GPS World, January 2013
expert advice less accurateat the very high latitudes and their errors propagate into navigation radar collision avoidance and other systems Auroral effects limit the availability of GNSS at times Glonass improves GPS because of the higher orbital inclinations and hydrographic charts of the arctic are frequently quite wrong due to changes in water depth and to limited surveying frequency Increased tourism shipping and resource interest intensify the consequences of the increased risk to seafarers The advent of Galileo and Compass integrated with GPSGlonass will greatly improve the reliability of GNSS signals However navigation through the ice at places thin and navigable and at random places deep and massive ice ridges is much more than knowing where one is with respect to the center of the earth Radar helps with detection and avoidance of ice ridges but the sinking and grounding of icebreakers and commercial vessels demonstrate that much better knowledge of the environment is needed to avoid future disasters The thousandkilometer shorter route over the Pole can be very expensive and not necessarily the fastest one However the increased activity in Geringer critiqued an attitude on the part of GNSS professionals in which their attention is more devoted to the how of obtaining the information than to the effects that future changes might have on the users the Arctic is going to continue and it is mandatory that safety factors be given greater attention by the International Maritime Organization satellite compasses are reliable where magnetic ones are not but the IMO has not approved them and by the hydrographic services of the affected areas From Farm to Front Office Jim Geringer former governor of Wyoming now a director of ESRI and a member of the GPS Excom gave as usual a very entertaining presentation GPS GNSS From the Farm to the Front Office with highly interesting examples of the very broad and deep impact of GNSS on society including financial statistics and object lessons in the misuse or inaccurate use of geospatial data Geringer was an engineer before he went into politics and that came through clearly in the presentations even though he was very self effacing concerning his technical credentials He gave amusing examples not all from Apple of the effects of combining current and historical geospatial data such as airport runways shown in topography layers obtained before leveling the airport areas and a road running across the valley filled by Hoover Dam Geringer critiqued an attitude on the part of GNSS professionals in which their attention is more devoted to the how of obtaining the information than to the effects that future changes might have on the users He discussed policy challenges presented by the FCC mandate to find 500MHz of spectrum for high speed wireless data by affordability by the potential for jamming and spoofing It was good to be reminded of the awesome realized economic benefits of GNSS the manifold applications which GNSS systems enable and the ease with which this potential can be limited or actually damaged by pursuit of other worthwhile objectives which are politically favored or which bring short term revenue into the treasury at the expense of GNSS system requirements in bandwidth The less obvious but equally or more beneficial economic benefits of high accuracy GNSS and the impact of actual lives lost or resources untappedwere illustratedand quantified in Geringers broad presentation One hopes that this presentation will be or has been seen at High GSA and policy levels in the FCC and NTIA Geringers presentation provides a nice segue into a presentation by LightSquared Lessons Learned Rich Lee of Greenwood Telecommunications Consultants LLC and iPosi Entitled Lessons Learned from the GPS LightSquared Proceeding it was an assessment of the opportunities missed and damage done in the drive to enable the use of spectrum adjacent to GNSS frequencies for 4G LTE wholesale services through high power Auxiliary Terrestrial Components ATCs using MSS spectrum reallocated or repurposed to the purpose under a conditional waiver by the Chairman of the FCC Julius Genachowski on a recommendation by the International Bureau of the FCC According to Lee Greenwood was called in to solve if solutions exist the problem of the spectrum collision between the LSQ design and GPS after the collision occurred He likened the role of Greenwood to that of a tow truck operator called in to clear up a collision after the impacts Lee served on the TWG Temporary Working Group as head of the cellular subgroup and headed the NTIA Excom cellular tests The presentation was very good technically in both its detailed and more strategic aspects but both the history described and GPS World January 2013 www gpsworld com 12
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