Tag: Javad Ashjaee

  • J-Shield from JAVAD to Counter Interference

     

    JAVAD GNSS announces that it has improved its GNSS protection filters, not only to protect the L1 band against all interferences (including LightSquared 10L, 10H and 10R handset), but to protect against all other interferences which may come in any other GNSS band.

    The company calls its improved filter the J-Shield, and states that it will “help make the bands near any GNSS band free for other usages like broadband wireless, which the United States desperately needs to catch up with other nations, as currently the United States is number 16 in the world [in broadband capacity], and to help to create competition to potentially reduce U.S. wireless broadband costs to 1/3 of what they are today.”

    CEO and founder Javad Ashjaee will present details on the J-Shield on Thursday, September 20, at the ION-GNSS conference in Nashville, Tennessee, in a talk titled “All about GNSS Interferences and Jammers.”

    The talk will cover:

    1. Where does interference come from?
    2. How to know, view, quantify and analyze interference.
    3. How to protect against interferences.
    4. Implementation of these features in JAVAD GNSS’s mass-produced commercial products.
    5. Introduction of the J-Shied for all GNSS bands.

    The company will also have an exhibit on the ION-GNSS show floor in the Nashville Convention Center, from Wednesday, September 19 to Friday, September 21.

  • Letter to the Editor: Automatic Gain Control, Spoofing

    Cover: GPS WorldJust for the record: what is reported in “Detecting False Signals With Automatic Gain Control” (April GPS World) is what we introduced a long time ago and is reflected in one of our videos, and implemented in all of our GNSS receivers. AGC information is one of the four ways, and the least significant way, that we show interferences. There is a big difference between showing something in the laboratory and in some receivers, compared with having technology in mass production that everyone can understand and use.
    — Javad Ashjaee
    JAVAD GNSS, San Jose, California

    Author Dennis Akos replies:
    I am sure JAVAD receivers work quite well to leverage AGC to flag RFI (it was not the survey-grade model I used for the paper, though). The original Nordnav R30 GPS receiver showed both AGC and the L1 frequency spectrum back in 2004. u-blox has an RFI flag in its receiver, which is based on AGC. Others likely do as well.

    In any event, AGC detection of RFI (and you could say spoofing) is not new. I coauthored an ION GPS paper with Bastide and others back in 2003 showing how powerful AGC could be to detect interference. In 1997 Per Enge had a student, Awele Ndili, working with the Plessey chipset, who did something similar, checking the AGC for signs of RFI.

    So when all the hubbub came up about spoofers a couple years back, I tried to flag the question — why be concerned about this? AGC can tell when more power is coming in the frequency band and thus flag RFI or spoofing is happening. So spoofing is no more of a threat than simple jamming, should one be concerned about it and make a relatively small effort to check for it.

    I was quite impressed with the spoofer design Humphreys/Psiaki/Ledvina came up with (“Straight Talk on Anti-Spoofing,” January 2011, and “Assessing the Spoofing Threat,” January 2009). Quite neat, needs very little additional energy with the lift and carry-off approach. But also very hard to leverage for any dynamic case where the victim receiver did not want to be spoofed (spoofing a dynamic receiver with the approach? Doable, but really hard, and would still inject more RF energy). So it left the threat, in my mind, to those who are being monitored and want to spoof their device: very small subset — the fisherman in illegal waters, the prisoner with ankle monitoring. This is the hardest detection case, but I am still fairly confident AGC can work here.

    Main motivation for the article: I was troubled that I did not see the need for folks to be up in arms any more about spoofing than plain old jamming.

    Again, my premise: in the great majority of cases spoofing is easily detected using technology already in a majority of receivers, making it no worse than jamming, and the harder cases should still be detectable with additional effort/sensors. But it is important for all to remain vigilant, as these AGC-based techniques do need to be implemented/leveraged to avert the spoofing threat — and Humphreys/Psiaki/Ledvina deserve credit for bringing this potential to light. Even with successful spoofing detection it will appear as much less sophisticated jamming, not allowing the receiver to obtain position/time information.

    So that is why I worked with the Swedes to try and show this and get that message out. It would have been great to test with one of the more sophisticated jammers (perhaps will have a chance to do so with an upcoming test), but I did not have one, so we just did simple repeater jamming.

    I am glad Javad is preaching the same message. It would be great to see him to more widely disseminate that message and put much of these concerns to rest.

    Regarding the video: Thanks, Javad. Really some nice features. I need to get a TRIUMPH-VS or two here at Colorado University to work with. Quite curious as to the sensitivity of the AGC. But the receiver has a great feature set!

    One quick comment. In the video where you tested the RX with the jammer — I might go back and qualify that indicated you did the test under controlled/allowed conditions. I recall we published an GPS RFI test back about 10 years ago, and we had some official inquires for more details on the testing and why we were broadcasting in the GPS band. No idea how/where you did your testing (assuming 746th Jamfest or similar), but unless you state otherwise, it might bring some unwelcome attention.

  • Engineers Invited to Explore GNSS Filters at JAVAD GNSS

    Javad Ashjaee, president and CEO of JAVAD GNSS, invites engineers “who want to roll up their sleeves” to a working session at his company’s San Jose, California facility on Tuesday, January 17, to “find solutions and discuss technical details” related to the LightSquared/GPS conflict. The invitation comes at the end of a lengthy statement, “A Technical Story of a Bad Filter and a Good Filter — Which Turned Political!,” downloadable as a PDF from the company’s website.

