Method and system for demodulating a digital pulse recognition signal in a light based positioning system using a Fourier transform
US8436896B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 19, 2012 |
| Grant date | May 7, 2013 |
| Priority date | — |
| Expiry date | Jun 19, 2032 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01S5/16
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
In one aspect, the present disclosure relates to a method for demodulating a modulated light signal in a light based positioning system. In some embodiments, the method includes receiving a modulated light signal at a device, the modulated light signal transmitting an arbitrary identifier of a light source, recording the modulated light signal using a rolling shutter image sensor to create a raw image having alternating spaced apart stripes, subtracting background information from the raw image to create an isolated image, taking a Fourier transform of an image representative of the isolated image to calculate a Fourier transformed signal, and determining the arbitrary identifier of the light source based on the Fourier transformed signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.