Optical signal generation with D/A converters and optical clock pulse stream

1. An apparatus comprising:

an optical train pulse generator for generating continuous optical pulses each having a narrow width;

a clock source having a high frequency for triggering the generator and operable as a sampling clock;

a digital-to-analog converter DAC for converting an input signal from a digital signal processor, the DAC responsive to the sampling clock;

a data modulator responsive to an amplified output from the DAC to modulate the continuous optical pulses from the train pulse generator; and

a filter for removing higher frequency harmonics from the modulated continuous optical pulses out of the data modulator.

2. The apparatus according to claim 1 , wherein the optical train pulse generator comprises a clock pulse intensity modulator responsive to an amplified clock signal for modulating a continuous wave light source.

3. The optical apparatus according to claim 2 , wherein the optical train pulse generator comprises a post processor for narrowing the pulse width of the optical pulse train from the clock intensity modulator.

4. The optical apparatus according to claim 3 , wherein the post processor comprises a Mach-Zhender interferometer.

5. The apparatus according to claim 1 , wherein the optical train pulse generator comprises a mode-locked laser which modulates a clock input, thereby generating optical pulses which are locked to the clock input.

6. The apparatus according to claim 5 , wherein the continuous optical pulses from the mode-locked laser are of a narrow enough pulse width sufficient for zero insertion.

7. The apparatus according claim 5 , wherein the continuous optical pulses from the mode-locked laser require post processing to attain a narrow enough pulse width sufficient for zero insertion.

8. The apparatus according to claim 5 , wherein the post processing comprises a Mach-Zhender interferometer.

9. A method comprising:

generating continuous optical pulses each having a narrow width;

triggering the generator with a clock source having a high frequency and operable as a sampling clock;

converting an input signal from a digital signal processor with a digital-to-analog converter DAC responsive to the sampling clock;

modulating the continuous optical pulses responsive to an amplified output from the DAC to provide modulated output pulses; and

removing higher frequency harmonics from the modulated optical pulses.

10. The method according to claim 9 , wherein the generating of the continuous optical pulses comprises modulating a continuous wave light source by a clock pulse intensity modulator responsive to an amplified clock signal for.

11. The method according to claim 10 , wherein the generating of the continuous optical pulses comprises narrowing the pulse width of the optical pulse train from the clock intensity modulator.

12. The method according to claim 11 , wherein the narrowing of the pulse width of the continuous optical pulses comprises a Mach-Zhender interferometer.

13. The method according to claim 9 , wherein the generating of the continuous optical pulses comprises modulating a clock input thereby generating continuous optical pulses which are locked to the clock input.

14. The method according to claim 13 , wherein the continuous optical pulses are of a narrow enough pulse width sufficient for zero insertion.

15. The method according to claim 13 , wherein the continuous optical pulses are further modified to attain a narrow enough pulse width sufficient for zero insertion.

16. The method according to claim 13 , wherein the further modified comprises applying an interferometer to the continuous optical pulses.