal reserves fields for transmission of 32 satellite almanacs. As a result, Povalyaev believes that the GPS navigation-message transmission channel used inefficiently.
For GLONASS, the situation is different, with fewer backup bits in the navigation message, and fields reserved for transmission of only 24 satellite almanacs. This increases transmission channel efficiency but creates problems when it comes to updating the system, particularly in maintaining backward compatibility for previously manufactured user equipment. From this point of view, he says, a large number if backup frames in preferable.
He proposes a GLONASS navigation message with flexible row structure, as was used for the first time in the design of the GPS L5 signal. In this structure, the navigation message is formed as a variable row flow of different types. Each row type has a unique structure and contains specified information type, for example, ephemeris, almanacs of specific satellites, parameters of Earth pole movement models, parameters of ionospheric delay models, and so on. He goes on to describe how signal-processing disruptions in legacy user equipment can be avoided.
A flexible row structure of the navigation provides more effective use of transmission channel capacity. The main advantage of the flexible row structure is the possibility of its evolutional upgrade, meeting the requirements of backward compatibility.
Currently GLONASS uses signals with frequency separation in L1 (1592.9 – 1610 MHz) and L2 (1237.8 – 1256.8 MHz). The foreseen upgrade, already underway with one recently launched GLONASS satellite transmitting an L3 signal, will permit, in the long term, signals with code separation in L1, L2, and L3 (1190.35 – 1212.23 MHz).
Look for further details in the November issue of GPS World magazine.
A watershed moment may be approaching for the connected vehicle market. The National Highway Traffic and Safety Administration (NHTSA) is about to start on the path towards mandating connected vehicle technology. Interest in the market is not limited to a few countries; last week I moderated a GPS World webinar on the connected vehicle that drew registrants from 40 countries. Other news in the industry includes Sprint removing Sprint Navigation and TeleNav GPS Navigator from bundled data and data add-on plans. A new report shows it has become more expensive to acquire app users. And despite no longer being preinstalled on iOS devices, Google Maps is doing pretty well with Apple iOS users.
During our GPS World connected vehicle webinar, held September 19, I noticed differences in how the audience characterized the connected vehicle. The connected vehicle enables information to be exchanged with other vehicles, devices and/or road infrastructure to provide safety, mobility and consumer functionality. The devices that are used with the connected vehicle can be nomadic (phone, tablet, personal navigation devices), vehicle embedded and aftermarket devices. Communication options are currently cellular, Wi-Fi or DSRC/WAVE.
Regulation Pushing Connected Vehicle Forward. In a recent statement, the National Highway Traffic and Safety Administration (NHTSA) asserts that connected vehicle technology “can transform the nation’s surface transportation safety, mobility and environmental performance.” NHTSA is expected to start rulemaking on the connected vehicle later this year, which could result in a connected car industry mandate in the U.S. While it could take five or more years for final rules and several more years for rules to take effect, it would be a transformative event. “In six years, I expect to see vehicles widely using the technology,” said Scott McCormick of the Connected Vehicle Trade Association. “Vehicle manufacturers are eager for connectivity in vehicles, but need to understand the regulations that will be in play. This hasn’t been idle time, as vehicle makers are ahead of the game and have already embedded some connected vehicle technology into vehicles that can later be activated.”
The commercial fleet market has been the first adopter of connected vehicle technology as efficiencies provide cost savings, but the automotive market is poised to catch up. “Fleets now have access to actionable intelligence from the field,” said Andrew Maliszewski of Micronet, as well as an industry consultant. “Business decisions are now being made from data, including fuel levels, driver behaviors, vehicle performance, weather and traffic conditions, and even real-time trailer connect/disconnect events.”
Ownership of Data is Tricky. Some of the data that is produced inside a vehicle will be of great value to marketers. It will reveal personal information, including your driving habits, where you go, and how you react to in-vehicle marketing. David Jumpa of Airbiquity asserts, “There is uncertainty on who will own the data, but the sensory data, such as how you brake and accelerate, would be owned by the vehicle OEM.” When polled, many listeners of the webinar opined that content and app providers, and not vehicle OEMs or data infrastructure companies, will own personal data generated.
Making Money, or Not. The technology of the connected vehicle market hasn’t been easy, but it has been much simpler than finding the revenue models that will support companies in this market. “In the past, the vehicle market would use a tier-one manufacturer to deliver the entertainment solution, including maps and routing,” said Scott Sedlik of Inrix. “That isn’t the case now, and multiple suppliers work together and are also having to carry the risk that the vehicle OEMs had solely carried.” Some of the content and app providers are making money; others are figuring out the right business model. One of the questions that remain is whether the OEMs will pay for in-vehicle services and content. This is a pivot point of business, Sedlik adds.
Mobile App Marketing Cost at High. For brands that proactively market their apps, the cost of acquiring a loyal user increased in July to $1.80 according to Fiksu’s Cost per Loyal User Index. This is a jump of 30 cents from June, falling just a penny short of the December 2011 price of $1.81. Fiksu attributes the cost rise to brands leveraging Facebook’s mobile app ads, which target consumers based on app and games access on smartphones.
Mobile Map Usage. More than 60 percent of iOS users accessed Apple Maps at least once during the previous 30 days, reports Mobidia. That isn’t too surprising given that it comes installed on the phone. However, 20 percent of iOS users accessed Google Maps during the same period — impressive, since the user has to go to the effort of installing the software. Google Maps usage is heavy, although not as heavy as Apple Maps use. 55 percent of iOS users that use Google Maps, use it weekly; 80 percent of Apple Maps users use it weekly. Not bad, Google.
In the wake of Microsoft’s recent purchase of Nokia’s mobile phone business, the Nokia unit formerly known as Navteq, and now know as HERE, has opportunities, but also a hard-to-guess future. At least one industry analyst believes that Navteq/HERE was not included in the Microsoft deal because it was too expensive.
“While much ado has been made of the Nokia/Microsoft deal in the press, I was interested in why Mr. Softy did not acquire Navteq/HERE with the other assets of interest. There are several possibilities to explain this omission,” said Mike Dobson, TeleMapics president. “First, it could be the case that Nokia did not want to sell Navteq/HERE. Second, it is possible that Microsoft had no interest in acquiring its current map database supplier. Third, maybe the price for Navteq/HERE was too high. My vote is for number three.”
Dobson said that Nokia clearly would like to sell HERE, as it does not fit with the company’s profile, growth strategies, or competencies, on a going-forward basis. “Just as Navteq was not a good fit for Nokia in 2007, it is now a less comfortable fit for the reconstituted company, which is being focused on network infrastructure services,” he said. “Conversely, I suspect Microsoft was ambivalent about a deal that included [Navteq/HERE].” Under the proposed Nokia/Microsoft deal, Nokia’s mapping assets are to be licensed for a four-year term by Microsoft, which gives them time to firm up their future strategy for spatial data. Note that the price of the license for the mapping products was not part of the $7.1 billion transaction, Dobson said.
“Why was Mr. Softy gun shy? First, I suspect that Microsoft concluded that owning a mapping company was not core to any of Microsoft’s current initiatives, including its bumbling approach to location and connected car services,” Dobson said. “Next, Microsoft has enough problems competing with companies in its distribution chain, without adding another business that would serve to complicate its relationship with manufacturers and resellers. Of course, all of these objections could have been overcome if the price was right, it wasn’t, but that does not mean it won’t be in the future.”
