The filings do not specify what the tests would be for, but they hint at a new type of technology or wireless service, noting that the project would involve prototypes designed to support "innovative communications capabilities and functionalities."

Even more intriguing is that Amazon listed Neil Woodward as the main contact on the filings. Woodward, a retired NASA astronaut who joined Amazon in 2008, is now a senior manager for Prime Air, the team in charge of Amazon's drone-delivery effort, according to his LinkedIn page.

That suggests the tests could involve some kind of communications system to control Amazon's delivery drones. But the details in the filings could also point to a wireless service designed to work with mobile handsets, such as Amazon's Kindle tablets, or perhaps the Echo home speakers that Amazon sells.