System and method of optical data communication with multiple simultaneous emitters and receivers

• US 20040234268A1
• Filed: 05/22/2003
• Published: 11/25/2004
• Est. Priority Date: 05/22/2003
• Status: Active Grant

• Current Assignee: Disney Enterprises Incorporated (The Walt Disney Company)
• Original Assignee: Disney Enterprises Incorporated (The Walt Disney Company)
• Inventors: Olch, Ronald Howard
• Granted Patent: US 7,009,501 B2
• Time in Patent Office: Days
• US Class Current: 398/118
• CPC Class Codes: H04B 10/1149 Arrangements for indoor wireless networking of information

Abstract

The system and method of the present invention optically transmits redundant packets of data using infrared signals at pseudo-random intervals to allow a receiver to distinguish between multiple simultaneous sources. The emitters repeatedly transmit a short packet at randomized intervals much shorter than the frame rate. Statistical analysis shows that the probability of collision of the desired packet with a packet from some other source is sufficiently low such that timely reception of at least one uncorrupted packet in the required time frame is assured.

Claims

1. A method of optical communication of data from a first object to a second object out of a plurality of objects, the method comprising the steps of:

providing a wireless emitter at the first object;

providing a wireless receiver at the second object;

determining a time limit by which a data packet must be successfully transmitted from the first object to the second object;

repeatedly transmitting the data packet at random intervals from the wireless emitter;

reading each data packet received at the receiver;

rejecting data packets that have been corrupted; and

analyzing data packets to see if they are intended for that receiver.

2. The method of claim 1 wherein the first and second objects are moving.

3. The method of claim 1 wherein the wireless emitter and wireless receiver utilize infrared signals.

4. The method of claim 1 wherein the object is a vehicle.

5. The method of claim 1 wherein the first object is leading the second object on a track or lane.

6. The method of claim 4 wherein each vehicle has a tachometer, and the velocity of each vehicle is periodically read from the tachometer.

7. The method of claim 6 wherein the data transmitted comprises the vehicle'"'"'s velocity and position.

8. The method of claim 1 wherein one or more objects other than the second object are also receiving data transmitted from the first object.

9. The method of claim 7 wherein said step of analyzing data packets to see if they are intended for that receiver comprises reading the vehicle position and accepting data if it is in close proximity to the receiving vehicle.

10. A method of optical communication of data from a first object to a second object out of a plurality of objects, the method comprising the steps of:

providing each of the plurality of objects with an optical emitter and an optical receiver for transmitting and receiving optical signals;

determining a time limit by which a data packet must be successfully transmitted from the first object to the second object;

repeatedly transmitting the data packet at random intervals much shorter than the frame rate from the emitter of the first object;

receiving data at the optical receiver of the second object; and

checking each data packet received at the receiver of the second object to determine if has been corrupted and accepting only those packets that have not been corrupted.

11. The method of claim 10 further comprising the step of analyzing the accepted data packets to see if the data packet is intended for that object.

12. The method of claim 11 wherein each object has an address, and the data packets include an address indicating which object the data packet is intended for.

13. The method of claim 11 wherein the receiver determines whether the data packet is intended for that object based on location information.

14. The method of claim 10 wherein the first and second objects are moving.

15. The method of claim 10 wherein the wireless emitter and wireless receiver utilize infrared signals.

16. The method of claim 10 wherein the object is a vehicle.

17. The method of claim 10 wherein the first object is leading the second object on a track or lane.

18. The method of claim 16 wherein each vehicle has a tachometer, and the velocity of each vehicle is periodically read from the tachometer.

19. The method of claim 18 wherein the data transmitted comprises the vehicle'"'"'s velocity and position.

20. The method of claim 10 wherein one or more other objects besides the second object are receiving data from the first object.

21. A method of detecting and preventing vehicle collision between at least two vehicles, one vehicle being a leading vehicle, and another being the trailing vehicle, the method comprising the steps of:

providing an infrared emitter at the rear of the leading vehicle so as to communicate data to at least the trailing vehicle behind it;

providing an infrared receiver at the front of a trailing vehicle so as to receive data from at least the leading vehicle;

providing radio frequency emitters in close proximity to the vehicles that transmit data about vehicle'"'"'s position;

providing an on-board computer for regularly gathering the vehicle'"'"'s velocity and vehicle'"'"'s position;

transmitting velocity and position data from the infrared emitter of the leading vehicle;

receiving data at the receiver of the trailing vehicle;

calculating, at the trailing vehicle, the distance from the leading vehicle to the trailing vehicle; and

predicting whether a collision will occur based on the distance calculated and the current velocity of the trailing vehicle.

22. The method of claim 21 further including the step of regulating the velocity of the vehicle so as to avoid a collision.

23. The method of claim 21 further including the step of providing a warning to the driver that a collision will occur.

24. A method of optical communication of data from one object to another, the method comprising the steps of:

providing each of the objects with a wireless emitter and a wireless receiver;

determining a time limit by which a data packet must be successfully transmitted;

repeatedly transmitting the data packet at random intervals from the wireless emitter;

reading each data packet received at the receiver;

rejecting data packets that have been corrupted; and

analyzing data packets to see if they are intended for that receiver.

25. The method of claim 24 wherein the step of analyzing whether a data packet is intended for that receiver is based on timeliness.

26. The method of claim 24 wherein the step of analyzing whether a data packet is intended for that receiver is based on applicability.