Amazon.com, Inc.
Using pseudorandom signals transmitted from distributed sources in ranging operations

Abstract:

Ranging systems operate based on the transmission and receipt of pseudorandom sequences. Pseudorandom sequences may be generated and assigned to specific transmitters, which may operate simultaneously to transmit signals including the pseudorandom sequences. A receiver may be programmed to recognize the specific pseudorandom sequences within data captured by the receiver, and to associate the pseudorandom sequences with the transmitters that transmitted them. Upon identifying the pseudorandom sequences, the receiver or one or more associated components may calculate times of flight of signals transmitted by the respective transmitters. Such times of flight may be used to calculate distances to one or more objects from which the signals were reflected.