Avi Rosenthal: A Risky Tradeoff in the Race for GPS Backup

Why It Matters

The decision will shape national safety infrastructure and could impose massive replacement expenses, while failing to deliver a robust GPS alternative. Choosing a less disruptive PNT approach would protect existing IoT ecosystems and ensure broader coverage.

Key Takeaways

• NextNav seeks high‑power 900 MHz PNT, threatens low‑power IoT
• Interference could cripple safety sensors, fire alarms, medical alerts
• Replacement cost for sub‑GHz devices could exceed $100 billion
• Experts say solution fails for aviation, maritime, rural coverage
• Alternative PNT systems exist without reallocating critical spectrum

Pulse Analysis

The United States’ reliance on GPS has exposed a strategic vulnerability as jamming and spoofing incidents rise worldwide. Policymakers are under pressure to deliver a resilient backup, but any solution must coexist with the dense fabric of low‑power, unlicensed devices that power smart homes, industrial monitoring, and critical safety systems. Ignoring the interdependence of these ecosystems risks creating a new class of national‑security threats, especially as emergency responders and utility operators depend on sub‑GHz connectivity for reliable, long‑range communication.

NextNav’s plan to flood the lower 900 MHz band with high‑power PNT signals promises rapid deployment but carries significant technical and economic downsides. The band’s predictable propagation characteristics have enabled battery‑life‑optimized sensors to function for years without maintenance. Introducing 5G‑grade power levels would raise the noise floor, forcing devices like motion detectors and carbon‑monoxide alarms to boost transmission strength—potentially by a factor of 500—draining batteries and shortening device lifespans. Industry analyses estimate that retrofitting or replacing the affected hardware could exceed $100 billion, a cost dwarfing current federal PNT research budgets.

Fortunately, a suite of alternative backup technologies exists that avoid commandeering the sub‑GHz spectrum. Options such as eLoran, Broadcast Positioning System, satellite augmentation, and fiber‑based time distribution can deliver nationwide coverage without jeopardizing existing IoT deployments. Policymakers should prioritize these less intrusive solutions, leveraging existing infrastructure while preserving the integrity of life‑safety networks. A balanced approach will safeguard both the nation’s navigation resilience and the billions of devices that underpin modern safety and automation.