Optical Subcarrier Generation

1. Optical Subcarrier Generation Long Xiao 03/12/2003

2. Outline • Optical Subcarrier generate • Optical phase locked loop (OPLL)

3. Four Methods of Optical Generation of a Millimeter-wave subcarrier • Direct modulation of a laser diode. • External modulation. • Laser mode locking. • Heterodyning of two single-mode lasers.

4. A Tunable Millimeter-Wave Optical Transmitter

5. Photograph of Two Laser Module

6. Spectrum of the Heterodyne Signal The 0.3 nm wavelength separation between the outputs of two microchip-lasers corresponds to 90 GHz heterodyne signal.

7. Performance of the Heterodyne System • Continuous tuning range (CTR): 45 GHz. • Sensitivity: 13.4 MHz/ V. • Phase noise: -90 dBc/Hz at 10 kHz offset.

8. Diagram of the Optical Phase Locked Loop With Reference Signal Master Laser Optical Coupler Photodector Reference Signal Slave Laser Loop Filter

9. Diagram of the Phase Locked Loop With Delay Line

10. Packaged Optical Phase Locked Loop

11. References • [1] Y. LI, A. J. C. Vieira, S. M. Goldwasser, P. R. Herczfeld, “Rapidly Tunable Millimeter-Wave Optical Transmitter for Lidar/Radar”, IEEE Transactions on Microwave Theory and Techniques, special issue on microwave and millimeter-wave photonics, Vol. 49, No. 10, pp. 2048-2054, October 2001. • [2] Y. Li, S. Goldwasser, P. R. Herczfeld, “Optical Generated Dynamically Tunable,Low Noise Millimeter Wave Signals Using Microchip Solid Satte Lasers. • [3] Yao, X. Steve, et al, “Optoelectronic oscillator for photonic systems”, IEEE Journal of Quantum Electronics, v32, n7, pp 1141-1149, Jul, 1996. • [4] Yao, X. Steve, et al, “Multiloop optoelectronic oscillator”, IEEE Journal of Quantum Electronics, v36, n1, pp 79-84, 2000. • [5] R. T. Ramos, A. J. Seeds, “Delay, Linewidth and Bandwidth Limitations in Optical Phase-locked Loop Design”, Electronics Letters, Vol. 26, No. 6, pp 389-391, March 1990. • [6] A. C. Bordonalli, C. Walton, A. J. Seeds, ”High-Performance Homodyne Optical Injection Phase-Lock Loop Using Wide-Linewidth Semiconductor Lasers”, IEEE Photonics Technology Letters, Vol. 8, No. 9, September 1996.

12. References • [7] R. T. Ramos and A. J. Seeds, “comparison between first-order and second-order optical phase-lock loops”, IEEE microwave and guided wave letters, vol. 4, no. 1. January 1994. • [8] L. N. Langley, M. D. Elkin, C. Edge, M. J. Wale, U. Gliese, X. Huang, and A. J. Seeds, “packaged semiconductor laser optical phase-locked loop (OPLL) for Photonic generation, processing and transmission of microwave signals. IEEE Transcations on microwave theory and techniques, vol. 47, no. 7, July 1999. • [9] L. G. Kazovsky, and D. A. Atlas, “A 1320 nm experimental optical phase-locked loop”, IEEE Photonics technology letters, vol. 1. No. 11, November 1989. • [10] L. G. Kazovsky, and B. Jensen, “experimental relative frequency stabilization of a set of lasers using optical phase-locked loops”, IEEE Photonics technology letters, vol. 2. No. 7, July 1990. • [11] L. G. Kazovsky, and D. A. Atlas, “A 1320-nm experimental optical phase-locked loop: performance investigation and PSK homodyne experiments at 140 Mb/s and 2 Gb/s”. Journal of Lightwave technology, vol. 8. No. 9. September 1990.