Generating of high rate modulated pulse streams

• US 20040208628A1
• Filed: 05/14/2004
• Published: 10/21/2004
• Est. Priority Date: 08/22/2002
• Status: Active Grant

• Current Assignee: Main Street Ventures, LLC
• Original Assignee: Main Street Ventures, LLC
• Inventors: Shahar, Arie, Halberthal, Eldan
• Granted Patent: US 7,362,976 B2
• Time in Patent Office: Days
• US Class Current: 398/161
• CPC Class Codes: H04J 14/08 Time-division multiplex systems

Abstract

The present invention provides an all optical system for generating high rate modulated signals including: a generator for generating a first periodic signal at a first rate; an optical chopping device arranged to receive the first periodic signal for producing a second periodic signal having pulses that are narrower than the pulses of the first signal; a splitting device for receiving and splitting the second periodic signal into multiple images of the second periodic signal propagating along multiple optical paths, the multiple optical paths including optical modulators for modulating the images of the second periodic signal at a first rate to produce modulated signals; an interleaving device for receiving and interleaving the modulated signals to produce a stream of modulated signal having a second ratewhich is higher than the first rate. In another version the present invention provides an optical rate increasing device, and in yet another version the present invention provides a system for interleaving multiple information channels into a high rate data stream.

Claims

1. An all optical system for generating high rate modulated signals comprising:

a generator for generating a first periodic signal at a first rate;

a rate increasing device arranged to receive said first periodic signal and to produce a second periodic signal at a second rate higher than said first rate;

a splitting device to receive and split said second periodic signal into multiple images of said second periodic signal propagating along multiple optical paths, said multiple optical paths including optical modulators to modulate said images of said second periodic signal at said second rate to produce modulated signals; and

an interleaving device to receiving and interleave said modulated signals to produce a stream of modulated signal having a third rate higher than said second rate.

2. The system of claim 1 wherein said first periodic signal has a duty cycle of less than 50%.

3. The system of claim 1 wherein said third rate is equal to an integer number of times said first rate.

4. The system of claim 1 wherein said generator is a mode locked laser.

5. The system of claim 1 wherein said rate increasing device includes splitters combiners and optical delay lines.

6. The system of claim 1 wherein said rate increasing device includes an optical loop containing a gate and an optical amplifier.

7. The system of claim 1 wherein said multiple optical paths include optical delay lines.

8. The system of claim 1 wherein said system further includes an optical amplifier to compensate for the splitting loss of said splitter.

9. The system of claim 1 wherein said system further includes a control unit to control said optical modulators.

10. The system of claim 9 wherein said system further includes a tapping device for providing a tapped signal from said first signal to said control unit.

11. The system of claim 1 wherein said optical modulators are arranged to operate at said second rate.

12. The system of claim 1 wherein said splitting device is a demultiplexer.

13. The system of claim 1 wherein said interleaving device is a multiplexer.

14. An all optical system for generating high rate modulated signals comprising:

a generator for generating a first periodic signal at a first rate;

an optical chopping device arranged to receive said first periodic signal and to produce a second periodic signal having pulses that are narrower than the pulses of said first signal;

a splitting device for receiving and splitting said second periodic signal into multiple images of said second periodic signal propagating along multiple optical paths, said multiple optical paths including optical modulators for modulating said images of said second periodic signal at said first rate to produce modulated signals;

an interleaving device for receiving and interleaving said modulated signals to produce a stream of modulated signal having a second ratehigher than said first rate.

15. The system of claim 14 wherein said generator includes an optical modulator.

16. The system of claim 15 wherein said modulator is arranged to operate at said first rate.

17. The system of claim 14 wherein said second rate is an integral number of said first rate.

18. The system of claim 14 wherein said multiple optical paths include optical delay lines.

19. The system of claim 14 wherein said system further includes an optical amplifier.

20. The system of claim 14 wherein said system further includes a control unit to control said optical modulators.

21. The system of claim 20 wherein said system further includes a tapping device for providing a tapped signal from said first signal to said control unit.

22. The system of claim 14 wherein said optical modulators are arranged to operate at said first rate.

23. The system of claim 14 wherein said splitting device is a demultiplexer.

24. The system of claim 14 wherein said interleaving device is a multiplexer.

25. An optical rate increasing device comprising:

an optical loop including an optical amplifier and a gate and having a first and a second terminals, said optical loop arranged to receive a first periodic signal from said first terminal and to produce at said second terminal a second periodic signal,

wherein the rate of said second periodic signal is higher than the rate of said first periodic signal.

26. The device of claim 25 wherein said rate of said second signal is an integral number of the rate of said first signal.

27. The device of claim 25 wherein said second rate is adjustable.

28. The device of claim 25 wherein said optical loop further includes a variable delay line.

29. The device of claim 25 wherein said gate is arranged to change its state from a transmitting state to a blocking state between every two consecutive pulses of said first signal.

30. An all optical system for interleaving the signals of multiple information channels comprising:

multiple optical chopping devices arranged along multiple optical paths to receive and chop the pulses of a first group of information channels and to produce a second group of information channels having pulses that are narrower than the pulses of said first group of information channels; and

an interleaving device to receive and interleave said second group of signals from said multiple optical paths to produce an information channel operating at a rate that is higher that the rate of each of said information channels of said first group.

31. The system of claim 30 wherein said optical paths include optical delay lines.

32. The system of claim 31 wherein said optical delay lines are variable optical delay lines.

33. The system of claim 32 wherein said system further includes a control unit for controlling said variable optical delay lines.