Where Does Navteq Go from HERE?
Dobson says Navteq, Nokia and HERE are in a world of pain. “While the ‘new’ Nokia will have the ability to fund all of the development to enhance the Navteq database that it has deferred over the past five years, I think it is unlikely to do so. Nokia does not appear to understand the fundamentals of the location market, the automotive navigation market, or the connected car market,” Dobson said. “Perhaps most importantly, they have lagged Google in evolving their map compilation process into a modern, synergistic, information sourcing engine. The Navteq approach to crowdsourcing hinders their potential speed to market with updated map information and has allowed Google to reach parity with Navteq in some areas, while exceeding it in quality in other markets.”
The future battleground in the location markets will devolve into a scarp for ownership of the last mile, Dobson said. “The type of thinking that believes that the ‘last mile’ is all about road geometry, simply does not understand the problem. People want to know that the map will support their journey to a destination, but they are focused on the destination and the various opportunities that it presents,” he said. “For example, the mobile phone has promoted an egocentric view of the world focused on ‘what’s around me?’ Providing the spatial detail of the total environment that surrounds the user is key to winning the last mile battle and I do not see Nokia having the assets to participate in this market.”
Nokia announced that HERE, at the recent Frankfurt Motor Show, partnered with Mercedes Benz, Continental Corporation and Magneti Marelli to offer connected products and services beyond navigation. Nokia believes that connecting the car to the cloud is one of the biggest opportunities for the automotive industry.
“Whether the concept of the connected car offers Nokia a lifeline is unclear. Connectivity may suck the spatial data out of the car and into phone based systems,” Dobson said. “Others would argue that smart cars will require a detailed, highly accurate database of spatial information to manage the safety systems in the automobile of the future. I’m not wise enough to predict the future, but I think the Nokia is going to have a rocky road with Navteq/HERE.”
Dobson said that it is interesting that Microsoft has loaned Nokia 1.5 billion Euros in three tranches of convertible bonds. “The bonds will be redeemed and netted against the deal proceeds, although the loan is not conditional on the deal closing, nor is Nokia obligated to exercise its option,” he said. “However, it would appear that Mr. Softy and Nokia are not quite through with each other: if Nokia exercises these options, Microsoft will become a shareholder in Nokia.”
This year, ION GNSS+ was once again in Nashville, Tennessee — with around 1,050 attendees and 63 exhibitors, show attendance was down from last year, maybe because of a reduced military presence and more constrained government budgets. But the conference was a good one. The CGSIC (Civil GPS Service Interface Committee) ran just before the ION conference, and provided an opportunity for better visibility of the ins and outs of the GPS program and enabled a degree of U.S. military-commercial exchange.
On Tuesday, CGSIC gave us an overview of the Navigation & Timing exhibit at the National Aerospace Museum in Washington, D.C., an insight into news of the evolving U.S. government’s PNT policy, State Department international activities (including estimates of GPS contributing $68-122 billion and 3.3 million jobs to the U.S. economy), a Homeland Security update on interference detection and enforcement, and of course the regular GPS Directorate program updates from the Air Force. Then we had subcommittee reports from various sectors, including timing, survey, and from the Federal Aviation Administration (Distance Measuring Equipment, or DME, is apparently the FAA’s chosen back-up for GPS in the National Airspace System). Finally, the GPS Directorate chief engineer provided an overview of GPS R&D activities and an opportunity for civilian attendee feedback and input.
The lone commercial presenter — Eric Gakstatter, a fellow contributor to GPS World — proposed that the Air Force make “PRED” (predicted ephemeris, regularly produced by the Air Force GPS system, but not available to commercial users) be unclassified and released for civilian use.
Both Broadcom and Rx Networks commented that they provide predicted ephemeris to their users, and post conference I let Eric know that Baseband Technologies has a software product providing predicted ephemeris which is good for 28 days without any intermediate updates. The Air Force said it would think about releasing PRED, but there seemed to be significant issues to doing that.
The ION GNSS+ conference got going on the Wednesday morning, with a whole slew of technical papers, panel sessions, and the opening of the exhibition floor. The papers tend to be quite technical and sometimes quite academic — for example, “Approaches to Obtaining Beidou Hazardous Bias with Ordered Weighted Aggregation Operators” — but these quite detailed presentations is what a subset of ION GNSS+ attendees come for, and they want to hear the results of the very latest research. One “technical session” allowed manufacturers to provide announcements and summaries of their new products and systems — a welcome opportunity for commercial and technical attendees alike. ION has also instituted panel sessions, which deal with more global subjects — for example, Program Updates or High Integrity Systems (such as WAAS), which tend to draw equal attention from a good number of attendees.
The ION GNSS+ 2013 show floor.
The show floor always seems to be the highlight of the conference, however, and its often packed at times when papers or panels are not running. With around 63 exhibitors this year, it seemed a little smaller than last year, but there were also a number of new companies with booths.
Panel Sessions
Panel sessions I sat in on included Program Updates, some of New Products, and High Integrity Systems. Program updates were provided by GPS, GLONASS, Galileo, Beidou, and QZSS:
GPS URE (pseudorange inaccuracy due to ephemeris and clock errors) is running around 80 cm and was 47 cm at one time recently, versus a “promise” of 4 meters for civil users. The average age of the older IIA satellites (SVs) is currently running around 2-2.5 time design life, and as the newer generation of satellites (SVs) comes on line, URE is expected to continue to drop.
GLONASS is performing up to expectations and is relatively stable, despite the odd jump in URE which is apparently due mostly to ground control issues. The loss of three SVs in the July Proton launch failure was a setback, but with several SVs built and in storage, Russia anticipates resuming the replenishment schedule soon. They will get to orbit mostly using Soyuz launchers, and a few Protons. There is a commitment to launch new SVs with CDMA (time division format, as per all other GNSS) on L3, while maintaining existing FDMA (unique GLONASS frequency format) signals and, indeed, one GEO SV is apparently already on orbit transmitting an L3 CDMA test signal. GLONASS has the objective of achieving 60 cm URE by 2020.
Galileo is moving along with four SVs on orbit and initial fixes achieved with both commercial and government PRS signals; 22 FOC (production) SVs are now ordered, and 16 ground reference stations and five uplink stations stations are up and running. Significant effort is anticipated on the next phases of Galileo and EGNOS, and a €6 billion budget for this work has been approved.
Beidou apparently has 14 operational SVs right now, which is adequate for regional coverage of China, but work is intended to continue towards a global constellation of five GEOs and 30 non-GEO SVs. Work is also shortly intended on a Wide Area Differential Service, chipsets are already available for receivers, and site surveys are planned for offshore reference stations. A five-year plan has been approved, and the next launch is possibly in 2014 for testing of the global (MEO) constellation.
Michibiki cartoon.
QZSS has successfully proven the concepts of operation with the first Michibiki satellite, and Japan has ordered the remaining three SVs for the constellation. The ground network contact was also let in March 2012.The intention is to achieve sub-meter service on L1 C/A, and the CLAS augmentation system is targeted to provide a ~10 cm service.
The New Products panel had way too much academic and agency content for me and virtually no commercial new products content, so quite disappointing.
