In June of 2013 Google unveiled Google Loon, the latest in a long line of similar projects that will use balloons to deliver broadband and wireless services to under-served or emergency prone areas. Project Loon will use balloons 49 feet wide stationed 12 miles above the planet, well above the range of commercial aircraft. Ground base stations sixty miles apart communicate with solar-powered radio transmitters affixed to the balloons, and Google steers the balloons using wind as they ride the 40th parallel.
As the company expands its trials into portions of the States, Google is promising that radiation from the company's ongoing trial of broadband balloons is no threat to humans.
In a new letter to the FCC, Google notes that the balloons, which will deliver broadband to under-served region from 60,000 feet, are high enough that any RF energy received by humans would be well within limits for airborne and terrestrial transmitters in the 71-76 and 81-86 GHz bands (the E-band).
"Some commenting parties worry that the radio-frequency (RF) energy from Google's proposed testing could harm humans, animals, or plants in the vicinity of the test operations," states the letter. "Although we respect that the commenters' concerns are genuinely held, there is no factual basis for them."
"Even if an airborne transmitter were aimed precisely at a person on the ground directly below it, the signal strength received on the ground would be millions of times weaker than FCC limits," Google explains.
Google's been experimenting with Loon broadband balloons in Sri Lanka, but has applied to more formally test the service across the United States. The company has repeatedly stated that the goal is to work with existing carriers to shore up lagging coverage, not to compete directly with them. Though as services like Google Fiber and Google Fi expand, it's not unlikely Loon could find itself feeding other Google direct-to-consumer broadband offerings.