Inside GNSS Media & Research

MAR-APR 2018

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22 Inside GNSS M A R C H / A P R I L 2 0 1 8 www.insidegnss.com When pressed by the PNT Adviso- ry Board during their November 2017 meeting Ligado's Executive Vice Presi- dent and Chief Legal Officer Valerie Green said that she agreed that interfer- ence testing was not the "specific intent" of the NASCTN effort. " They d id in fact develop a test methodology which, I happen to think is great and they did in fact do it (the testing)," said Green. "And as a result of that there was, in fact, data, which our engineers interpreted. at's what engi- neers do with data." It was that interpre- tation, she indicated, that supported the assertion that GPS operators and Ligado could coexist. Where's the ABC Test? One of the real questions raised by the NPEF study, however, is t he where- abouts of the ABC Assessment. The research is completed and, as of March 2017, it was supposed to be through interagency coordination and be pub- lished by May 2017. Now, nearly a year later, exper ts following the issue are wondering if it is being "slow-rolled " to keep it from being factored into the Ligado spec- trum decision. "e Adjacent Band Compatibility Report is expected to be posted to the USDOT Office of Positioning, Naviga- tion and Timing and Spectrum Man- agement website in the coming weeks," said a DoT spokesperson. at could put it outside the window of consider- ation if the EXCOM, NTIA and FCC complete their parts in a month as sug- gested. The f iling of t he NPEF test into the docket may help prevent the ABC Assessment from being ignored. The Resilient Navigation and Timing Foun- dation posted the report to the FCC docket — forcing it to be addressed by the FCC as it weighs its decision. Also seemingly missing is mention of the Air Force testing of military receiv- ers, which was being done in conjunc- tion with the ABC research. ough the results may be classified, the fact that such a report is being done is public knowledge, so it seems odd that it does not come up. "e Air Force will have a separate report on the sensitivities of the military receivers," an Air Force representative told the March 30, 2017 public workshop on the ABC Assessment. "It will be clas- sified at the appropriate level but it will be available to federal government stake- holders that need that information," he said, noting that he had already been tasked by GPS Program Director Col. Stephen Whitney. Patent Emerges In addition to the NPEF Gap Analy- sis the RNT Foundation also located and posted to the docket a patent that appears to support an accusation of fraud made in a $2 billion lawsuit over how one of Ligado's predecessor firms handled data on interference. Phil Falcone's Harbinger Capital sued Apollo Global Management and others for concealing the results of tests done in 2001 that showed that voice and data sig- nals in the band neighboring GPS would cause interference to GPS receivers. In the patent application submitted by Gary Churan, the director of systems analysis at Mobile Satellite Ventures LP (or MSV), Churan described test- ing using frequencies in the 1459-1559 MHz band. Inside GNSS asked a signal expert to look at the application to see if it did indeed reflect interference to GPS receiv- ers from telecom signals in the band neighboring GPS. e testing described in the patent missed some subtleties, said the expert, who asked to speak anonymously, but "it was a good first effort and it showed some (interference) problems." A spokesperson for Apollo Global Management in a written statement- made shortly aer the lawsuit was filed- said: "We believe the suit lacks merit and we intend to defend ourselves vig- orously." Technology has changed since that testing was done and Ligado has lowered its planned signal power and said it no longer intends to use the problematic fre- quencies from 1545 to 1559 MHz — but that's not really the issue, suggested sat- ellite industry expert Tim Farrar. "I think if the allegations made that the original license was based on fraud- ulent conduct, and the FCC decides to look into that issue, then it will be very hard, while that was ongoing, for them to grant a modification to the license," said Farrar, who has closely followed the LightSquared/Ligado debate. Interestingly, in February, the suit was put on hold until the end of the year. e preliminary conference is now scheduled for January 2, 2019. Such a long stay is unusual said Far- rar. "You can get extensions of a few weeks but you don't get extensions of nine months. So it would imply that something has happened." e real question, Farrar said, is why Harbinger would agree to delay its case? Other experts following the Ligado- GPS issue suggested the delay could be connected to Ligado — specifically that the case was put on hold so as not to undermine prospects for approval. Farrar agreed that was a possibility — but said there were many other pos- sibilities. "For example they (Apollo) could have showed Ha rbi nger what t hey planned to file, which might have made all sorts of accusations against what Har- binger did too," he said, underscoring that the idea was strictly speculation on his part. "ey (Harbinger) might have thought better of it." WASHINGTON VIEW When pressed by the PNT Advisory Board, Ligado's Valerie Green said that she agreed that interference testing was not the "specific intent" of the NASCTN effort.

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