The High-Integrity (WAAS-systems) panel was much more interesting for a guy who used to live in this space:
WAAS has achieved LPV-200 (aircraft landing ~200ft decisions height) across the U.S., including Alaska in 2013, and RNP 0.3 (positioning within 0.3 nautical miles) across the whole of North America and a good portion of South America. Plans are moving forward with the introduction of L5 into WAAS. If Initial Operational Capability (IOC) for GPS L5 is 2021, then WAAS IOC for L1/L5 capability should be two years later — also replacement of obsolescent elements, and doubling the comms network bandwidth.
EGNOS has another Version 3 future evolutionary stage planned, with more RIMS (reference stations) planned, and possible expansion into Africa is on the table.
MSAS has not got to the operational accuracy it wanted yet, but with the current two MTSAT GEOS, RNP 0.3 is available over Japan and area. Ten more reference sites are needed to get to LPV-200, but there is no budget yet allocated.
Gagan now has two GEOs (GSAT-8 and 10) and achieves RNP 0.1 over India and anticipates operational certification by 2014.
SDCM (Russia) is anticipated to be in place by 2016 for L1, and by 2018 expects to add L5. Currently working some interference issues between the second SDCM GEO (Luch-5B) and an Inmarsat GEO at 15.5 ̊ West, the contact for the SDCM ground network is anticipated before the end of this year, and a heavier (five-ton) GEO (called Enisey) is planned for the 95 ̊ Eastslot in 2017/18. This will carry not only L1, but also L5 and L3, both CDMA signals. There was a lot of interest at ION in when the GLONASS CDMA L3 signal would be fielded in the GLONASS constellation — no real predictions for when, but the L3 ICD release should be “before the next GLONASS K launch.”
Exhibit Hall
The exhibition was indeed a little smaller than last year, but there was plenty of activity on the floor. Most people I talked with had new products at the show, or had new information they were eager to discuss:
STIM300 MEMS Sensor.
Sensonor (Norway)has joined up with NovAtel,who is now offering its STIM300 MEMS inertial sensor as part of the NovAtel SPAN family. Sensonor apparently has a number of installs on unmanned aerial vehicles (UAVs).
Sysnav (France) has a sensor that cleverly uses Magnetic Variation with MEMS to do fairly accurate positioning in the absence of GNSS signals. Sysnav was looking for partners in North America.
Javad had his usual extensive line of surveying instruments, but his latest OEM receiver showed up with 864 channels! With three processors, program memory, multi-constellation (everything!) and monster channel tracking (100 of which scan for GNSS interference), this by far had the greatest receiver capacity at the show.
Trimble announced its latest tiny BD930 RTK capable OEM receiver — supporting both triple-frequency GPS and GLONASS, plus dual-frequency Beidou and Galileo. And it’s completely enclosed in an RF screening “can.”
ComNav (China) showed up with a series of multi-frequency, GPS/Beidou/GLONASS RTK-capable OEM receivers, packaged receivers, and antennas. With 100 people based in Shanghai, ComNav claims to have captured 30% of the Chinese market, selling 15,000 receivers — derived from technology developed by Dr. Wong Yong Quan. Impressive capability on display — also seeking distribution in North America.
Surrey Satellite (UK) are apparently working on a number of R&D projects alongside building the nav payloads for the Galileo FOC SVs. TechDemoSat-1 is an innovative UK technology platform that includes a GPS reflectometry experiment to measure wave intensity for marine weather services. Apparently there is little weather information for large areas of the world’s oceans, and this may help to solve a major marine nav issue.
Nottingham University (UK) is working on predictive integrity for UAVs. GNSS signal outage/degradation in flight, caused by antenna obscuration, multipath, fading due to adverse geometry and Doppler shift, are critical for UAVs. Nottingham modeling is aimed at real-time avoidance of safety-critical flight conditions and fast recovery of navigation performance following GNSS data losses.
Trusted Positioning (Canada) is moving quickly down the indoor location path and has some neat software integration solutions for cell phones using signals of opportunity, pressure sensors and MEMS. The company sees the initial market being for things like mapping indoor locations, iteratively improving positioning, and location-based advertising.
Spirent GSS6425 record and playback system.
Spirent has released the GSS6425, which is a highly portable simulation system for recording live GPS L1/L2/L5, GLONASS L1/L2/L3, BeiDou-2 B1/B2, Galileo E1/E5, QZSS L1/L2/L5 and SBAS signals in the field — for repeated replay in the lab. BeiDou has been introduced across the Spirent simulation product line, and Spirent released information on sophisticated spoofing simulation.
IFEN (Germany) is also working on spoofing, has added BeiDou B1 and B2 signals, has added a four multi-RF output capability, and is working on automotive gyro and odometer testing capability.
R&S DDF007 Portable I/F Direction Finder.
Rohde & Schwarz had an extensive display of capability alongside its SMBV 100A GNSS simulator. An impressive array of spectrum analyzers and generators, with one set-up catching my eye — the DDF007 portable interference detection system used by government agencies for tracking down jammers.
I didn’t get to everyone’s booth, and I just didn’t have the space to cover everything, but I’d call this a reasonable cross section of the exhibitors; to some degree its a summary of the panels and includes some of the corridor discussions typical of ION.
So, I would call this another successful ION show, and I’m looking forward to next year’s ION GNSS+ conference in my neck of the woods in Tampa, Florida, in September. It would seem that the interest level remains high across academia, agencies and industry — but those of us who may still want to see new business as payback for the investment of attending and/or exhibiting, I think we would have preferred still more commercial content.
ION remains a place to meet and greet customers and people working across multiple market segments, where system providers can brief us and mix with users, and the intensity of technology development and research can be shared and sampled. It’s still an invaluable place to visit once a year if you are connected in any way to the GNSS industry and community.
It was a dark and stormy night. The winds gusting to over 70 miles per hour drove the snow horizontally, straight into Lynn’s headlights, making it almost impossible to see the road. The outside temperature was -20 degrees Fahrenheit and the roads were treacherous. Lynn wondered for about the hundredth time what he was doing in the foothills of the Rocky Mountains in the middle of a blizzard.
Certainly the day had started innocently enough with several key meetings in Washington, D.C, where Lynn had been for the entire week, and he could not wait to get home. After the last meeting, he made a dash to Reagan National Airport with visions of a quick three-hour flight to Denver and then a short trip south and home to the Rocky Mountains. That’s when things first went sour.
Any seasoned traveler who routinely passes through the D.C. area knows that Reagan National is by far the most convenient airport, but the international Dulles airport is by far the most dependable. Unfortunately, Reagan shuts down for hours with the first raindrop or snowflake, and as luck would have it, a major winter storm slammed into Reagan about the time Lynn arrived, and the flight to Denver was delayed, incrementally of course, for over six hours. The only upside was half the passengers gave up after a couple of hours of repeated 30-minute delays and decided that traveling on Saturday morning was the preferred option.
But not Lynn — oh, no — having spent a great deal of time in airplane cockpits he managed to finagle a conversation with the stranded flight crew, and discovered that the aircraft in question “had” to be in Denver (DEN) before 0500 the next morning for a flight to Seattle, and then on to Anchorage later Saturday morning, so no matter what, the aircraft would eventually get to DEN. So he waited. Sure enough, the 6 p.m. Friday flight finally departed Reagan at 1:15 Saturday morning and arrived in DEN at 2:15 Mountain Standard time.