    A few excerpts from the paper, which will also appear as an advertisement in the January issue of GPS World magazine, follow. The GPS World webinar that is mentioned in the paper is also downloadable as an audio file with presentation slides, a 50-minute talk given by Javad Ashjaee on December 8: A Proposed Solution for LightSquared Effects on High-Precision GPS.

    From the recently released paper:

    “I have been reflecting on events related to the GPS interference issue and LightSquared. What I discovered revealed the root of this problem, and as I will describe in this paper, it is entirely caused by poor design of GPS receivers The problem can be solved easily and with existing technology. In fact, it already has been solved.

    [ . . . . ] “In order to defend the GPS system and provide technical data, I started my own investigation of the problem. I soon realized that my own company had a fundamental problem in the first stage of our antenna system. It was allowing other radio energies into the receiver in addition to the Global Navigation Satellite System (GNSS) signals. I recognized that the flaw in our filter system would degrade the performance of our GNSS receivers whether LightSquared’s system is deployed or not.

    “As an engineer, I always strive to innovate my products and took it upon myself to see if we could develop a device that filters out as much noise as possible from the adjacent band without affecting the integrity of the GNSS signals. Unfortunately, this was never a priority in our industry – we always used filters that offered little protection against interference. I soon drew the conclusion that the standard operating procedure resulted in degraded performance.

    [ . . . . ] “Our challenge is to build the best filter that keeps the GNSS signals intact and blocks unwanted signals as much as possible. In other words, make the side slopes, or skirts, of a filter as steep as possible. How difficult it is to build such a filter? How much would it cost?

    [ . . . . ] “If we build better filters and better GNSS receivers, both general purpose users and high-precision users of GNSS will get improved results. In addition, the Figure 5 [all figures are shown in the downloadable PDF at JAVAD GNSS website] filter will protect the receiver from hearing LightSquared signals. This is shown in Figure 7, below. The GPS and GLONASS signals are shown in green. Our new steep-skirt filter is shown in grey, and the LightSquared signals are pink. Note that this new filter completely blocks out the LightSquared signals without reducing the signal strength of GNSS signals.”

    [ . . . . ] “The reaction from many of my industry peers to my scientific analysis was decidedly unscientific. My pure technical findings were tagged as hostile, harsh, disrespectful, political, self-serving and betraying. I ask my critics: How in the world could I possibly want to cause harm to GNSS systems that I have worked so hard in the past 30 years to improve?
    If GNSS system receives any harm, my company and I are among the first to feel the damage!

    “I’m not a stranger to controversy, so I chose to ignore them. I received similar personal attacks for ten years when I was working on GLONASS. Déjà vu!

    [ . . . . ] “This technical matter has a lot of lawyers, lobbyists and spin doctors involved, but it’s the engineers who have the ability to solve this problem.

    No matter what happens to LightSquared, I am determined to build a better filter system for our GNSS receivers and offer better products to surveyors worldwide, and if we can accomplish this while facilitating a better RTK network, all the more reason.

    I would like to invite engineers who want to roll up their sleeves and find solutions and discuss technical details to join me and several of my peers on Tuesday, January 17, 2012 in my San Jose facility. Please RSVP to javad at javad dot com.”

  • The System: Technical Report on LS/GPS Interference

    Once again, developments in the news outpaced print technology’s ability to keep up in the LightSquared saga. Shortly after the July issue went to press on June 27, the TWG final report appeared on June 30. Thus you readers, who received the magazine circa July 15, held old news in your hands. Likely this will occur again.

    Chronologically in this section, from late June to mid-late July:


    Final Report of Technical Group

    The final report to the Federal Communications Commission (FCC) by the technical working group (TWG) tasked to analyze effects of powerful terrestrial L-band transmitters on the GPS signal and services finally appeared on June 30, nearly two weeks after its assigned date. LightSquared had requested an extension and used the time to write many pages of self-justification and legal argument of the company’s case. But the facts are clear: the LightSquared signal would devastate services for users of all GPS receivers tested.

    “Based on the analysis performed, LightSquared should not be permitted to use the L-Band spectrum for a densely-deployed, non-integrated terrestrial-only network. Such a network would cause unacceptable interference to GPS operations, wiping out an installed base of over 500 million units used in a wide array of public safety, aviation, industrial, and consumer applications. While mitigation techniques utilizing filters were discussed in theory, they could not be tested as part of the WG effort because filters do not exist, even in prototypes. No information considered by the WG demonstrated that any mitigation techniques — other than relocation of the proposed terrestrial network to an alternative band — would be successful.” (From the U.S. GPS Industry Council’s overview)

    The final report is not easy to find on the FCC’s labyrinthine website. Download it here.

    LightSquared COO, President Gone

    Harbinger Capital Partners, the hedge-fund firm that owns LightSquared, announced on July 6 that its chief operating officer had resigned by “mutual agreement.” Peter Jenson’s exact role in the application for a FCC conditional waiver is unknown at this time; however, it is certain to have been key.

