Patent ID: 9612325
Date: 2017-04-04
CPC Classifications: G01S

Claim:
1. A measurement method, the method comprising: transmitting a first signal from an originator device to a transponder device, the first signal having a first carrier frequency; determining a carrier phase of the first signal at the transponder device; transmitting a second signal from the transponder device to the originator device, the second signal having a second carrier frequency; determining a carrier phase of the second signal at the originator device; estimating a relative distance between the originator device and the transponder device using the carrier phase of the first carrier signal and the carrier phase of the second carrier signal, wherein the relative distance wraps across an upper boundary and a lower boundary; adjusting the relative distance by unwrapping the relative distance outside at least one of the upper boundary and the lower boundary; and using the adjusted relative distance to determine a total distance between the originator device and the transponder device.