By the time he woke up the car park personnel and convinced them, with an extra $20 bill, to brave the weather and transport him to the parking lot in Outer Mongolia, where his trusty Audi awaited, it was just after 3:00 a.m. Thus he began his journey south, in a raging blizzard. But he wasn’t concerned because wasn’t his new Audi Q7 Quattro the best four-wheel drive in the world, bar none? At least, that’s what the brochure at the dealership claimed, and Lynn had every confidence his trusty steed would find the barn. What he had not — and indeed could not — have predicted was the incredible knifing pain that struck at about 4:30 a.m. as he was just coming into North Colorado Springs. The sudden excruciating pain seared through Lynn’s leg, and he seriously thought for a moment that he might black out. Indeed, the sudden pain immediately brought back memories of a wound he had suffered in a godforsaken part of the world to the same leg many years before, but unless there was an invisible Viet Cong gunman in his passenger seat, this pain was from another source and it was, if possible, getting worse not better.
So what do you do at 0430 on a Saturday morning in the middle of a blizzard, on a deserted highway, when you are in excruciating pain? Lynn’s first thought was to dial 911, and that was certainly a possibility, but how and when would someone locate him? Mile markers were obscured with snow and the odds were not good. Plus, if the source of the pain was a blood clot brought on by hours and hours of inactivity exacerbated by three hours of sitting in an uncomfortable airplane seat — then he might not have much time. Lynn had heard the occasional apocryphal story of blood clots on airline flights, and the outcome was not always a good one. Supposedly, once a blood clot breaks loose and reaches your heart, lungs or brain, you are pretty much toast. Great, Lynn thought, here I am in pain, slightly panicked by my own imaginings and still in the middle of a blizzard on a lonely highway in the Rockies at 0-dark-thirty with not a clue what to do.
Then it came to him: GPS! He pushed the destination button on the Audi’s built-in GPS unit and dialed down to the “Emergency Locations” tab on the display, pushed the button again, and was immediately rewarded with the choice of the nearest:
Hospital
Emergency Room
Service Station
Fire Station
Police Station
Lynn frantically pushed number one. A female voice boomed forth and notified him that the nearest hospital was only three miles away, and he should take the next exit, which was just becoming visible through the blizzard. Lynn took that exit and within five minutes was in the emergency room of Memorial Hospital North. And since the GPS also gave him the phone number of the emergency room at the hospital and asked if he wanted to dial it, he did. He told the nurse who answered about his sudden leg pain and that he was only minutes out. Lynn was met in the emergency room parking area and placed in a wheel chair. An orderly took his car and parked it, and within about five minutes the excellent medical staff confirmed his worst fears and determined that he did indeed have a blood clot. Massive blood thinners were introduced into his system, and they obviously worked, as he is here today telling his dramatic life and death story to anyone at the Audi dealership who will listen. But it actually becomes a bit more melodramatic; the doctor on call was a cardiac specialist, pulling his emergency room rotation, and he informed Lynn that another ten minutes and it would probably have been too late. Indeed when the medical technicians first imaged the blood clot, it was already on the move, and they just managed to dissolve it before it reached something vital.
The cardiac doc said the only other alternative would have been emergency surgery, which there was not time for, or threading a catheter through a major artery and hoping to find and grab or dissolve the clot before it did any major damage. Obviously, someone on high was looking after Lynn that night. But it also occurred to him as he lay in the emergency room and later in the ICU for follow-up treatment that most likely his GPS and his knowledge of its additional functions had saved his life. According to the doctor, it had certainly saved him from the consequences of a major stroke. All because he had taken the Audi dealer’s advice and spent a few minutes from time to time with the Audi Users Manual, learning about the integrated navigation system and exactly what it was capable of accomplishing when used properly.
Like many advanced automobiles today, the navigation system in the Audi incorporates GPS and wheel sensors with the mapping system, POI (points of interest) database, Internet, Google Maps, 3D maps, Google Streets, radio for traffic and weather updates, and of course the telephone for automatic calls to restaurants to reserve a table or, as in Lynn’s case, to a hospital emergency room for life-saving information.
Fast Forward to Today
This story was brought to mind this Labor Day weekend by events that transpired as my wife and I journeyed south of Colorado to her adopted hometown in the southern part of New Mexico. Like Lynn, we were also in an Audi Q7, in my opinion one of the most comfortable cruising venues you can purchase today, when we came upon a familiar and much-needed service station in the middle of “nowhere” New Mexico, only to discover that while the bio break was possible, fueling the Audi was another matter entirely. It seems the modern-day pumping apparatus requires an Internet connection to validate credit cards, and that system was “temporarily” unavailable. And who carries around several hundred dollars in cash for gasoline purchases today, just in case? For those of you who know what “temporarily” means in New Mexico, you will understand why I immediately began to worry. Even if the pumps had started working at that moment in time, we would have been there for several hours just waiting our turn, and who knew how much gas was in the tanks at the service station and when the intermittent Internet connection might go down again? Our options were to backtrack 100+ miles, or press on and hope for another service station or drive at the most economical speed — for best miles per gallon — which my Audi info system dutifully informed me was 52 miles per hour, and just pray that the fuel quantity sensors were correct and we might just make it to our destination.
However, in a flash of intuition I remembered Lynn’s dealership story. I pushed the “Emergency Services” button and selected the option for the “nearest service station.” Amazingly the system did not select the “out-of-service” station we had just departed, but another one 32 miles closer to our final destination that neither my wife nor I could ever remember seeing before in a tiny village of no more than 100 people. Faith springs eternal, and we were on our way. Sure enough, in about 25 minutes we were fueling the thirsty Audi at a brand-new Phillips station that I swear had not been there during any of our previous sojourns through the blink-and-you-miss-it village. Now, it may not have been a matter of life and death, but who wants to run out of gas in the middle of New Mexico on a 100+-degree day in an area with little if any cellular service? Certainly not yours truly.
My purpose in relating these two vignettes, as humbling as they may be, is directed primarily at the macho types reading this article. Sure, you know who you are, the type that proudly boasts you have never read an instruction manual in your life. The kind of guy or gal that refuses to ask for directions. Well I am here to tell you that when it comes to your GPS — indeed, your hopefully integrated automotive navigation system — get out the book and read it and become intimately familiar with your PNT system, whatever type it may be. It could just save your life.
And before you start that old yarn about, “If I have to read the manual, then it is not user friendly and I won’t use it,” consider the consequences of, friendly or not, being unable to use the system in a real emergency. Even the portable Garmin units that most of us cut our teeth on are integrated to an incredible extent today. It may only seem to plug into your cigarette lighter or, to be more politically correct, your auxiliary power port, but in truth the Garmin and many other portable PNT devices may well be connecting to your mobile phone and your radio for traffic and weather updates. Plus, most of the higher end Garmin units today have an incredibly detailed database with phone numbers and hours of operations for many businesses and, yes, they also have the “Emergency Locations” tab and will guide you to the nearest hospital, give you the phone number for the emergency room, possibly even dial the number, act as a speaker phone and even direct you to the next service station. There’s even a Garmin unit today that will project a heads-up display on your windscreen or windshield.
And unlike your wife or significant other, your GPS will do so without saying, “You were supposed to turn left back there” or “I told you so!”
All major international car-makers are installing telematics units, sending a signal that wireless information and connectivity is here to stay in the vehicle, and location will be a big part of the growth. To learn more about the rapid changes in the connected vehicle field, tune in to our September 19 webinar, hosted by Wireless LBS editor Janice Partyka. Registration is free.
What Is Don Reading?
This month I will quickly review two books that I hope you will find interesting.