    On June 30, the date of the TWG report, Harbinger Group Inc., a publicly traded company majority-owned by Harbinger Capital, appointed Omar Asali as acting president, replacing Harbinger founder Phil Falcone, who continues as chairman and chief executive.

    DoD, DoT Say Hands Off L-Band

    The U.S. Departments of Defense and Transportation declared their strong opposition to the LightSquared plan in a June 14 letter to the National Telecommunications and Information Administration (NTIA).

    In their official statement, “The Departments continue to support the National Broadband Plan, but cannot do so at the expense of a global, ubiquitous utility such as the Global Positioning System. The Departments encourage further assessment of any alternative spectrum and/or signal configuration plans.” See www.pnt.gov.

    The Department of Homeland Security was conspicuously absent from the signatory line, as it has been in most public goings-on. Under pointed congressional questioning about its reluctance to enter the ring, a DHS spokesperson averred that the agency had been “carrying a lot of water.”

    Javad Says End P-Code Encryption

    To solve the LightSquared versus GPS controversy, Javad Ashjaee, president and CEO of JAVAD GNSS, has appealed directly to President Obama to discontinue the encryption of P-code, the restricted military GPS signal. “This policy is not helping national security. It is hurting both precision users and the broadband project. We need more broadband, for global, fast, and inexpensive real-time kinematic (RTK) GPS.”

    IIF II Up, Up, and Away

    The U.S. Air Force successfully launched GPS IIF-2 Space Vehicle Number (SVN) 63 aboard a United Launch Alliance Delta IV Medium rocket on July 16 from Cape Canaveral Air Force Station, Florida. This is the second in the series of 12 GPS IIF satellites that Boeing has on contract with the Air Force. Boeing reported the first satellite signals from space received within four hours. On July 20, stations of the International GNSS Service tracking network reported a signal from SVN63’s L-band transmitter. Testing will ensure health of L1, L2, and L5 signals beforethe satellite is turned operational; this is expected in August.

    The satellite joins the GPS constellation of 30 operational satellites. SVN-63 will assume plane D, slot 2A, replacing SVN-24 after nearly 20 years of service.

    The IIF satellites will provide greater navigation accuracy to users through improvements in atomic clock technology and a more robust signal for commercial aviation and safety-of-life applications, through the third civil signal (L5). GPS IIFs will have a longer design life of 12 years, and will continue to deploy the modernized capabilities that began with the modernized GPS IIR satellites, including a more robust military signal.

    A Boeing statement concluded: “With safety checks completed, checkout will begin under the direction of the Air Force GPS Directorate. Checkout includes payload and system checks to verify operability with the GPS constellation of satellites, ground receivers, and the Operational Control Segment system. Boeing will officially turn over SVN-63 to the Air Force 50th Space Wing and the 2nd Space Operations Squadron this fall after the spacecraft completes on-orbit checkout.”

    GPS III Design Review Completed

    Lockheed Martin successfully completed on schedule a system design review (SDR) for the GPS IIIB satellite increment under the U.S. Air Force’s next-generation GPS III program. The company is under contract to produce the first two of a planned eight GPS IIIA satellites, with first launch projected for 2014. The contract, which features a “back to basics” acquis
    ition approach, includes a Capability Insertion Program (CIP) designed to mature technologies and perform rigorous systems engineering for future GPS III increments.

    The GPS IIIB SDR established requirements for the capability insertion planned for the follow-on GPS IIIB satellites and “validated the satellite design will meet the ever-increasing demand of more than one billion GPS users worldwide.”

    GPS IIIA will deliver signals three times more accurate than current GPS spacecraft and provide three times more power for military users, while also enhancing the spacecraft’s design life and adding a new civil signal designed to be interoperable with international global navigation satellite systems.

    GPS IIIB will provide higher power modernized signals, a fully digital navigation payload capable of generating new navigation signals after launch and a Distress Alerting Satellite System payload that relays distress signals from emergency beacons back to search and rescue operations.

    Galileo Finds LS Interference

    The head of the European agency overseeing Galileo filed an official FCC comment, expressing strong concern about the Lightsquared terrestrial signal. Analysis in Europe shows that LightSquared transmissions “have considerable potential to cause harmful interference to Galileo receivers.”

    Video. Meanwhile, the European Space Agency has a video of Galileo in-orbit validation satellite assembly and testing. The first two satellites are destined to launch together at the end of October aboard a Russian Soyuz rocket, from the European spaceport in French Guiana. They will join two experimental satellites already on orbit. See video.

  • To Solve LightSquared Issue, Javad Ashjaee Calls for End to P-Code Encryption

    To solve the LightSquared versus GPS controversy, Javad Ashjaee, president and CEO of JAVAD GNSS, has appealed directly to President Obama to discontinue the encryption of P-code, the restricted military GPS signal. His comments came in the context of the LightSquared/GPS interference imbroglio, as part of his solution to the conflict over spectrum. “This policy is not helping national security. It is hurting both precision users and the broadband project. We need more broadband, for global, fast, and inexpensive real-time kinematic (RTK) GPS.”

    Ashjaee, a longtime leader in high-precision GNSS equipment, made the remarks during a panel discussion at the Esri Survey Summit, and expands upon them in a video posted on his company’s website: “A Solution for LightSquared.” In the video, he calls the LightSquared saga “a good thing, because it brings the issue of in-band interference to many GPS users, especially surveyors and high-precision users.”

