Loon LLC is an Alphabet Inc. subsidiary working on providing Internet access to rural and remote areas. The company uses high-altitude balloons placed in the stratosphere at an altitude of 18 km (11 mi) to 25 km (16 mi) to create an aerial wireless network with up to 4G-LTE speeds.
A reference to the balloons used, Project Loon began as a research and development project by X (formerly Google X), but later spun out into a separate company in July 2018.
The balloons are maneuvered by adjusting their altitude in the stratosphere to float to a wind layer after identifying the wind layer with the desired speed and direction using wind data from the National Oceanic and Atmospheric Administration (NOAA).
Users of the service connect to the balloon network using a special Internet antenna attached to their building. The signal travels through the balloon network from balloon to balloon, then to a ground-based station connected to an Internet service provider (ISP), then onto the global Internet.
The system aims to bring Internet access to remote and rural areas poorly served by existing provisions, and to improve communication during natural disasters to affected regions. Key people involved in the project include Rich DeVaul, chief technical architect, who is also an expert on wearable technology; Mike Cassidy, a project leader; and Cyrus Behroozi, a networking and telecommunication lead.
The balloons use patch antennas – which are directional antennas – to transmit signals to ground stations or LTE users. Some smartphones with Google SIM cards can use Google Internet services. The whole infrastructure is based on LTE; the eNodeB component (the equivalent of the "base station" that talks directly to handsets) is carried in the balloon.