The Possibility in RNSS Frequency Expansion for Resilient PNT

JaeHee Noh*, Deok Won Lim, Nayoung Youn

This paper addresses trends in Radionavigation Satellite Service (RNSS) frequency expansion for Resilient Positioning, Navigation, and Timing (PNT). In response to L-band congestion, the International Telecommunication Union (ITU) is considering a new RNSS frequency allocation in the C-band (5030-5250 MHz) as part of the WRC-31 preliminary agenda item 2.9. C-band could offers advantages such as like reduced ionospheric effects and the potential for smaller antennas. Concurrently, new architectures and business models considering like low Earth orbit (LEO) PNT and space-based alternative PNT (A- PNT) are emerging from the 'NewSpace' economy, accelerating the development of technological approaches for resilient PNT solutions. These commercial platforms, offering “PNT-as-a-Service”, utilize the C- band to deliver more secure, anti-spoofing signals with enhanced accuracy. The ITU’s strategic discussions on C-band frequency allocation are directly empowering a new wave of innovative, commercially- driven LEO PNT solutions. This convergence of regulatory foresight and technological development will ultimately lead to a more stable, secure, and diversified PNT ecosystem, capable of meeting the demands of critical infrastructure and next-generation applications.

Keywords: RNSS, resilient PNT, C-band