    He goes on to address three issues: collateral damage, why high-precision receivers are more affected by the LightSquared attack, and finally a proposed solution to the problem.

    In the first section, he disputes the assertion that LightSquared interference to 5 percent (surveyors) and 1 percent (military) of GPS users should be tolerated as collateral damage. “When you add substance to the numbers, you see how quickly this argument fails. The military is the backbone of our national security, and high-precision users are the backbone of our financial security and growth.”

    On the second topic, he gives two reasons why high-precision receivers are more affected by the LightSquared signal, briefly summarized here as:

    • the crucial importance of the arrival time of the signal edges; the edges are first to be distorted by interference. Narrow filters, proposed as a solution by LightSquared, also blur the signal-edge shape.
    • the encryption of P-code on L1 and L2 bands, degrading their effectiveness by a factor of 1,000, according to Ashjaee. “Encryption does not do any good to anybody.”

    As his solution to the problem, Ashjaee says Lightsquared should stay further away from the GPS signal, and use a cascade of filters; secondly, he calls on President Obama to discontinue P-code encryption, at least until the new L2 signal is operable in 8 or 10 years. “This would make GPS less vulnerable to the LightSquared project and others like it.”

    In a subsequent conversation with GPS World, Ashjaee likened the P-code situation to that of selective availability (SA), another U.S. government effort to restrict use of high precision. Ashjaee recalled campaigning vigorously against SA in 1991, with full-page ads in GPS World depicting the Mona Lisa painting with many missing parts. “Selective availability is a step backward in providing the best of this excellent work [GPS] of science and art. As the leader in GPS technology, we consider selective availability as being neither good science nor good politics,” the ad copy reads.

    Ashjaee adds with a twinkle, “[A former director of the GPS Wing] told me that a high general in the Air Force had that ad pinned to the wall behind his desk. Why? Who knows. Perhaps he agreed with it.”

    SA was discontinued in May 2000.

    (As an interesting historical side-note, in an adjacent ad in the same January 1991 issue, the company advertised “Ashtech’s True P-Code Advantage.” At that time, P-code was not encrypted. The copy reads:

    “GPS was designed as a dual-frequency system and the Ashtech P-12 GPS receiver enables users to take full advantage of GPS capabilities. Dual-frequency reception eliminates ionospheric refraction effects, so medium-to-longer baselines can be measured more accurately.

    “High-quality P-code measurements on both bands also enable shroter station occupation time, further increasing productivity for survey crews.”

    “P-code correlation produces carrier-phase measurements of higher accuracy because of significantly higher SNR over conventional codeless techniques. This, combined with the P-12 receiver’s ability to measure full-wavelength L2 carier-phase, allows nearly instantaneous integer cycle-phase ambiguity resolution for kinematic survey, precision navigation, and other applications.

    “Unlinke conventional codeless techniques, ‘true P-code’ tracking provides inherent immunity from jamming for uninterrupted tracking in areas of high interference.”)

    “The U.S. policy of national security and P-code is 30 years old,” Ashjaee resumes. “This policy was devised at the time we were head-to-head in the Cold War with Soviet Union. They had missiles targeted at us, we had missiles targeted at them. That’s why we encrypted the P-code. But this situation is gone. There is now an agreement between Obama and [Russian president] Medvedev that citizens of the two countries can have 3-year visas to visit each other. Our missiles are not targeted at each other.”

    “Since the inception of GPS, there is no shred of evidence that GPS has ever been used to attack any U.S. national security, let alone its P-code signals.”

    Further, Ashjaee pointed out, “At that time, GLONASS did not exist, and we did not want them to use our system. Now GLONASS exists, and its signal is arguably more robust than GPS.”

    Ashjaee called on President Obama to turn off P-code encryption. “This policy is not helping national security. It is hurting both precision users and the LightSquared project, which we all desperately need. We need more broadband. They know the system is not good, and they want to put another clear code [on L2]. It will take 8 or 10 years. Turn off encryption temporarily until we have it. Encryption can be turned on in a fraction of a second whenever needed.”

    “Turning off P-code encryption not only makes the GPS signalmore robust to LightSquared, but also protects it against all kind of other interferences, including harmonics of innocent signals like harmonics or radio stations.”

    He embraced the use of wideband communication between base and rovers for RTK GPS. “We have base and rovers, with VRS networks. The corrections must be transmitted from base to rovers. Now we have a mess of communications: UHF (different in every country, difficult to certify in every country), spread-spectrum, VHF, Ethernet, WiFi. These are kludgey communications. If we have broadband, similar to Lightsquared, we have RTK globally, fast, and inexpensive.”

    In a separate conversation with GPS World, another expert in high-precision use confirmed that “we have worked very hard in the past, when bandwidth was much more expensive, to minimize the bandwidth required to send differential GPS corrections with minimal latency. Sensor fusion has mitigated the latency issue as well. As robotics applications increase, not only base-rover communications but tons of data relevant to precise positioning, sensor fusion, including vision, RF ranging, path planning, mission planning, obstacle detection, and so on, will be needed. Industrial, scientific, and medical (ISM) band spread-spectrum and ultra-wideband (UWB) ranging systems have a lot of problems that 4G systems could alleviate.”

