On April 23, 2008, the Southern California Chapter of the ION held a meeting, hosted by NavCom in Torrance, CA. The meeting included a presentation from Dr. Per Enge of Stanford University on the subject of the future GNSS-based Aviation Precision Approach. A short biography and abstract of the meeting follows.
Capsule Biography of Dr. Per Enge
Per Enge is a professor at Stanford University, where he directs the Center for Position Navigation and Time. In the distant past, he helped to design solid state Loran transmitters, and he still works on enhanced Loran. In the not so distant past, he led the development of radio beacons to broadcast differential corrections at medium frequency to marine and land-based users of GPS. These days, he spends most of his time on the local and wide area augmentation systems. Per Enge has received the Kepler, Thurlow and Burka Awards from the ION for his work. He is also a Member of the National Academy of Engineering and a Fellow of the ION and the IEEE.
By 2020, GNSS will provide precision approach guidance worldwide. This capability will be born of three important technologies. First and foremost, avionics will receive two frequencies: L1/E1 and L5/E5b. This frequency diversity will do much to obviate the impact of ionospheric storms and radio frequency interference. Second, a multiplicity of data broadcasts will be used to convey integrity information from the ground to the airborne users. These will include the GNSS satellites themselves, geostationary satellites and regional networks of VHF transmitters and airport specific VHF data broadcast (VDB). However, the most important change will be the most subtle. The fault monitoring burden will be split between the aircraft and the supporting ground systems in a new way. This new integrity architecture for aviation is the subject of this talk.
On March 11, 2008, the Southern California Chapter of the ION held a meeting, hosted by Raytheon in El Segundo, CA. The meeting included a presentation from Frank Boon of Septentrio on the releasable activities of Septentrio. A short biography and abstract of the meeting follows.
Curriculum Vitae of Frank Boon:
Currently, Mr. Boon is the Head of Research at Septentrio, responsible for the development and evaluation of novel GNSS technology, technological strategy and team management. He previously was an R&D Engineer at the Dutch Ministry of Transport, Survey Department at Delft, in the Netherlands, working on high-end GPS/INS systems in Photogrammetry. He holds an MSc degree from the Delft University of Technology, where he did research on OTF GNSS carrier ambiguity resolution techniques. He has published extensively in the fields of GNSS systems and applications.
Abstract of Frank Boon’s Talk:
Boon will present aspects of the Safety-of-Life service scheduled within the Galileo system. Emphasis will be given to the SIS data-stream related to the Safety-of-Life service and its relation to the Hazardous and/or Misleading Information Probability Computation Algorithm (HPCA).
A comparison will be made between Galileo’s HPCA and the HMI statistics in the WAAS/EGNOS protection level computation as well as standard RAIM.
On February 9, 2008, the Southern California Chapter of the ION held a meeting, hosted by NavCom in Torrance, CA. The meeting included a presentation from Gaylord Green, Director of the Gravity Probe B program at Stanford. A short biography and abstract of the meeting follows.
Brief Resume of Gaylord Green
Col Gaylord Green (Ret) is a former director of the GPS program and was in the original program office cadre when the program was initiated in charge of the space segment. Additionally, Gaylord directed the guidance shop for the Minuteman/Peacekeeper inertial guidance systems. Since retiring from the Air Force, he is exploring space-time with the world’s most accurate gyroscope in NASA’s Gravity Probe B program.
Abstract of Colonel Gaylord Green’s Talk
Gravity Probe B (GP-B) is a physics mission to experimentally investigate Albert Einstein’s 1916 general theory of relativity. GB-B uses four spherical gyroscopes and a telescope, housed in a satellite orbiting 642 km (400 mi) above the Earth, to measure in a new way, and with unprecedented accuracy, two extraordinary effects predicted by the general theory of relativity:
The geodetic effect—the amount by which the Earth warps the local space-time in which it resides.
The frame-dragging effect—the amount by which the rotating Earth drags its local space-time around with it.
The GP-B experiment tests these two effects by precisely measuring the precession (displacement) angles of the spin axes of the four gyros over the course of a year and comparing these experimental results with predictions from Einstein’s theory.
The Institute of Navigation Southern California Section meeting was hosted by The Aerospace Corporation and held in El Segundo on March 31st. At the start of the meeting the Southern California section chair, Clyde Edgar and California Polytechnic University Advisor, Dr. Ilir Progri presented a ION scholarship award to Lijia Chen, the first Southern California section ION graduate scholarship award recipient as part of the ION student outreach program. Next, our distinguished guest speaker John Lavrakas, ION Western Region Vice president, spoke about the ION, its purpose, membership benefits, and the role it plays in furthering the art and science of navigation. John then followed with a technical presentation on GPS “An Overview of Civil Monitoring”. The meeting was well attended and was followed by an spirited question and answer period. Please see the following documents for more information: An Overview of Civil Monitoring The ION and Membership Benefits
The Institute of Navigation Southern California Section October 20 meeting was hosted by Boeing Space Systems and held in the Boeing Seal Beach Complex, Building 86. The meeting was well attended even though freeways were flooded and a large amount of rain was falling. Mr. Frank Czopek, GPS Block II/IIA Satellite Program Manager, presented an historical overview of the GPS satellite program at Seal Beach and showed slides of the manufacturing floor facilities in its heyday.
After his very interesting presentation Frank led a walking tour of the facilities highlighting the immense Thermo-Vac Chambers, Spin table, and Manufacturing room area. He described what the areas were like during the 3 shift GPS SV manufacturing schedule and also discussed a little known incident by eco-terrorists that resulted in actual damage to a space vehicle, the infamous ax incident where a space vehicle was attacked and damaged with an ax.
The tour ended with a viewing of a glass encased chrome plated shovel, the shovel that Werner Von Braun used to dedicate the facility for the Saturn Project in 1966. The property used for manufacture of the Block I, II and IIA satellites is designated to be sold later this year as it is surplus to Boeing’s needs. The meeting attendees grouped around the Navstar Monument for a photograph at the end of the meeting. The monument depicts each satellite manufactured in the facilities and when it was launched.
The Institute of Navigation Southern California Section meeting held on Thursday, April 22 was well attended and hosted by Raytheon in El Segundo. 1Lt. Bryan Titus of the GPS JPO spoke on behalf of Mr. Tom Stansell on “The L1C Stewardship Project”, an IGEB sponsored program to actively solicit inputs from interested parties on the implementation of the new GPS L1C signal. The Interagency GPS Executive Board (IGEB) has funded the stewardship project (L1C Project) to determine how best to improve the L1 civil signal on GPS III satellites. The GPS JPO and the USGS in Pasadena are co-sponsors of the project.
A key purpose is to determine what users and companies want in a new signal structure. This is historic, because for the first time the U.S. Government is seeking advice and comment from experts around the world on a proposed new civil signal. 1Lt. Titus requested that the presentation and questionnaire form be made available to the ION website and welcomes questionnaire inputs.