Sniper Elite: One Way Trip A novel by Scott McEwen with Thomas Koloniar
Obviously, this very technically correct book is about snipers, and that means it includes data on Seal Teams and Delta Force. But more importantly, this novel puts forth a warrior’s perspective of women in combat, and the actions taken by their fellow comrades in arms to keep them safe and rescue them if necessary. Indeed, the whole story revolves around Seal Team Six and Delta Force fighters that are deployed to free a captured female helicopter pilot from the 160th Special Operations Aviation Regiment (SOAR) — in other words, one of their own — who is being held, interrogated and brutalized by Taliban insurgents in Afghanistan. Throw in D.C. political intrigue and a president running for re-election who has his own opinions about women in combat and you have a real page-turner.
GPS capabilities and units are mentioned throughout the book, and referred to when it is absolutely critical that warriors know exactly where they and their targets are located. It is clear that entire missions would be lost without the capabilities that GPS enables.
It is a gripping read that grabs you from the first page, and again, it is tough to put down. It is even good enough that you might want to read it more than once. And yes, if this sounds familiar, both McEwen and Koliniar wrote the #1 New York Times bestseller American Sniper, which I also highly recommend.
Ike’s Spies: Eisenhower and the Espionage Establishment An historical biography by Dr. Stephen E. Ambrose with an introduction by Douglas Brinkley
The historians among you should recognize Dr. Stephen Ambrose’s name and associate him with perhaps the most prolific chronicler of our day concerning the life and times of President (General) Dwight David Eisenhower.
Dr. Ambrose, a renowned historian, authored more than 30 books in his lifetime and more than half of them concerned Dwight David Eisenhower during some key period of his life.
The film rights to two of his more famous books were purchased by Steven Spielberg and Tom Hanks, who used Citizen Soldiers and Band of Brothers to make the 13-hour HBO mini-series Band of Brothers.
Dr. Ambrose once described his writing style: “As I sit at my computer, or stand at the podium, I think of myself as sitting around the campfire after a day on the trail, telling stories that I hope will have the members of the audience, or the readers, leaning forward just a bit, wanting to know what happens next.” And this is just the style that makes this history a page-turner. Even though you may know the outcome of the historical event, it is the insider’s view that makes this book such a fine read.
Until next time, happy navigating, and read a good book — but first get out your GPS device owner’s manual or look it up on your iPad or computer for video tutorials, and peruse them for awhile. It could save your life one day.
$2,000 for an RTK base and rover? Yes, it’s real. Well, at least it seems real.
For $2,000, you can order an RTK base and rover set named Piksi, including radios.
It’s an intriguing opportunity, and might be the first brush stroke of the picture I’ve been painting (metaphorically speaking) for the past few years about inexpensive RTK receivers forthcoming. But, before you get really excited, read on.
Besides the attractive price, something else that makes Piksi interesting is the way the company is financed. The way that a typical company funds new product development is through its own cash flow or financing. The company designs and produces a product, then announces it to potential buyers (you), who then touch, feel and use the product to understand how it performs…all before making the decision to purchase. Piksi (Swift Navigation) doesn’t follow that model.
Piksi is using a new-age, crowd-sourced funding model called Kickstarter. With Kickstarter, a group of people (creators) offer to design and produce a certain product if they can recruit enough “investors” to fund their endeavor. The “investors” aren’t traditional venture capitalists, nor people who would own stock in said company. The investment is simply a commitment to buy the product based on the specifications provided by the creators, before the product is finished. If the company has enough commitments from “investors,” the creators commit to designing, building and delivering the product.
Furthermore, there are certain levels of investment available for Piksi, from $7 which will get you a Swift Navigation micro-USB cable, to $2,000, which will get you a ruggedized version of the complete RTK kit, including base, rover, XBee radios, Bluetooth and SD card storage. So far, Swift Navigation has raised $161,369 towards the project with today, September 4, being the last day. That’s far more than the $14,000 goal it set.
The caveat is that the product is not complete yet, at least the RTK portion. According to Swift Navigation:
We have already built a small batch of Piksi receivers that are ready to ship and have locked down all part sourcing and manufacturing for further batches, so there are unlikely to be any unanticipated delays in the delivery of Piksi hardware.
However, it’s difficult to know exactly how long the RTK functionality will take to implement — software development schedules seem to always run over their anticipated delivery dates, even when you take into account Hofstadter’s Law. We feel the goals we’re proposing to accomplish with this campaign are reasonable — adding a new set of software functionality (which we successfully implemented on a previous platform) upon an existing base of stable hardware and software.
The gamble that the investor takes is that Swift will be able to finish the product, produce it, and meet the performance specifications. However, that’s only part of the battle. I spent better than 10 years of my life managing the design and production (somewhat) of GPS-based hardware and software for mapping and surveying. There are a million details. A major part of developing a hardware/software product like this is making it reliable. What I mean by reliable is that it behaves the same way every time you push the ON button, and works consistently and reliably all day until you press the OFF button. That’s not easy to achieve without a lot of sophisticated testing in different environments, and nothing can fix a poor reliability design (except a redesign).
The guys behind the Piksi don’t seem to be total GPS-rookies, but do lack substantial real-world experience. Click here and then click on Bios to read about their backgrounds. But who knows? Maybe that’s an advantage, not being conditioned to “follow the rules.”
One last note, and an important one. It’s only an L1 system, so don’t get too excited. L1 means that you really can’t use an RTK network (practically speaking) and that the baseline distance needs to be pretty short. The RTK initialization and re-initialization times will be measured in minutes, not seconds, and that’s assuming they get the RTK algorithms correct (and reliable).
Sorry to burst your bubble.
Actually, the concept of an inexpensive, bootstrapped L1 RTK system is not difficult to envision. The GPS OEM boards are readily available, as well as the GPS antennae, wireless comms and the rest of the components. At the risk of sounding pompous, I could put that kind of project together. The trickiest part of the project would be developing/implementing reliable RTK software.
No matter what, it will be interesting to hear about what these guys come up with. In the words of the late Steve Jobs, “stay hungry, stay foolish.”
GPS jammers are cheap, but don’t get caught using one.
Even though they are illegal to market, sell and operate in the U.S., Americans are buying cheap GPS jammers, via Internet stores, from companies operating outside of the U.S. Operating one of these devices in the U.S. is a risky venture (as you’ll read below).
Although they don’t seem to be a serious threat yet, they could become a threat as GPS receivers become more ubiquitous and concerns about privacy continue to ramp up.
The Federal Communications Commission (FCC) is responsible for enforcing the U.S. laws enacted that prohibit the use of GPS jamming devices. If you look at the FCC’s enforcement history here, you’ll see that there isn’t much enforcement activity. However, a recent enforcement action was imposed on a guy in New Jersey who made the mistake of driving by the Newark International airport with his GPS jammer turned on. Uh oh. The FCC tracked down the offender and issued a Notice of Apparent Liability for Forfeiture that included a fine of nearly $32,000. Whoa, that’s a lot of dough. Wonder if he is trying to sue the company he bought it from? Not likely, as they are most certainly outside of the U.S. and out of reach of the U.S. judicial system. Caveat emptor.
You can be assured that if jamming reports increase, there will be more jamming detection and location equipment deployed to hold people accountable, like this new, handheld GPS jammer detector and locator from Chronos:
You might want to visit this GPS.GOV website on GPS jamming. It contains a lot of information about the U.S. regulations surrounding the marketing, sales and use of GPS (and cell phone) jamming devices.
