If not GNSS, then what?
If not GNSS, then what?
An interesting question.
To some, it means GNSS is so important and unique that without it, all is lost. They enthusiastically support only GNSS-centric research and development, believing that any issues that GNSS has today — such as lack of resilience — can be resolved given enough time and money. It includes pushing for the discontinuance of ground-based systems and the “re-purposing” of their resources to produce more satellites and more space-based signals. It demonstrates an admirable and true dedication to the belief that GNSS is the mission.
To others, these words have a different and darker meaning, warning of a clear and present danger. To them, it means “When (not if) GNSS is not available, what other source(s) of positioning, navigation and timing services (PNT) will be available to support GNSS users’ missions and goals?” For these purpose-driven individuals, GNSS is a means — not the mission, which is to provide the necessary positioning, navigation and/or timing performance, such as accuracy, availability, integrity, continuity and coverage, required to ensure the nation’s safety, security and economic well-being.
Unfortunately, some who have made GNSS their mission strive to convince others that it should be their mission, too!
GNSS is magic — but only when it works. It has played and will continue to play a crucial part in advancing our knowledge and abilities and supporting diverse use cases worldwide. It should and must be supported, but not to the exclusion of everything else. Recently, the magic has failed numerous times all around the world and, as a PNT community of suppliers and users, we must know we are capable of so much more.
We also know that the vast majority of civil PNT service needs are local, not global — based in part on the population density of users and their use cases. Over the years, GNSS’ accuracy and coverage have spoiled us. We even chose to see GNSS interference events as proverbial “black swans.” At the same time, the abandoning of well-engineered, resilient local solutions in favor of a global, one-size-fits-all mentality has been appealing to many. We know this approach is fraught with danger. Throwing away perfectly acceptable, resilient local means rather than enhancing them and bringing their technology into the 21st century may, as a PNT community, be our biggest regret. In many ways we have already gone too far.
I encourage our PNT community to commit to doing more, to open up our minds to design, develop, evolve, create, install, implement and operate more resilient PNT sources and more resilient user systems for which PNT services are critical inputs — especially by focusing on services that are not space-based, operate in different areas of the spectrum, are capable of higher power, and can be installed and evolved more quickly to mitigate emerging new threats. Most importantly, we all need to accept and support the true mission of our PNT community, the “why” that drives our innovative solutions: to ensure PNT services always will be available to support our safety, security and economic well-being.