Podcast Summary: T-Minus Space Daily

Episode Title: Navigating the Arctic Circle with Communication Satellites
Host: Maria Varmazes (N2K Networks)
Guest: Dr. Zak Kassas, Professor, Electrical and Computer Engineering, The Ohio State University
Date: January 17, 2026

Overview

This episode explores groundbreaking research into using signals from commercial low Earth orbit (LEO) communication satellites, such as Starlink and OneWeb, as navigation aids in regions where traditional GPS coverage is unreliable, specifically the Arctic Circle. Dr. Zak Kassas discusses his award-winning research, the technical challenges, and the sustainability implications for the future of global navigation systems.

Key Discussion Points & Insights

1. Background and Significance of the Research

• Dr. Kassas (02:20–03:51):
  • Leads the Center for Automated Vehicle Research with Multimodal Assured Navigation ("CARMEN").
  • Focuses on resilient and accurate navigation systems, crucial for safety-critical applications (e.g., aviation, military ops).
• Acknowledgement of the limitations and vulnerabilities of current GPS infrastructure, especially in the polar regions.

Quote:
“GPS is a wonderful system… but the limitations are null. In recent years, it's been extremely vulnerable…especially in safety-critical systems like aviation, like military operations and so on.”
— Dr. Zak Kassas (04:50)

2. Genesis and Evolution of the Project

• Research started in 2017, foreseeing the expansion ("booming") of LEO mega-constellations (e.g., Starlink, OneWeb) originally designed for broadband, not navigation (03:51–05:48).
• Early experiments with Orbcomm and Iridium paved the way for successful trials with Starlink.
  • 2021: First to demonstrate 10-meter accuracy location determination using only Starlink signals.
  • Demonstrated navigation for ground vehicles, high-altitude balloons (~80,000 ft), UAVs, and most recently, vessels in the Arctic.
  • Recent Arctic trial: navigated a vessel for ~8 km with error in the tens of meters.

Quote:
“We were the first to demonstrate in the world that…you can actually pinpoint your location to within about 10 meters or so with Starlink satellites alone.”
— Dr. Kassas (05:51)

3. Technical Aspects: Exploiting Communication Signals for Navigation

• These navigation techniques are passive and “opportunistic,” relying on decoding publicly available, non-navigation communication signals (OFDM frames, similar to 4G/5G) (09:26–10:50).
• Biggest technical hurdles:
  1. Signal Decoding: The specifics of what Starlink and other constellations transmit are not public; the research involved reverse-engineering these signals.
  2. Satellite Position Uncertainty: Precise, real-time satellite location data (ephemeris) are proprietary; public information is coarse and inconsistently updated.
  3. Synchronization: They use only synchronization sequences (not data traffic or customer-sensitive data) to derive positioning.

Quote:
“We are only listening to what we call synchro. We are not listening to data traffic, nor do we have that capability or interest. We’re listening to synchronization sequences that are out there that allow us to navigate.”
— Dr. Kassas (21:23)

4. Results From the Arctic Trials

• Discovery: Starlink signals in the Arctic are not only usable for navigation, but technically “more beautiful” (cleaner, more robust) than in other regions (07:59–08:02).
• Arctic is of unique geopolitical and security significance; GPS coverage here is limited (07:05–07:37).
• Demonstration proves LEO constellations enable resilient navigation in GPS-challenged zones.

Quote:
“To our surprise, they were not only useful, they are actually more beautiful … than many places where we tested this.”
— Dr. Kassas (08:02)

5. Implications for Resilience & Future of Navigation

• Current Problems:
  • GPS is increasingly vulnerable to jamming/spoofing (13:32).
  • Solutions like deploying more satellites in MEO (medium Earth orbit) are seen as obsolete thinking.
• Schools of Thought on GPS Alternatives (16:20–17:48):
  1. Dedicated LEO Navigation Constellations: Build new satellite networks for PNT (Positioning, Navigation, Timing).
  2. Dual-Purpose Signals: Have comms constellations intentionally carry navigation payloads.
  3. Fully Opportunistic (Kassas' Approach): Use whatever signals exist, regardless of intended purpose; allows using dedicated, dual-purpose, and pure comm signals for PNT.
• Sustainability:
  • Opportunistic approaches avoid spectrum congestion and Kessler syndrome (overcrowding LEO with satellites).
  • “Cognitive sensing and opportunistic navigation” leverages all available transmissions for navigation, minimizing unnecessary new satellites and spectrum allocation.

Quote:
“If you do not have enough taxis in a city, the solution is not to throw in more taxis… Why don’t we repurpose cars that are driving around for transporting humans and goods? …That’s the opportunistic approach.”
— Dr. Kassas (20:14)

6. Industry & Policy Reactions

• Satellite operators have contacted Dr. Kassas and team about the work (21:12–21:37).
• Some satellite providers learn new things about their own systems from these academic analyses.
• The technique is legal: “the signal is out there,” listening to publicly transmitted synchronization sequences.

Memorable Quotes & Timestamps

• On GPS Vulnerabilities:
  “We got so used to it in our daily lives and more importantly and more dangerously in safety critical systems like aviation, like military operations and so on.” (04:50)

• On Technical Achievement:
  “We were the first to demonstrate in the world that…you can actually pinpoint your location to within about 10 meters or so with Starlink satellites alone.” (05:51)

• On Discovering Clean Signals in the Arctic:
  “They were not only useful, they are actually more beautiful…than many places where we tested this.” (08:02)

• On Opportunistic Navigation:
  “Think of Uber… Why don’t we repurpose cars that are driving around…” (20:11–20:19)

• On Industry Impact:
  “Actually, some of them even learn about their system from what we do.” (21:45)

Important Timestamps

• [02:20] — Dr. Kassas introduces his background and research lab.
• [03:51] — Research origins and rationale for using LEO satellites.
• [05:51] — Milestone: first practical demonstration with Starlink signals.
• [07:05] — Motivations for Arctic tests, highlighting GPS weaknesses at the poles.
• [08:02] — Discovery of superior signal quality in the Arctic.
• [09:26] — Technical breakdown of the signals and methods used in the research.
• [13:32] — The broader context of GPS jamming/spoofing and the search for resilient alternatives.
• [16:20] — Explanation of competing future navigation strategies (dedicated, dual-use, opportunistic).
• [20:11] — Analogy to Uber: the logic behind opportunistic reuse of resources.
• [21:12] — Industry engagement and ethical considerations.

Tone and Style

The conversation is technical yet approachable, blending genuine curiosity (Maria Varmazes) with detailed yet accessible explanations (Dr. Kassas). The tone is optimistic about the future of space-enabled navigation, insisting on the need for sustainable, scalable solutions as LEO constellations proliferate.

Conclusion

Dr. Kassas’ research demonstrates that commercial LEO satellites—as they currently operate—can serve as effective ad-hoc navigation beacons, enabling PNT resiliency even in GPS-starved environments like the Arctic. The fully opportunistic, spectrum- and satellite-efficient methods pioneered by his team may be a glimpse into a more robust, sustainable, and innovative future for global navigation, far beyond traditional GNSS architectures.