GPS World, September 2010

DEFENSE Space Warfighter delivered in a reasonable proximity to each other Not to make excuses but as it relates to GPS this is just hard to accomplish because it involves a span of control and accountability that is almost infinite Many in the community recognize this reality which has allowed the Air Force to set appropriate and realistic expectations so real capability can be delivered That being said there are prudent things that can and are being done to speed the deployment of capability and set appropriate expectations The most significant has been to broadcast the M code L2C and soon L5 signals from space to allow civil and military user equipment manufacturers to begin development and testing of their next generation of receivers This gives industry a jump while the U S Air Force continues to develop the C2 capability and the nextgeneration signal monitoring capability required to ensure signal in space performance integrity Also building the modernization programs with a strong mission assurance foundation is a major step forward We understand the lessons learned that established the baseline for the current Block II systems delivery the Block III systems are built on a solid acquisition strategy of reduced risk and increase execution confidence DJ What is one of the biggest GPS enterprise challenges and what are some of your thoughts on the way ahead DM Thats easy Don ensuring global PNT services are not interrupted as the United States continues to modernize GPS If we dont continue to develop a more robust means of ensuring user equipment compatibility even a small number of non system compatible receivers military or civilian can significantly delay the delivery of critical modernized capability for everyone Let me explain and provide some thoughts Since its initial design in the early 1970s GPS has evolved in both capability and complexity In the early days systems engineering across the space control and user segments was relatively straightforward The GPS Joint Program Office developed all military user equipment and was able to rigorously ensure all specifications were verified prior to fielding Over the past 20 years however GPS has become ubiquitous throughout the Department of Defense with tailored satellite navigation solutions developed and acquired by dozens of program offices to support hundreds of unique requirements Meanwhile commercial GPS is one of the foundations of the Information Age with GPS receivers produced in quantities approaching half a billion devices per year The model of simply providing policies standards and interface control documents without providing a means to certify receiver compliance is becoming more challenging due to the continued growth in both military and civil applications for PNT the competitive nature associated with user system applications and performance and the increased complexity of GPS Furthermore it is especially difficult fielding upgrades to an established system like GPS while maintaining backwards compatibility with previously fielded equipment These challenges are further exacerbated by difficulties associated with synchronizing the lengthy timelines associated with fielding ground segment satellite and user equipment upgrades Recent highly isolated incidents involving civilian and military receiver and other manufacturers have highlighted the significant impact a very small number of receivers experiencing compatibility issues can have on the entire enterprise of worldwide users In addition a number of cases associated with improper receiver integration into major weapon systems have delayed system fielding as well not allowed the weapon system to best optimize GPS to the overall weapon systems performance Therefore it is my opinion to ensure worldwide PNT services are not interrupted as we continue to modernize the GPS a more robust means of ensuring compatibility needs to be explored I would like to stop and make a note here by we I mean all the DoD and civil agency stakeholders This means we need to not only continue to release building codes but we need to develop a capability to be more involved in the development integration and testing of new military and possibly civil user equipment We have recently taken a number of big steps in this direction First we are currently significantly increasing the number of civil and military GPS receivers in our government testing labs This will enable us to run tests against a wider variety of receivers to gain higher confidence before we deploy system upgrades Second we recognize that we need to ensure that our signal specifications for both military and civil users are as clear as we can make them User community representatives are already encouraged to be full participants in appropriate interfacecontrol working groups We further recognize that there is no substitute for thorough testing and hence fully appreciate the importance of deploying signal inspace capabilities as early as possible on predictable schedules so user equipment can be field tested prior to market release or operational deployment Third we are developing new upgrade fielding methodology whereby when we deploy system upgrades we will take a more methodical approach and whenever possible field upgrades to smaller segments of receivers to prove compatibility without exposing all operational assets simultaneously We will also apply a new software sustainment model to future military GPS user equipment MGUE to ensure that inevitable system changes are systematically and rigorously executed with minimal impact on DOD programs Finally we are investigating the establishment of something similar to an Underwriters Laboratories service to help support military programs with integrating GPS into their weapon systems during development The teams associated with such lab services would support program design reviews as well as help develop the validation criteria for overall system acceptance In addition we are also starting discussions with key GPS civil receiver developers on how we might be able to provide a similar service to GPS World September 2010 www gpsworld com 48