Third annual Field Technology Conference
In 2010, I, along with two colleagues, put together a conference here in Portland, Oregon, and named it the Field Technology Conference. We created the conference to focus on geospatial technology hardware and software used in the field. It’s the essence of what a conference should be, a group of people gathering to share ideas of common interest. It’s mostly devoid of commercial interests, save a few really neat (and valuable) giveaways and a few exhibit booths. You probably haven’t heard about the conference because we have a very small marketing budget, and the organizers (three of us) can only spend a few hours a month brainstorming, finding speakers, and organizing the event.
This year, our third, will focus on existing and emerging technologies: GPS/GNSS, UAVs, 3D printing, mobile devices, imagery and geospatial software. Our outdoor demonstration area was very popular last year so we’ll offer that again, as well as a UAV demonstration. We’re also planning an on-site demonstration of 3D printing. Can you imagine 3D printing a topographic survey?
Something new this year is our association with the CGSIC (Civil GPS Service Interface Committee). CGSIC is co-locating a regional event with our conference. What that means is that speakers from the U.S. government (Air Force, State Deptartment, DOT, etc.) will make GPS-centric presentations. CGSIC events are the only live communication channel between the U.S. Air Force GPS operations personnel and civilian GPS users. This is your chance to ask Air Force personnel questions, in person, that you’ve always wanted to know about GPS. If you’re unable to travel to Portland for the conference (October 23-24), GPS World magazine is planning on streaming the CGSIC presentations live over the Internet, as well as posting the recording on its website.
Although the conference is organized by the Western Forestry and Conservation Association (which organizes a lot of conferences), take a look at the agenda and you’ll see the content will be of interest to anyone involved with geospatial data collection and processing technology, not just foresters and environmental scientists. For conference details, click here.
Two weeks ago, I attended a USGIF workshop in Huntsville sponsored by GEO Huntsville, through the considerable efforts of Directions Magazine Editor-in-Chief and Vice Publisher Joe Francica and his staff. The United States Geospatial Intelligence Foundation (USGIF) is a non-profit dedicated to promoting the geospatial intelligence tradecraft across industry, academia, government, professional organizations and individual stakeholders.
GEO Huntsville’s Geospatial Intelligence (Geoint) Workshop was held August 14 at the Von Braun Center Civic Arena in Huntsville, Alabama.Keith Masback, USGIF chief executive officer.
The workshop was a collection of geospatial-related presentations starting with Keith Masback, the USGIF chief executive officer, who gave an interesting history of NGA based on his extensive experience in the geospatial community. He reviewed that NGA had a somewhat shaky start that grew out a vision of Rear Admiral Bill Owens, which was part of the 1996 “Joint Vision 2010” that formed the concept of network-centric operations. Looking at the past, the Joint Vision participants saw that the future would require a new way of doing intel business. They determined that information had to be brought near the user, not at some distant command center. It would need to be as close to real time as possible. It would have to be precise and able to ID combat targets. It would have to be integral with missile defense and provide detailed urban data.
So in 1996, the NIMA (National Imagery and Mapping Agency) was formed by combining the DMA (Defense Mapping Agency) and the CIO (Central Imagery Office). The merging of mapping and imagery communities proved very difficult as the two cultures collided. Even the internal NIMA commission was bent on dissolving the marriage. Fortunately, after working through the issues, the commission came to the conclusion that the marriage was really in the best interest of the country and both communities.
It was also at the same time that Jim Clapper took over the week of 9/11. That event sharply focused everyone’s minds. General Clapper decided that the best way to unify the command was to get rid of the separate words “imagery” and “mapping” — thus was born the new title National Geospatial Intelligence Agency, and to put it in the same company of other three-letter agencies, it was dubbed NGA. NGA really worked hard to meet the vision set in 1996. Keith cited the Bin Laden apprehension as a good example.
He then explained how NGA felt it needed to evolve. He cited the example that our troops needed to be as location enabled as kids are with their mobile devices. Crowd sourcing is playing an ever-increasing roll, and despite the belief that the cyber world is locationless, location is a very real aspect of cyber warfare. Users have locations as well as servers and the interconnecting framework. Asymmetrical urban warfare demands even more precise location mapping, including building interiors. Keith cited Robert Scoble’s keynote at The Next Web Conference Europe as a must-view video by everyone in the geospatial community, to place his comments in context. Robert Scoble and Shel Israel are going to be keynote speakers at GEOINT 2013.
Additionally, although the military is taking a lion’s share of sequestration cuts, the two areas that are not seeing significant cuts because of WMDs are ISR (intelligence, surveillance, and reconnaissance) and cyber. He said that some people question the need for geospatial capabilities in a cyber world, but he quickly cited that servers have locations, that networks have locations, and most hackers/persons of interest have locations, which also point to the growing need for indoor urban tracking of users. And all this takes on even more significance with the proliferation of WMDs. Although not as immediate, NGA is also very supportive and promotes STEM (science, technology, engineering, and mathematics) education so we maintain the pipeline of talent. He also talked about the growing drumbeat for geospatial intel certification, especially for contract work.
Randy Jones of the Missile and Space Command spoke of the much shorter timelines of intelligence and needed action, that we have a flood of information but have a poverty of attention. That there is a growing need for “object-based intelligence” or, as some refer to it, “activity-based intelligence.” The flood of data is overwhelming analysts, and NGA is looking for increasingly sophisticated algorithms to sort the massive data collections. The are many opportunities for small, innovative companies in this arena to help DIA, NGA, and NSA.
Robert Zitz of SAIC gave his take on current actions in Washington. He quoted James Clapper as saying, “We’ve run out of money, so now we have to think.” He also cited Latisha Long that although DoD was seeing 5% sequestration cuts, DHS may see increases to its budget due to WMD and cyber concerns, specifically power, water and transportation. (As a side note, I harp to all my family members and friends the need to heed the DHS warning for all citizens to maintain a two-week supply of food and water in their home.) There is also special attention being given to joint efforts of special operations, cyber security and border security. Those intel dollars are increasing especially for real-time data collection, multi-int fusion and predictive analytics.
A representative from Sierra Nevada and L3 talked about wide area air surveillance (WAAS), specifically Gorgon Stare and the domestic manned aircraft version Vigilant Stare, which is also being linked with full-motion video. The key issue is analytics to filter and provide timely actionable intelligence.
MIC cameras from Bosch Security Systems feed a Coastal Remote Monitoring Program for the Alabama Department of Conservation and Natural Resources.
A very clever use of lower cost, off-the-shelf hardware to solve a critical need was presented by Major Scott Bannon of the Alabama Marine Resources Division and Tim Erwin of Crystal Data International. Major Bannon’s small staff is tasked with monitoring more than 600 miles of Gulf Coastline. They installed a network of ruggedized video cameras, some in very remote locations, that were connected via a wireless network with all the cameras controlled by the users. This is not much different than many systems seen in urban areas, but the challenge was building a rugged system with some very remote locations lacking power or connectivity. The cameras were geo-referenced on Google Earth and controllable by his staff from mobile devices. Although the images are not directly geo-referenced, their position coupled with user knowledge permitted them to search and identify objects in the water accurately enough to task rescue assets to craft in distress. The night low-light imaging capability helped in several high-interest events. A new version will provide accurate azimuth data recorded with the imagery.
Dr. Michael Botts presented his work to develop common standards for web enablement of sensors. SML (Sensor Markup Language) is being backed by the OGC to permit sensor web enablement (SWE). See the OGC website for more details.
