US Patent 9689955 Ranging system using active radio frequency (RF) nodes

A ranging system includes at least one beacon and a control module. The at least one beacon is configured to scan each segment in a plurality of segments of an arc with a narrow radio frequency (RF) beam and receive a response signal from an end user node in at least one segment. Each segment of the arc is scanned at a specified time interval. The control module is configured to communicate with the at least one beacon. The control module is further configured to calculate at least one of an angle-of-arrival (AOA) and a time-of-flight (TOF) of a response signal from the end user node to the beacon and generate an end user node location relative to a beacon location.