    “We need a coalition to save GPS and Lightsquared,” concluded Ashjaee. “It’s a nice complement.”

    “Broadband would be a good help to our industry, and to our technology. We want global, universal wideband communication, either through towers or satellites, or through any means to transmit base station or VRS network corrections to rovers.”

    Ashjaee offered to debate the P-code encryption issue with representatives from the GPS Wing, State Department, Department of Defense, PNT ExCom, and others, at the annual GPS World Leadership Dinner, held during the ION-GNSS conference each September. “It will be a very lively debate,” he said. “Add Tom Stansell, too. And representative of LightSquared.”

     

  • How GPS and GLONASS got together — and other recent events

    The recent broadcast of the first CDMA signal from the new GLONASS-K satellite culminates a long series of events that began in 1989. A key participant gives a first-hand account of the history of many meetings, formal and informal, that created true interoperability between the two major satellite systems, giving users a modern GNSS in action.

    October 18, 1989, the Queen Elizabeth Auditorium in London, around 8:30 am. Unknown to me, two 60-minute periods were about to imprint themselves indelibly on my memory.

    I walked up the stairs to the exhibition booth of my company, Ashtech, at The Royal Institute of Navigation conference. My good friend, the late Ann Beatty, met me and asked, “Any news from home?”

    I thought it was just a casual customary question, and replied: “Thanks, all OK.” She had a strange look on her face. She continued: “Are all your family really OK?” I replied again: “Thanks, all good.” She then realized that I had no clue about the cataclysmic event that had hit the San Francisco Bay area. She abruptly said, “Don’t you know? The big one came! The big earthquake hit San Francisco!”

    Californians know the rumors that when The Big One comes, Nevada will have ocean frontage. Now she was telling me that The Big One came! I rushed to the phone, and the recorded AT&T message said, “All lines to your area are out of service.” It took me another hour to find out that this was not yet The Big One, and that my family was safe. I will never forget these 60 minutes of my life. Never!

    Nor will I ever forget the events of the next 60 minutes.

    After the stress had settled a bit, a delegation from the Russian Space Agency visited our booth. First they expressed their sympathy regarding the earthquake. Then we discussed GPS technology and its similarities with GLONASS. Both systems were fairly new then, although GPS had started first, with a Block I launch in 1978, followed by GLONASS with a launch in 1982. At the time we met in London, GPS was flying 12 satellites, and GLONASS also had 12 in orbit.

    The Russian delegation visited all GPS manufacturers’ booths in the exhibition hall and then gathered in the coffee area for their private discussions. A few hours before the conference closed, they returned to our booth and said, “We want to combine GPS and GLONASS, and you are our first choice.” Simply put, I was fascinated and excited.

    After working out visa and travel details, four months later I arrived in Moscow in the cold days of February 1990. It was still the Soviet Union.

    I had grown up in Iran where the U.S.S.R. was our neighbor to the north. Remembering the global political landscape of my childhood days, I felt both fascination and fear as my airplane landed at Moscow airport.

    Upon meeting the people who greeted me at the airport, my fears disappeared, and my fascination grew stronger.

    Our first formal meeting took place in the Institute of Space Device Engineering (ISDE), a division of the Russian Space Agency that was responsible for the GLONASS program. The opening photo shows me with the late Dr. Nikolay Yemelianovich Ivanov, director of the GLONASS program, at that first meeting.

    I want to focus a bit on the GLONASS team and applaud them for their efforts. What makes the GLONASS team special is that they worked under much harder political and financial conditions than the GPS or Galileo teams. But still they were able to make the project successful. The Soviet Union and later Russia went through huge political, economic, social, and geographical revolutions, but the GLONASS team managed to keep the satellite navigation program alive and successful.

    Galileo’s management, while enjoying much more stability and financial luxury, can certainly appreciate and understand the significance of what the GLONASS team accomplished. Galileo also benefitted from the European integration of 27 countries, while the Soviet Union disintegrated into 15 separate nations.

    Despite all their heroic work, individuals on the GLONASS team have received almost no international recognition. At home they went unnoticed, due to their political situations. For example, the highest international recognition that Dr. Ivanov received was that he became a member of the GPS World Advisory Board, which I facilitated. In this article, I want to salute some members that I know and at least keep their names and photos recorded in the GPS World archives.

    In the first meeting, everyone recognized and emphasized the great potential of combining GPS and GLONASS for a variety of applications. I became more assured of the deep desires of my hosts to make this happen. They had prepared detailed charts and plans, especially for high-precision applications. They also gave me the GLONASS Interface Control Document (ICD) for the first time.

    We signed a cooperation protocol and agreed to explore technical details in our next meeting, which occurred a few months later. There I began to know Dr. Stanislav “Stas” Ulianovich Sila-Navitsky, at that time the chief scientist of Dr. Ivanov’s team. Later he became my vice president in three companies that I founded. He also became my best friend of 19 years, before he passed away on May 7, 2010.

    We had several meetings in Moscow and one in Paris in the headquarters of our partner SAGEM.