The workshop was closed by Sandra Broadnax, the NGA Small Business Programs director. Her presentation was probably the best received session because of her infectious enthusiasm. She explained how NGA Director Long was extremely supportive of small business innovations and contributions to the intelligence community. She explained how NGA maintains a very comprehensive list of changing requirements on both the high and low sides. She strongly encouraged all geospatial firms to monitor the NGA site, since there were many opportunities that are not published in FedBizOps. At the session she wasted no time building connections by identifying those who had SCIFs in Huntsville and those who might need access so they could view and respond to classified requirements.
So, the key topics that I believe will dominate GEOINT 2013 are:
Persistent wide area air surveillance
Social media, big data, human geography
Every individual a consumer and provider of intel data
“Object” or “Activity” based intelligence, even inside buildings
Integration of real-time actionable intelligence to users in the field
The geospatial links of cyber threats
As you can see, even in the short span of one year, the geospatial community continues to evolve significantly. I’m going to attend GEOINT 2013 in October and the GaTech Research Institute GIS conference Spatial Plexus in November. If you see me, please introduce yourself.
From left: James J. Miller and John LaBrecque, NASA Headquarters; A.J. Oria, Overlook Systems Technologies
By James J. Miller and John LaBrecque, NASA Headquarters, and A.J. Oria, Overlook Systems Technologies, Inc.
Satellite laser ranging (SLR) and the results of combining SLR with GPS in the future will translate into significant performance advancements for generations to come, once it is fully implemented as part of the GPS III architecture. Simply put, SLR techniques will improve GPS signal performance by enhancing the accuracy of GPS orbit and clock estimates, allowing for the correction of systematic errors and limitations inherent in current GPS radiometric solutions.
This will produce higher levels of positioning and timing as new information is processed and used to update orbital models and reference frames over a period of time. Eventually this will enable user accuracy in the centimeter range, orders of magnitude better than the 1-meter average user-range accuracies accessed today. Every GNSS constellation under development will provide for SLR, because not doing so would limit their systematic accuracy and diminish the potential of their PNT services.
This SLR initiative progressed over the past decade from technical engineering exchanges to senior-level reviews and policy deliberations under the aegis of the PNT EXCOM (see Sidebar), with GPS III now poised to have laser retro-reflector arrays (LRAs) placed on board all space vehicles, beginning with number 9 (GPS-III-SV9).
The National Aeronautics and Space Administration (NASA), National Geospatial-Intelligence Agency (NGA), National Oceanic and Atmospheric Administration (NOAA), and the U.S. Geological Survey (USGS), among others, strongly support the decision by Air Force Space Command to proceed with the placement of LRAs on board GPS III satellites to enable SLR. These agencies will work together to ensure that the derived science benefits all PNT EXCOM agencies and our many constituents and users around the world.
How Satellite Laser Ranging Works
SLR to any orbiting body involves firing repetitive laser pulses towards an object equipped with some form of LRA. The laser roundtrip time is then translated into distance or range measurements (Figure 1). In our case, SLR data collected from lasing to GPS and other GNSS constellations is compared with radiometric data collected at GPS/GNSS ground monitoring stations.
Figure 1. SLR operations description.
Radiometric monitoring and SLR each have their respective strengths. Radiometric monitoring stations are inexpensive and can be densely deployed, but are susceptible to systematic errors that cannot easily be identified. SLR is a high-accuracy method, independent of radiometric positioning, that can be used to identify some of these systematic errors. The two techniques in concert will provide more accuracy to the determination of satellite orbits and clocks, strengthening the societal benefits of GPS through improved performance and more precise applications over time.
Societal Benefits of Space Geodesy
Geodesy is the science of the Earth’s shape, gravity, and rotation, and their variations over time. Modern geodetic measurements rely upon GNSS technology and techniques to understand and respond to evolving geo-hazards such as earthquakes, volcanic eruptions, debris flows, landslides, land subsidence, sea-level change, tsunamis, floods, storm surges, hurricanes, and extreme weather. In recent years, GPS radio occultation data from satellites is used by weather services to improve the accuracy of forecasts. Other benefits include the use of regional differential networks to monitor crustal movements in near real time, and guide farm machinery and construction equipment with centimeter-level accuracies.
An essential element is the ability to relate geodetic measurements to one another in space and time through a stable and accurate reference frame. Most global terrestrial reference systems set their origin to the Earth’s center of mass or geocenter. Precise knowledge of the reference frame geocenter and its relative change are needed to study regional and global sea-level fluctuations and ocean-climate cycles like El Niño, the North Atlantic Oscillation, and the Pacific Decadal Oscillation.
Reference Frames
GPS satellite ephemerides are derived from ranging based on pseudorandom noise signals and carrier-phase variations, referenced to onboard atomic clocks and a ground network of GPS monitor stations expressed in the World Geodetic System 1984 (WGS 84) reference frame. The WGS 84 reference frame is determined using the analysis of GPS satellites, and must be periodically updated by the National Geospatial-Intelligence Agency (NGA) due to geophysical processes such as tectonic-plate motion. NGA works to maintain the tightest alignment between the WGS 84 and the International Terrestrial Reference Frame (ITRF) using GPS reference sites common to both.
The more ambitious ITRF is obtained using a global network of instrumentation — GPS, SLR, Very Long Baseline Interferometry (VLBI), and Doppler Orbitography and Radio-positioning Integrated by Satellite (DORIS) — and geodetic satellites such as LAGEOS and LARES. These data are gathered and analyzed through an international cooperative effort by the services of the International Association of Geodesy (IAG) within the framework of the Global Geodetic Observing System (GGOS) (Figure 2).
Figure 2. Structure and products of the Global Geodetic Observing System related to GPS performance.
The integration of SLR and radiometric tracking of all GNSS constellations will improve multi-GNSS performance and interoperability as tools and techniques are co-located and data combined into various products that enable PNT service providers to improve system models.
Geodetic Requirements. GPS is a critical component in the determination of the ITRF geodetic reference frame and serves as the principal means of positioning relative to the reference frame. Though the current accuracy of the ITRF and WGS 84 reference frames marginally meets most current operational requirements, emerging scientific requirements in Earth observation demand more accuracy than core geodetic systems, including GPS and the ITRF, can deliver.
There is thus a growing GPS capability gap that can only be met with systematic improvements such as SLR will enable. In this manner, today’s scientific needs for positioning and timing often become tomorrow’s operational capabilities. If GPS is to continue as the primary geodetic reference system, we must ensure that GPS continues to evolve its system accuracy as well (Figure 3).
Figure 3. Evolution of GPS accuracy versus civil and scientific requirements assuming a factor of ten per decade improvement in accuracy.
Presently, the accuracy of both the ITRF and the WGS 84 is estimated to be on the order of 1 part per billion (6.4 millimeters at the Earth’s surface), with observed regional drifts on the order of 1.8 mm/year, and errors in the colocation of geodetic stations exceeding 5 mm/year. There is also little to verify this estimated accuracy of the reference frames, because successive estimates of the ITRF are retrospective and utilize the same historical data sets, except for the addition of more recent data and new analysis approaches. All determinations of the ITRF are therefore inter-related and not independent, allowing some errors to remain embedded.
