Design and Performance Analysis of Noise Equivalent Model for Optical Fiber Link
In optical communication system different types of noises may be introduced into the signal. The effect of noise and corresponding degradation in the signal quality is of great interest for the design of fiber-optic communication systems. In the present paper an electrical equivalent form of different important noises has been developed in order to investigate its effects on the efficiency of an optical fiber link. The basic components of an optical link are laser diodes, fiber, splices, and optical detector. In the proposed model the laser diode is represented as voltage source with internal resistance. Thermal noise in fiber, connectors, and splices is estimated by using an equivalent resistor. PIN photodetector is choosen for the proposed optical link and equivalent circuit model for the same is derived by carrier rate equations using RC circuit with current sources. The variation of noise current with the variation of frequency is shown.
KeywordsNoise in optical fiber link Thermal noise Shot noise Modal noise Electrical equivalent model
The author would like to thank the authorities of Birla Institute of Technology, Mesra and Off-campus Deoghar for all the supports provided and granting institute seed money scheme to carry out this work.
- 1.Moratzy, E., Ahmadi, V., Moravvej-Farshi, M.K.: An integrated equivalent circuit model for relative intensity noise and frequency noise spectrum of a multimode semiconductor laser. IEEE J. Quant. Electron 38(10), 1366–1371 (2002)Google Scholar
- 2.Morishita, A., Ohmi, T., Nishizawa, J.: Impedence characteristics of double-heterostructure laser diodes. Solid-State Electron 22, 951–962 (1979)Google Scholar
- 3.Katz, J., Margalit, S., Harder, C., Wilt, D., Yariv, A.: The intrinsic equivalent circuit of a laser diode. IEEE J. Quantum Electron QE-17, 4–7 (1981)Google Scholar
- 4.Harder, C., Katz, J., Margalit, S., Shacham, J., Yariv, A.: Noise equivalent circuit of semiconductor laser diode. IEEE J. Quantum Electron QE-18, 333–337 (1982)Google Scholar
- 5.McCumber, D.E.: Intensity fluctuation in the output of cw laser oscillator. Phys. Rev. 141, 306–322 (1966)Google Scholar
- 6.Haug, H.: Quantum mechanical rate equations for semiconductor lasers. Phys. Rev. 184, 338–348 (1969)Google Scholar
- 7.Joyce, W.B., Dixon, R.W.: Analytic approximation for the fermi energy of an ideal fermi gas. Appl. Phys. Lett. 31, 354–356 (1977)Google Scholar
- 8.John, M.: Optical Fiber Communications, 2nd edn. PHI (2005)Google Scholar
- 9.Arnold, H., Petermann, K.: Intrinsic noise of semiconductor lasers in optical communication systems. Opt. Quantum Electron 12, 207–219 (1980)Google Scholar
- 10.Chen, H., Liu, S.: PIN avalanche photodiodes model for circuit simulation. IEEE J. Quantum Electron 31, 2105–2109 (1996)Google Scholar