    I have wonderful memories of all the meetings. One meeting in Paris included General Leonid Ivanovich Gusev, the head of ISDE. One evening Stas called my hotel room and asked me to cancel our dinner at a famous French restaurant and instead join them for a “real dinner.” Apparently General Gusev was tired of French food! The real dinner took place in the General’s hotel room, and the menu consisted of dark Russian bread, Russian kielbasa sausage, Russian seledka herring, and an abundance of Russian vodka.

    Our first announcement of combining GPS and GLONASS was published in GPS World magazine, in only its second issue, March/April 1990. That year we had a poster banner in our Institute of Navigation exhibition, showing the American flag and the Soviet flag (hammer and sickle) next to each other. My very good friend, Colonel Gaylord Green, the second director of the GPS Joint Program Office, refused to have his picture taken with me in front of that banner. Instead, we stood over to another side of the booth for his photo.

    A few months after the Paris meeting, the political process known as perestroika began and caused the Soviet Union to end. Life became extremely difficult for Russians.

    I called Stas to discuss the situation. We concluded that we had no choice but to continue the plan on our own if we wanted to combine GPS and GLONASS. I went back to Moscow several times, and in February 1992 officially opened the Moscow office of Ashtech. This office is still operational in Moscow with about 10 percent of the original team. It is now in the process of being purchased by Trimble Navigation. What a turn of events!

    In 1996 we introduced the first combined GPS and GLONASS receiver; the product announcement appeared in GPS World, July 1996

    Back home in the United States, the situation was different. Supporting GLONASS was an unpatriotic act. The most prominent figures of GPS teased me for wasting my time with GLONASS. The news favored their arguments: the Russian economy was going downhill. In September 1998, the Russian ruble collapsed more than 300 percent within a week. Banks closed. Even Coca Cola was not able to pay its employees in Russia because of bank closures. Many western companies left Russia. During that period, I intentionally stayed longer times in Moscow and managed to pay our employees without a day of delay. Furthermore, a more than three-fold rate change in favor of the dollar made our employees relatively rich, because their salaries were based on the U.S. dollar.

    I remained confident that GLONASS would succeed because I had seen the enthusiasm and dedication of GLONASS management and engineers.

    My Ashtech partners wanted to take the company public to recoup their investments. They thought Wall Street would negatively view GLONASS and the Russian connection. So my aspiration did not match theirs, and I started Javad Positioning System (JPS) in 1996. About 90 percent of the staff engineers followed me to JPS.

    One of John Scully’s vice presidents did to Ashtech what Scully did to Apple. Meanwhile JPS became very successful, as Apple did when Steve Jobs returned.

    Subsequent to another event and termination of some obligations and commitments, I started JAVAD GNSS in June 2007. Almost all of the key people followed me again. Our current team has a history of working together for close to 20 years.

    In JAVAD GNSS we raised the bar of GPS/GLONASS integration to a higher level and focused in two new directions. The first was to eliminate the problem of GLONASS inter-channel biases, which is inherent to the GLONASS frequency-division multiple access (FDMA) signal structure. The second was to support the opinion of GLONASS engineers who were pushing for a new code-division multiple access (CDMA) signal for GLONASS, similar to the GPS signal.

    We resolved the GLONASS inter-channel biases issue around 2009 and announced, “Our GLONASS is as good as GPS.”

    On the second front, we worked with the top managements of ISDE and the Information Analysis Center (IAC) of the Russian Space Center to demonstrate the advantages of CDMA for high-precision applications.

    Some years ago, Stas had confided in me that the issue of CDMA was nothing new, and had been extensively deliberated at all levels of various GLONASS organizations during the early design phase of the system. The result of all these discussions was that engineers and technical people favored CDMA, but the higher management, mostly influenced by the military organizations, held out for FDMA. The reason for favoring FDMA is still a secret, though some believe that they just wanted to be different from GPS and did not see much advantage in CDMA. Some also believed FDMA gave better jamming protection.

    Of course in those very early days, no one imagined using GPS or GLONASS for high-precision applications, and as such truly there was not much difference between CDMA and FDMA. Much later, the notion of using carrier phase of GPS and GLONASS signals for high-precision applications was discovered, and then the advantages of CDMA became relevant, as Dr. Ivanov also hinted in our first meeting.

    After we combined GPS and GLONASS, and as a lot of our worldwide users began comparing the two systems, the issue of CDMA versus FDMA again came up for discussion among the GLONASS authorities.

    More recently, since 2007, we had several meetings in the offices of ISDE in Moscow, in IAC in Korolev (the Russian Space City), and several in our JAVAD GNSS office in Moscow. Most importantly, we had several meetings in my Moscow apartment, enhanced by Russian vodka and the best Armenian cognac, courtesy of Sergey Revnivykh, head of IAC. All meetings were open and candid, discussing and demonstrating the advantages of CDMA, in support of the ISDE engineers who were reluctant to express their opinion above certain levels.

    I also met with the head of the Russian Space Agency, Dr. Anatoly Nikolayevich Perminov, who personally supported and sponsored me in obtaining an extended Russian residency visa. Let me also express my appreciation for receiving the Medal of Honor from the Russian Cosmonauts Federation, along with the official astronaut watch. I don’t understand the reason for receiving a Kalashnikov AK-47 semi-automatic rifle from ISDE for my birthday. I wonder how I can transport it home!

