GPS World, January 2013

expert advice continuation of GPS III as planned with the addition of simpler lighter satellites with reduced diversity of signals to replace the aging GPS satellites now on orbit beyond their design life Compass Professor Jingnan Liu of the GNSS Research Center of Wuhan University gave what most observers thought was the first comprehensive and data intensive description of Precise Positioning results with the COMPASS Beidou system He showed that the Beidou regional system from which he presented copious data can currently provide standard positioning service with 10M horizontal and 20M vertical accuracies at 95 confidence level He also showed that results with Beidou plus GPS are 10 20 better than GPS alone He provided results for surveying for ground based augmentation for RTK PPP clock stability orbital statistics wide area differential and many other metrics of PNT Professor Parkinson noted in appreciating the presentation that it was the first detailed release of so much technical data on COMPASS performance The results noted above were obtained with 4GEO 5 IGSO 2MEO satellites The constellation is expected to grow to 5GEO 5IGSO 4MEOs by the end of 2012 and to 5GEOs 3IGSOs 27 MEOs by 2020 for a global service The amount of data and the diversity application and instrumentation of the data were truly impressive GPS Modernization Dr Keoki Jackson of Lockheed Martin presented a comprehensive review of GPS Modernization with charts which described the evolution of GPS from Block I to Block III He depicted the program as on schedule for delivery of the first GPS III vehicle in May 2014 with a 2015 launch Most of this material was the same as reported from the AFCEA GC 12 program in GPS World earlier this year A matrix comparing the attributes of GPS III with GPSII and beneficial outcomes from Backto Basics Investments were key takeaways Ground Control Ray Kolibaba of Raytheon presented a detailed overview of the OCX program the next generation Operational Control System This presentation also emphasized improvements in program management simplification of development practices extensive use of commercial development methods and predicted on time delivery with all of the attributes needed for both GPS III and the existing constellation Military User Equipment Col Bernie Gruber Director of the GPS Directorate gave an update on current activities with emphasis on progress in Military User Equipment MGUE development This material was somewhat further advanced in schedule than the equivalent May 2012 time frame in which the same subject was presented in much detail at the AFCEA GC 12 meeting at the Directorate The currently hot topics of jamming and spoofing threats countermeasures and affordability were prominent in the Stanford PNT Symposium Stanford University professors Brad Parkinson Jim Spilker Per Enge Leo Hollberg Mark Kasevich Sherman Lo and Tom Langenstein among others conduct an annual PNT Symposium organized by Tom Langenstein The presentations given by the invited speakers are generally very good indeed and are selected to communicate new technology new applications and new science The subjects range from breakthroughs in scientific understanding of phenomena revealed by or for GNSS and other sensor systems to strategic political and economic issues in GNSS internationally and nationally in defense and civil sectors in universities on farms and in oil fields The by invitation only audience consists of people whose expertise approximates that of the speakers in their own corners of the field This article summarizes the principal messages not in order of presentation nor in detail but grouped by general subject matter Those presentations given short paragraphs here are more generally available and have been presented in other larger scale venues No inference should be drawn about merit all were very worthwhile and I learned much from each JDL presentation Some of the key achievements for 2012 listed were the release of BAAs Broad Agency Announcements for NavSat studies and the completion of a Congressional Report on Cost Effective GPS Launch of GPS IIF 3 and delivery of GPS IIF 4 56 7 were also noted Security Certification for MUE cards was a very noteworthy achievement which will make future MGUE development and utilization much easier for the challenging jamming and spoofing environment which is expected The themes of affordability and jamming and spoofing threats were dominant in this review as well General PNT Norvald Kjerstad is a professor of Nautical Science at Aalesund University College and a long time professional navigator in academic geophysical and shipping communities His paper vividly depicted the risks brought about by climate change by increased commercial interest in shipping and mineral resource exploration in the Arctic region and by the very limited navigation infrastructure and limited communications assets Arctic Navigation Both DGPS and SBAS systems are quite limited in the arctic magnetic compass systems are GPS World January 2013 www gpsworld com 10