Although such drifts and errors are acceptable for meter-level positioning, we must address these significant instabilities if we are to meet the growing geodetic requirements demanded by science and society. The GGOS and the National Research Council have called for a significant improvement in the accuracy and stability of the ITRF, including the goal for 1 mm of accuracy and 0.1 mm/year of stability.
Getting Laser Reflector Arrays aboard GPS III
In 2006, a working group of representatives from multiple U.S. civil and military government agencies identified a set of anticipated geodetic requirements for GPS to meet future geodesy and science needs. An analysis of alternatives (AoA) concluded that the only practical solution to correct for systematic errors in satellite coordinates and reference frames is optical laser ranging, as has been demonstrated on board GPS block IIA SV-35 and -36. These were equipped with LRAs thanks to the effort of Ron Beard of the U.S. Naval Research Laboratory (NRL).
In 2007, the geodetic requirements and AoA were submitted to the GPS Interagency Forum for Operational Requirements (IFOR), along with formal endorsement letters from NASA, NGA, NOAA, and USGS. The goal of the GPS IFOR is to ensure that new features on GPS adhere to U.S. PNT Policy objectives, and that any proposed technical enhancements do not degrade core GPS performance, schedule, signals, or services. Between 2007 and 2012, interagency IFOR discussions and studies continued and subsequently were elevated to a special multi-agency study group led by AFSPC and NASA. In December 2012, after reviewing the results of these technical deliberations, NASA Administrator C. Bolden, AFSPC Commander Gen Shelton, and U.S. Strategic Command’s Gen Kehler agreed on a plan for installation of LRAs on all GPS III vehicles beginning with SV9.
Laser-Ranging Operations
GPS laser ranging will be accomplished through the International Laser Ranging Service (ILRS), and NASA will ensure all operations adhere to a set of standards and procedures. All ILRS GPS laser ranging will use 532- or 1064-nanometer wavelengths, and the reflectivity of LRAs will be optimized for these two “colors.” To support operations and accommodate this level of control and situational awareness, the ILRS has defined minimum standards for GNSS LRA cross-sections to optimize ranging to the satellites by ILRS stations.
The design of the LRA for GPS III, funded by NASA and currently being developed by the NRL, easily exceeds the ILRS recommended standards. Some satellites tracked by the ILRS are to be ranged subject to certain basic restrictions and conditions to ensure the science data gained is optimal for all stakeholders. The ILRS has developed policies and procedures for controlled tracking, and laser ranging to GPS III will be performed on a schedule issued by the ILRS Central Bureau located at the NASA Goddard Space Flight Center in Greenbelt, Maryland.
The laser-ranging schedule will be coordinated considering ground-network capabilities, GPS operational requirements, and the tracking frequency required for accurate orbit determination. Only certified/approved ILRS stations will be authorized to perform laser ranging following a predetermined assessment, using approved laser-ranging stations operating within set technical parameters (color, power, and so on). The ILRS will issue digital keys once confirmation is received that all conditions have been met, with AFSPC and NASA maintaining a role.
Summary
A positive way forward has been established to allow for the implementation of laser ranging to the GPS-III constellation beginning with SV-9 in the 2019 timeframe. The laser ranging to GPS III, followed by post-processed analysis and mitigation of systemic errors, will contribute significantly to achieving the goal of a more accurate ITRF. These applications will also be augmented by an ongoing and significant international investment in the global geodetic infrastructure of the GGOS observing networks and analysis systems. Laser ranging of GPS III will also encourage further international investments and industry innovations as higher precisions are further introduced to the world community.
Sidebar
The PNT EXCOM
The U.S. National Space Based, Positioning, Navigation, and Timing (PNT) Policy, formally unveiled in December 2004 and supported through two administrations, strengthened GPS by creating a deputy-secretary-level PNT Executive Committee (EXCOM) to coordinate federal agency oversight of this critical national asset. The PNT EXCOM is co-chaired by the Department of Defense (DoD) and Department of Transportation (DOT), with representation by the deputy secretaries, or their equivalents, from other agencies and departments. The PNT Policy maintains the U.S. Air Force (USAF) as the DoD Executive Agent for Space.
This policy also designated newer responsibilities for other agencies. The NASA administrator, in coordination with the Department of Commerce and DOT, is responsible for developing requirements for the use of GPS and its augmentations in support of civil space systems. This level of collaboration is enabled by high-level interagency stakeholder discussions on all aspects of civil GPS activities. This is vital in the age of GPS modernization among other emerging constellations, as it allows individual PNT EXCOM agencies to develop and fund new capabilities. This multi-agency collaboration is very appropriate for GPS, since PNT is a suite of services used by all federal agencies to serve the public, providing greater safety, efficiency, and economy for a multitude of governmental missions.
Collaboration through the PNT policy has allowed NASA to optimize the use of GPS-based PNT services to fulfill a variety of science missions with ever-expanding societal benefits, ranging from space operations, exploration, Earth observation, and weather forecasting, to all manner of environmental monitoring including ice-melt and sea-level fluctuations. These data are increasingly important for governments to be able to plan for and respond to changes affecting human health, economy, and security. NASA therefore continues to work closely with the USAF and other PNT EXCOM agencies to improve the performance of GPS and its products through science initiatives.
One such initiative is known as GPS Satellite Laser Ranging (SLR), and is described here, along with its implementation aboard GPS III satellites.
Acknowledgments
The authors thank these individuals for their contributions in developing a way forward for the implementation of LRAs on GPS III, clearly showing the high level of interagency interest and coordination required to make this initiative happen overly nearly a decade of work. We are especially grateful to the U.S. Department of Defense, and in particular to U.S. Air Force Space Commander General Shelton, for leadership and support in enabling NASA and our partners to realize this important contribution to GPS in years to come: Honorable Charles Bolden, Honorable Lori Garver, Gen William Shelton, Gen Robert Kehler, Letitia Long, Maj Gen Martin Whelan, Chris Scolese, Badri Younes, Michael Freilich, Jack Kaye, Barbara Adde, Norm Weinberg, Craig Dobson, Mike Moreau, David Carter, Stephen Merkowitz, Yoaz Bar-Sever, Scott Pace, Ray Yelle, Scott Wetzel, Major Janelle Koch, Col (Ret.) David Buckman, Col (Ret.) Allan Ballenger, Col (Ret.) David Madden, Col (Ret.) Bernard Gruber, Col James Puhek, Steve Malys, Thomas Johnson, Ron Beard, Linda Thomas, Mark Davis, Larry Hothem, Ken Hudnut, Hank Skalski, James Slater, Vaughn Standley, Mike Pearlman, Erricos Pavlis, Kirk Lewis, Maj Gen (Ret.) Robert Rosenberg, and the National Space-Based PNT Advisory Board co-chaired by Honorable James Schlesinger and Col (Ret.) Bradford Parkinson.
James J. Miller is deputy director of the Policy & Strategic Communications Division with the Space Communications and Navigation (SCaN) Program at NASA. He is a commercial pilot with master’s degrees in public administration from Southern Illinois University and international policy and practice from George Washington University.
John LaBrecque is lead of the Earth Surface and Interior Focus Area within NASA’s Science Mission Directorate, managing NASA’s Global Geodetic Network that provides PNT products in support of NASA’s Earth Observation program. He received his doctorate in marine geophysics from Columbia University.
A.J. Oria works for Overlook Systems Technologies, Inc., supporting NASA headquarters in the area of GPS and PNT technology. He has a Ph.D. in astronautics and space engineering from Cranfield University, UK.