    General Anatoly Shilov (deputy director of the Russian Space Center), Dr. Vicheslav Dvorkin (GLONASS deputy general designer), Sergey Revnivykh, Viktor Kosenko (first deputy of chief GLONASS designer) and Sergey Karutin (GLONASS senior scientist) are the new generation of GLONASS leaders who deserve credit for supporting CDMA on GLONASS. Recently, a new GLONASS-K sat-ellite was launched, transmitting an experimental CDMA signal in addition to the legacy signals. Almost immediately, we announced tracking of the new GLONASS-K satellite and its new L3 signal details, hours after it started transmitting. See GPS World archives and our website for details of this signal which seems, in all aspects, as good as GPS.

    Another new issue of significant international concern was a new frequency for GLONASS. This issue was more political than technical, and is discussed under the umbrella of interoperability.

    In the early days of my frequent travels to Russia, the KGB probably suspected that I was a CIA agent — and the CIA probably suspected that I was a KGB agent! I would not be surprised if both the CIA and KGB monitored every bit of my travels and activities. After some years, the San Francisco airport authorities stopped interrogating me for my activities in Russia any time I came back home. Perhaps because of their deep investigations, I earned the trust and friendship of both sides, and their confidence that I had nothing in mind other than helping to integrate GPS and GLONASS. I was an unofficial member and friend of both U.S. and Russian delegations during the so-called interoperability discussions since 2007, which sometimes touched on the CDMA issue as well.

    Some of the most fruitful and friendly discussions between the U.S. and Russian delegations occurred in my apartment in Moscow, after their official meetings. Ken Hodgkins of U.S. State Department; Mike Shaw, director of the National Space-Based Positioning, Navigation, and Timing Coordination Office; David Turner, director of the Center for Space Policy & Strategy; Scott Feairheller of the U.S. Air Force; and Tom Stansell, consultant to the GPS Wing were some of my honored guests.

    The new GLONASS frequency discussions are still in progress, and I am proud to host and support both sides the best that I can. Sometimes it is fun to observe that discussions resemble poker games where hands are known to all sides, but players still try to bluff each other! Let’s leave it at that for now.

    In May of this year, I had a conversation with General Anatoly Shilov, now second-in-command of the Russian Space Agency, reporting to the first deputy of the minister of defense, General Vladimir Popovkin, who recently replaced Dr. Perminov as head of the Russian Space Center. This is an indication of increased attention and support from the Russian government to its GLONASS program. In our conversation, General Shilov was enthusiastic and optimistic that the GLONASS program will move forward faster.

    GLONASS has proven to be a real and reliable complement to GPS. If it were not for the failure of the launch of three GLONASS satellites in December 2010, its constellation would be complete and fully, globally operational today. It will happen soon. Sergey Revnivykh estimates that currently the system has 99.8 percent global coverage.

    Today, a truly reliable and fast RTK is not possible without combining GPS and GLONASS satellites.

    The most recent testimony to the success of GLONASS comes from the long-time GLONASS opponents who once criticized me for supporting the system. Recently they had to pay a lot of money to acquire the first company that I founded in Moscow, which they believed would never survive.

    This year at JAVAD GNSS, I and most of my original employees and GLONASS designers are celebrating our 20th year in Russia, and we are working harder to make the integration of GPS and GLONASS even better.

    On May 7, 2010, Stas lost to leukemia. He was not present to witness the successful introduction of our TRIUMPH-VS receivers. My refrigerators in Moscow are full of medicines that he brought for me any time I had a little cold. I miss him a lot, and our team is dedicated to following the path that Stas loved so much.

    I want to briefly summarize the current status and the future of GPS and GLONASS from the users’ point of view.

    GLONASS now has 24 satellites transmitting FDMA signals in two frequency bands. The failure in the last launch to deploy three more satellites delayed completion of the constellation to the end of 2011. The good thing about GLONASS is that both of its L1 and L2 signals are not encrypted and give better data than GPS P1 and P2 that are encrypted.

    GLONASS is considering a plan to add CDMA signals to all satellites and not suffer from inter-channel biases. But it will take about 10 years for this plan to become complete for public use, even if the plan is approved and followed. At JAVAD GNSS, we have already mitigated the effect of GLONASS inter-channel biases to the accuracy of better than 0.2 millimeters. We made GLONASS FDMA the same as GPS CDMA by adding some innovations (patent pending) and enhanced algorithms.

    The GPS plan is to add a third frequency signal (called L5) and add an unencrypted signal in L2. But it will take several years to have enough new satellites transmitting these new signals to make them usable for daily work.

    In the near term, we have two complete systems, consisting of about 30 GPS and 27 GLONASS satellites. The current non-encrypted GLONASS signals give it an edge over the current GPS encrypted signals, given the fact that we have mitigated the GLONASS FDMA inter-channel biases.

    GLONASS is also enhancing its control segment to better monitor GLONASS satellites and improve the system’s clock and orbit parameters. Most of these errors are cancelled in differential and high-precision applications anyway.

    Existence of two complete and free systems, GPS and GLONASS, will place some doubt on the future of Galileo, as it will be extremely difficult for Galileo to hope to collect money from users to fund itself. The addition of Galileo, as a third system, will not really add much benefit for users anyway. The only push for deploying Galileo must come from some European military organizations to support their specific interest.

