A new approach to design digitally tunable optical filter system for DWDM (Dense Wavelength Division Multiplexed) optical networks is presented. This digitally tunable optical filter system uses semiconductor optical amplifiers (SOAs) and DWDM thin film filter based wavelength selection elements. The design is very easy to configure, expand and reduce. This digitally tunable optical filter system is smaller in size, lesser in weight, cheaper in costt, consumes low power and has better timing performance as compared to digitally tunable optical filter suggested by researchers recently.
2. Wooten, E. L., R. L. Stone, E. W. Miles, and E. M. Bradely, "Rapidly tunable narrowband wavelength filter using LiNbO3 unbalanced Mach-Zehnder interferometers," J. Lightwave Tech., Vol. 14, 2530-2536, 1996.
3. Oda, K., N. Yakato, T. Kominato, and H. Toba, "A 16-channel frequency selection switch for optical FDM distribution systems," IEEE J. Sel. Areas Commun., Vol. 8, 1132-1140, 1990.
4. Stone, J. and L. W. Stulz, "High-performance fiber Fabry-Perot filters," Electron. Lett., Vol. 27, 2239-2240, 1991.
5. Born, M. and E.Wolf, Principles of Optics, 6th Ed., Pergamon, New york, 1980.
6. Zirngibl, M., C. H. Joyner, and B. Glance, "Digitally tunable channel dropping filter/equalizer based on wave guide grating router and optical amplifier integration," IEEE Photonics Tech. Lett., Vol. 6, 513-515, 1994.
7. Ishida, O., H. Takahashi, and Y. Inoue, "Digitally tunable optical filters using arrayed wave guide grating (AWG) multiplexers and optical switches," J. Lightwave Tech., Vol. 15, 321-327, 1997.
8. Sneh, A. and K. M. Johnson, "High-speed tunable liquid crystal filter for WDM networks," J. Lightwave Tech., Vol. 14, 1067-1080, 1996.
9. Chen, P. L., K. C. Lin, W. C. Chuang, Y. C. Tzeng, K. Y. Lee, and W. Y. Lee, "Analysis of a liquid crystal Fabry-Perot etalon filter: A novel model," IEEE Photonics Tech. Lett., Vol. 9, 467-469, 1997.
10. Fujii, Y., "High-isolation polarization-independent optical circulator coupled with single-mode fibers," J. Lightwave Tech., Vol. 9, 456-460, 1991.
11. Smith, D. A., J. E. Baran, J. J. Johnson, and K. W. Cheung, "Integrated-optic acoustically tunable filters for WDM networks," IEEE J. Sel. Areas Commun., Vol. 8, 1151-1159, 1990.
12. Kim, C.-S., F. N. Farokhrooz, and J. U. Kang, "Electro-optic wavelength-tunable fiber ring laser based on cascaded composite Sagnac loop filters," Opt. Lett., Vol. 29, 1677-1679, 2004.
13. Li, X., J. Chen, G. Wu, and A. Ye, "Digitally tunable optical filter based on DWDM thin film filters and semiconductor optical amplifiers," Opt. Express, Vol. 13, 1346-1350, 2005.
14. Banerjee, A., "New approach to design digitally tunable optical filter system for wavelength selective switching based optical networks," Progress In Electromagnetic Research Letters, Vol. 9, 93-100, 2009.