Welcome to the Low Frequency Radio Lab
📡 Exploring Earth, Sky, and Space—One Wave at a Time
We’re an interdisciplinary research group pushing the boundaries of radio science and geophysics. At the LF Radio Lab, we study how low-frequency electromagnetic waves emerge from, and interact, with our planet. That means everything from `listening’ to lightning radio energy from 1000 miles away, probing the electrically charged plasma at the top of our atmosphere, decoding subtle signals buried in noise, to designing novel paradigm-shifting antennas.
We mix theory with hands-on experiments, field campaigns with machine learning, and engineering insight with natural curiosity. From the Blue Ridge Mountains to Antarctica, we scour the world in search of our next dataset.
An illustration of VLF wave propagation from lightning to long range. Not to scale, and just a cartoon.
What We Do
- VLF/LF Radio Propagation: Measuring and modeling how low-frequency waves (500 Hz-500 kHz for us) travel all the way around the world
- Ionospheric Remote Sensing: The electrically charged `ionosphere’, the border with space, can be probed and studied using VLF/LF waves.
- Ionosphere as a Sensor: The ionosphere response to a host of geophysical processes (solar flares, earthquakes, thunderstorms, cosmic rays) making it an ideal window to study these events.
- Space Weather: Understanding how solar storms shape our near-Earth environment, and couple into our societal infrasructure
- Field Work & Instrumentation: Building and deploying sensors in remote places—and designing the systems to analyze the data
- Machine Learning & Signal Processing: Training algorithms to find meaning in sometimes messy electromagnetic data
- Antenna Technology: Breaking longstanding boundaries in antenna design, so we can produce our own VLF/LF experiment.
- Interdisciplinary Collaboration: Finding `surprise’ connections to other fields, like cybersecurity, or plasma propulsion.
Why Our Work Matters To
Communication systems
The aviation, defense, and emergency response sectors all rely on a form of communications or radar called `over the horizon’ that can reflect off the ionosphere and skip as far as thousands of miles away. But it’s a fragile communication systems, sensitive to disruptions from the Sun and other sources. Our work improves the reliability and predictability of those systems.
(image source: US Navy)
Navigation systems
Our society is incredibly reliant on satellite navigation like GPS, including everything from aviation to cell phone networks to farming and agrlculture. But the satellite signals must cross the ionosphere to reach the ground. The ionosphere alters the signal as it passes by, and sometimes blocks it entirely, which significantly limits the accuracy of GPS signals. Our work improves the ability to forecast and predict the ionosphere, thereby helping pave the road for more accurate navigation systems.
Satellite radiation damage
Satellites in space are bombarded by energetic electrons and protons which slowly degrade and destroy the electrons, called the Van Allen radiation belts. During space weather storms, the amount of this radiation can rise by orders of magnitude, endangering critical satellite infrastructure, and astronauts in orbit. Remarkably, low frequency waves are a big part of nature’s response to these radiation belts, keeping them in check. By studying how LF waves are generated, how they interact with the radiation belts, we can better predict and perhaps even mitigate the damage from space weather disturbances.
Power grid outages
Space weather events can create intense electrical currents in space, for example the northern lights or aurora. These currents can couple into the power grid, destroying critical components and triggering power outages. Our work to forecast space weather can lead to improved lead time for the most intense space weather events, buying us time to mitigate the damage before it happens.
Lightning physics
Lightning is one of the most powerful physical processes we know. It releases potentially harmful x-ray and gamma-ray radiation, triggers casualties, power outages, and forest fires. And there’s a lot we don’t know about lightning, including how it gets started, and how often it releases the most harmful forms of radiation. But also, lightning is really incredible, for example it produces amazing light displays 50 miles high.
Submarine communication
Did you know that most radio waves are unable to reach anything submerged below salty seawater? That is, unless you can generate low frequency waves. Traditionally, LF waves are only produced by gigantic facilities between mountains or covering an entire peninsula. Our work will lead to portable LF transmitters that can also send a lot more information, which is helpful not just for submerged submarine, but also for communicating with trapped underground miners, or any subsurface communication and sensing application.
Meteorologists
Our receivers can detect and characterize lightning even from half a world away. We can use the knowledge of LF propagation, and a network of our receivers, to locate every lightning stroke on Earth (millions per day) with km-level precision. Lightning occurrence is used by weather forecasters to identify severe storms and possible tornado formation.