    I have been extremely fortunate also to have had the opportunity to work on GPS from its early days, co-pioneering high-precision applications at Trimble Navigation. I owe a lot to Charlie Trimble, who helped me to lift myself up when I sought refuge in the United States in 1981. He taught me GPS as well as dedication in business. I also benefitted from Sunday meetings with Dr. Bradford Parkinson, the first program director of GPS, who was and still is a board member of Trimble Navigation. I am curious to find out how Brad, as a board member, voted in the recent matter of the purchase of Ashtech. Since leaving Trimble, my innovative products at Ashtech, JPS, and JAVAD GNSS have been well documented through the years in GPS World.

    My emphasis on GLONASS in this memoir is only to record some histories and recognize GLONASS and some of its pioneers who were often overlooked. GPS is already a well-known, well-established system and is the backbone of GNSS.

    As a final note, let me add that our current JAVAD GNSS products have the option of tracking all current and future signals of GPS, GLONASS, QZSS, and Galileo. Yes, Galileo too!

  • Galileo, GLONASS, and GPS

    By Javad Ashjaee, President & CEO, Javad Navigation Systems

    The launch of the Galileo test satellite marks another very significant and exciting day in the history of navigation. Just as competition between GPS manufacturers rapidly enhanced technology and performance, the competition between the constellation providers should do the same.

    In 1984 a high-end GPS receiver weighed more than 100 pounds, performed poorly, was very difficult to operate, and came with a price tag of about $200,000. Thanks to competition, a high-end GPS receiver now weighs less than one pound, performs significantly better and with greater ease, and costs less than $5,000.

    The benefits of the competition Galileo will bring are already apparent. I believe that the Galileo project had a significant role in removing Selective Availability (SA) from the GPS signal, or at least expedited it. In fact, the removal of SA was announced at the first conference discussing Galileo. The Galileo project also proved to be a positive influence on the GPS modernization project and encouraged faster development of GLONASS satellites.

    Undoubtedly, competing with GPS was the main reason and force behind the creation of GLONASS. GLONASS, in turn, helped the removal of SA from GPS and encouraged the Galileo project. With Galileo, history may very well repeat itself.

    Galileo Advantages. Galileo has several advantages over its historical counterparts. Galileo benefits from more than 30 years of experience with GPS and 20 years with GLONASS. It should be, and most probably will be, more advanced than GPS and GLONASS from the get go. Galileo also has the luxury of international support in general and that of U.S. GPS officials in particular. In contrast, GLONASS was a project of the Cold War and was, at best, ignored by the West. I witnessed current U.S. support for GLONASS, however, a few months ago when coordinating the meeting between U.S. Department of Defense and Russian officials to discuss common GPS and GLONASS signals. With a solid support system and history on its side, Galileo has a promising future.

    That is not to say that Galileo goes unchallenged. GPS and GLONASS started mostly as military projects. The two recent wars clearly demonstrated the significance of such navigation systems as an essential military component, forcing military powerhouses to compete further and faster. Galileo’ motivation, however, is partly military, partly commercial, and partly pride. Satisfying the commercial motivation is a factor that, in my opinion, could hinder the timely progress and success of Galileo. The one-country support of GPS and GLONASS seems to have expedited the decision-making process. Galileo has scattered decision-making centers but seems to be resolving this disadvantage quickly.

    Galileo Opportunities. From the technical side, I do not see any fundamental problem for the interoperability of GPS, GLONASS, and Galileo. GPS and GLONASS signal structure differences are much more drastic than those of GPS and Galileo. Yet we were able to circumvent GPS-GLONASS technical issues relatively easily. The amazing opportunity is the fact that, with Galileo on the horizon, all existing receivers will be obsolete in a few years, and the challenge of competing to make the best user equipment is enormous. I am excited to begin this new round of competition as soon as technical issues and specifications are finalized.

    The competitive, historical, and technical aspects of Galileo help create the face of the future of navigation. GPS is already an established system. It will continue to improve and serve as the backbone of navigation systems for many years to come. GLONASS, too, is halfway there. Russia has strong motivation to complete and support it, and with the price of oil at the current level, it will prove to be a strong competitor sooner than we may think. The recent launch of three GLONASS satellites is a good signal. Galileo is starting solidly. Will China create a fourth navigation system? It has the need to support its military operation and markets and has the financial might to pay for it. I cannot imagine a fifth system, at least not in this century. Multiple navigation systems operating independently help increase public awareness and confidence and open and expand markets quickly.

    A key factor in the success of GPS was the cooperation between GPS authorities and manufacturers. Technical details were readily available to all GPS manufacturers worldwide. In 1983, during development of the first generation of GPS receivers at Trimble, I had daily phone conversations with then Captain Karl Kovach at the GPS Control Segment to ask questions and give him feedback on GPS satellite performances that I was observing. Availability of cost-effective high-quality receivers brings the fruits of the system to the world.

    A gentleman from a GLONASS-related institute recently described the status of GLONASS as “ constellation of 14 satellites and many thousands of Javad receivers.” Generously giving me credit for my past activities, he also pointed to the importance of open, unbiased cooperation within industry. I hope Galileo’ commercial structure and objectives allow all of us to compete to develop user equipments of the highest quality and lowest cost.

    For the recent launches of Galileo and three GLONASS satellites, congratulations to all of us civilian users!