Dual frequency ranging with calculated integer wavelength and phase difference
AssigneeRTR Technologies, Inc.
InventorsDavid Farrell, Thomas Pattison
Life of this patent
Estimating the term…
Abstract
The embodiments described herein provide ranging capabilities in RF-opaque environments, such as a jungle, utilizing transponders located on a property line. In particular, the embodiments described herein provide for determining a distance to a property line from a ranging device. The transponders are located on the property line and are separated from each other by a known distance. The ranging device transmits RF signals to the transponders, and receives RF signals returned by the transponders on a different frequency. The ranging device uses information about the transmitted and received RF signals and the known distance to calculate a distance from the ranging device to the property line.
Claims20
A ranging system, comprising:
- a range detector comprising:
- circuitry configured to transmit a first Radio Frequency (RF) signal at a first frequency, and to receive a second RF signal at a second frequency from a transponder in response to the first RF signal;
- and
- circuitry configured to calculate a distance to the transponder based on the first RF signal and the second RF signal by:
- calculating an estimated distance based on an integer number of wavelengths between the transponder and the range detector;
- calculating a sub-wavelength distance based on a phase difference between the first RF signal and the second RF signal;
- and
- calculating the distance to the transponder based on a sum of the estimated distance and the sub-wavelength distance.
A method of operating a ranging system, the method comprising:
- transmitting, from a range detector, a first Radio Frequency (RF) signal at a first frequency;
- receiving, at the range detector, a second RF signal at a second frequency from a transponder in response to the first RF signal;
- and
- calculating a distance from the range detector to the transponder based on the first RF signal and the second RF signal by:
- calculating an estimated distance based on an integer number of wavelengths between the transponder and the range detector;
- calculating a sub-wavelength distance based on a phase difference between the first RF signal and the second RF signal;
- and
- calculating the distance to the transponder based on a sum of the estimated distance and the sub-wavelength distance.
A non-transitory computer readable medium embodying programmed instructions which, when executed by a processor of a range detector, are operable for performing a method comprising:
- transmitting, from the range detector, a first Radio Frequency (RF) signal at a first frequency;
- receiving, at the range detector, a second RF signal at a second frequency from a transponder in response to the first RF signal;
- and
- calculating a distance from the range detector to the transponder based on the first RF signal and the second RF signal by:
- calculating an estimated distance based on an integer number of wavelengths between the transponder and the range detector;
- calculating a sub-wavelength distance based on a phase difference between the first RF signal and the second RF signal;
- and
- calculating the distance to the transponder based on a sum of the estimated distance and the sub-wavelength distance.
Dependencies are inferred from the claim text.