Multi-ring resonator implementation of optical spectrum reshaper for chirp managed laser technology

1. A fiber optic transmission system comprising:

an optical signal source adapted to produce a frequency modulated signal; and

a multi-ring resonator optical spectrum reshaper (OSR) adapted to convert the frequency modulated signal into a substantially amplitude modulated signal.

2. A fiber optic system according to claim 1 wherein the operating point of the frequency modulated signal is near the edge of the transmission peak of the multi-ring resonator.

3. A fiber optic system according to claim 1 wherein the frequency modulated source is a distributed feedback (DFB) laser.

4. A fiber optic system according to claim 3 wherein the DFB laser is integrated with the multi-ring resonator on the same substrate.

5. A fiber optic system according to claim 1 wherein the frequency modulated source is a DFB laser array.

6. A fiber optic transmission system comprising:

an optical signal source adapted to produce a frequency modulated signal; and

a multi-ring resonator optical spectrum reshaper (OSR) adapted to convert the frequency modulated signal into a substantially amplitude modulated signal,

wherein the multi-ring resonator OSR comprises coupled straight sections and ring waveguides.

7. A fiber optic system according to claim 6 wherein the number, the radii of the rings and the coupling between the rings is adjusted to produce a desired transmission profile.

8. A fiber optic system according to claim 7 wherein the transmission function is a periodic function with a periodicity equal to an integer multiple of 50 GHz.

9. A fiber optic system according to claim 7 wherein the transmission spectrum of the multi-ring resonator is substantially Gaussian near each transmission peak.

10. A fiber optic system according to claim 9 wherein the 3 dB bandwidth of the transmission spectrum is approximately 0.8 times to approximately 1.2 times the bit rate of operation.

11. A fiber optic system according to claim 9 wherein the peak slope of the transmission profile is approximately 2 dB/GHz to approximately 3 dB/GHz.

12. A fiber optic system according to claim 7 wherein the transmission spectrum of the multi-ring resonator is substantially flat-topped near each transmission peak.

13. A fiber optic system according to claim 12 wherein the slope of the transmission function is <0.2 dB/GHz near the transmission peak.

14. A fiber optic transmission system comprising:

an optical signal source adapted to produce a frequency modulated signal; and

a multi-ring resonator optical spectrum reshaper (OSR) adapted to convert the frequency modulated signal into a substantially amplitude modulated signal,

wherein the slope of the slope of the transmission of the multi-ring resonator, measured in dB, is approximately 0.36 dB/GHz 2 to approximately 0.6 dB/GHz 2 .

15. A fiber optic system according to claim 14 wherein the 3 dB bandwidth of the transmission approximately is 65% to approximately 90% of the bit rate.

16. A fiber optic transmission system comprising:

an optical signal source adapted to produce a frequency modulated signal; and

a multi-ring resonator optical spectrum reshaper (OSR) adapted to convert the frequency modulated signal into a substantially amplitude modulated signal,

further including a wavelength locking circuit adapted to wavelength lock the frequency modulated input signal to the multi-ring resonator by comparing the optical power of the input signals to the multi-ring resonator with the optical power of the transmitted signals from multi-ring resonator at the through port and then adjusting the optical signal source to keep the ratio of the input optical power and the transmitted optical power substantially constant.

17. A fiber optic system according to claim 16 further including a first tap at the input to the multi-ring resonator, a first photodiode to receive the output of the first tap, a second tap at the output through port of the multi-ring resonator, and a second photodiode to receive the output of the second tap.

18. A fiber optic system according to claim 17 wherein the first and second taps are integrated on the same substrate as the multi-ring resonator.

19. A fiber optic transmission system comprising:

an optical signal source adapted to produce a frequency modulated signal; and

a multi-ring resonator optical spectrum reshaper (OSR) adapted to convert the frequency modulated signal into a substantially amplitude modulated signal,

further including a wavelength locking circuit adapted to wavelength lock the frequency modulated input signal to the multi-ring resonator by comparing the optical power of the input signals to the multi-ring resonator with the optical power of the rejected signals from multi-ring resonator at the drop port and then adjusting the optical signal source to keep the ratio of the input optical power and the rejected optical power substantially constant.

20. A fiber optic system according to claim 19 further including a first tap at the input to the multi-ring resonator, a first photodiode to receive the output of the first tap, a second tap at the drop port of the multi-ring resonator, and a second photodiode to receive the output of the second tap.

21. A fiber optic system according to claim 20 wherein the first and second taps are integrated on the same substrate as the multi-ring resonator.

22. A method for transmitting an optical signal through a fiber comprising:

producing a frequency modulated signal;

passing the frequency modulated signal through a multi-ring resonator optical spectrum reshaper (OSR) so as to convert the frequency modulated signal into a substantially amplitude modulated signal; and

passing the substantially amplitude modulated signal into the fiber.