Positioning system based on visible light communications
A position tracking system includes one or more beacon transmitters and one or more beacon receiver systems configured to be disposed on an object. Each of the one or more beacon receiver systems includes one or more photodetectors configured to receive signals from the one or more beacon transmitters, and an analog-to-digital convertor to convert analog signals received by the one or more photodetectors to digital signals. Each of the one or more beacon receiver systems also includes a memory and a processor configured to execute instructions stored on the memory. The instructions includes receiving signals collected by the one or more photodetectors, converting the received signals to digital signals, and processing the digital signals.
1. A position tracking system, comprising:
one or more beacon transmitters;
one or more beacon receiver systems configured to be disposed on an object, and wherein each of the one or more beacon receiver systems comprises:
a motion sensor to collect motion data of the object;
a plurality of photodetectors configured to receive signals from the one or more beacon transmitters;
an analog-to-digital convertor to convert analog signals received by the plurality of photodetectors to digital signals;
a memory; and
a processor configured to execute instructions stored on the memory comprising instructions for:
receiving signals collected by the plurality of photodetectors;
converting the received signals to digital signals;
processing the digital signals;
computing a location of the object based on an analysis of combination of the processed digital signals and the motion data of the object; and
wherein the plurality of photodetectors are disposed densely along a vertical axis as compared to the plurality of photodetectors disposed along a horizontal axis.
2. The position tracking system of claim 1 , wherein the one or more beacon transmitters and each of the plurality of photodetectors communicate based on visible light communication (VLC).
3. The position tracking system of claim 1 , wherein each of the one or more beacon transmitters is a visible light transmitter, an infrared (IR) transmitter, or an ultraviolet (UV) transmitter.
4. The position tracking system of claim 1 , wherein each of the plurality of photodetectors is a light sensor, an IR sensor, a photodiode, or a beacon sensor.
5. The position tracking system of claim 1 , wherein processing the digital signals comprises performing high pass filtering, performing peak detection and binning, performing pulse duration binning, and looking up one or more beacon identification data.
6. The position tracking system of claim 1 comprises a remote server that is communicatively coupled to the one or more beacon receiver systems.
7. The position tracking system of claim 6 , wherein processing the digital signals comprises transmitting processed digital data to the remote server where location computation is performed by a processor of the remote server based at least in part on the processed digital data.
8. The position tracking system of claim 1 , wherein the field-of-view of the plurality of photodetectors increases with an elevation angle of the respective photodetector.
9. A position tracking system, comprising:
one or more location beacons;
one or more beacon receiver systems configured to be disposed on an object, and wherein each of the one or more beacon receiver systems comprises:
a motion sensor to collect motion data of the object;
a plurality of photodetectors configured to receive signals from the one or more location beacons;
an analog-to-digital convertor to convert analog signals received by the plurality of photodetectors to digital signals;
a memory;
a processor configured to execute instructions stored on the memory comprising instructions for receiving signals collected by the plurality of photodetectors; converting the received signals to digital signals; processing the digital signals; and computing a location of the object based on an analysis of combination of the digital signals and the motion data of the object, wherein the analog-to-digital converter, the memory, and the processor are on a single integrated circuit chip; and
wherein the one or more beacon receiver systems comprise a plurality of analog multiplexer integrated circuits configured to select and sample one photodetector from the plurality of photodetectors at a time.
10. The position tracking system of claim 9 , wherein each of the one or more location beacons is configured to emit modulated visible light.
11. The position tracking system of claim 9 , wherein each of the one or more location beacons is a light fixture.
12. The position tracking system of claim 9 , wherein the plurality of photodetectors comprises at least two different field-of-views.
13. The position tracking system of claim 9 , wherein a photodetector is integrated on the integrated circuit chip.
14. The position tracking system of claim 9 , wherein the one or more receiver systems are communicatively coupled to a remote server and location computation based at least in part of the processed digital signals is performed at the one or more beacon receiver systems or at the remote server.
15. The position tracking system of claim 9 , wherein the one or more beacon receiver systems are disposed on a moveable object with in a facility.
16. A method for providing location comprising:
providing one or more beacon transmitters;
receiving a signal from one or more beacon transmitters using a plurality of photodetectors disposed on one or more beacon receiver systems when one or more location beacons are within a field-of-view of the plurality of photodetectors, wherein the one or more beacon receiver systems are disposed on an object;
collecting motion data of the object;
converting the received signal to a digital signal;
processing the digital signal;
determining a beacon identification of the respective location beacon;
computing a location of the object based on the processed digital signal and motion data of the object;
displaying the computed location; and
wherein processing the digital signal comprises:
performing digital signal processing;
performing high pass filtering;
performing peak detection and binning; and
performing pulse duration binning.
17. The method of claim 16 , wherein computing the location is performed by a processor disposed on the object.
18. The method of claim 16 , wherein computing the location is performed by a processor at a remote server.
19. The method of claim 16 , wherein converting the received signal, processing the digital signal, and determining the beacon identification of the respective location are performed by a single integrated circuit chip.
20. The method of claim 16 , comprising decoding the processed signal.
21. The method of claim 20 , comprising: performing starting sequence detection and decoding.
22. The method of claim 16 , comprising performing error check.
23. The position tracking system of claim 1 , wherein the one or more beacon receiver systems comprise a plurality of analog multiplexer integrated circuits configured to select and sample one photodetector from the plurality of photodetectors at a time.
24. The position tracking system of claim 1 , wherein the one or more beacon receiver systems is switched from an off or idle state to an on state when the motion sensor detects motion of the object.
25. The position tracking system of claim 1 , wherein the plurality of photodetectors provide a collective field-of-view (FOV) that is larger than a FOV of the individual photodetector of the plurality of photodetectors.