1. 16.711 Lecture 8 Optical Fiber Amplifier – noise and BER Last lecture Introduction to Fiber Optical Amplifier – types and applications Erbium-doped fiber amplifier (EDFA) External pumping and amplifier gain Power-conversion efficiency and gain profile

2. 16.711 Lecture 8 Optical Fiber Amplifier – noise and BER Today Amplifier Noise OSNR and BER System Applications

3. 16.711 Lecture 8 Optical Fiber Amplifier – noise and BER Einstein’s A and B coefficients is the distribution function. is number of optical modes at v.

4. 16.711 Lecture 8 Optical Fiber Amplifier – noise and BER Noise Power is the spontaneous factor.

5. 16.711 Lecture 8 Optical Fiber Amplifier – noise and BER Amplified spontaneous noise Noise Power spectral density: Total ASE power: Total power:

6. 16.711 Lecture 8 Optical Fiber Amplifier – noise and BER Receiver noise Total photo-detector current: Total ASE power: R is the resistance of the detector load resistor.

7. 16.711 Lecture 8 Optical Fiber Amplifier – noise and BER Receiver noise Total photo-detector current:

8. 16.711 Lecture 8 Optical Fiber Amplifier – noise and BER Gain and Noise Figure Total photo-detector current:

9. 16.711 Lecture 8 Optical Fiber Amplifier – noise and BER Amplifier System Noise figure (NF) Detector EDF Input Output Electronics External control 980 pump WDM 5%Tap

10. 16.711 Lecture 8 Optical Fiber Amplifier – noise and BER BER calculation: Quantum limit detection, Poisson’s equation: Gaussian Noise Statistics :

11. 16.711 Lecture 8 Optical Fiber Amplifier – noise and BER BER calculation: OSNR =10dB for 2.5GBit/s OSNR =15dB for 10GBit/s

12. 16.711 Lecture 8 Optical Fiber Amplifier – noise and BER PreAmp:

13. 16.711 Lecture 8 Optical Fiber Amplifier – noise and BER In-line Amp:

14. 16.711 Lecture 8 Optical Fiber Amplifier – noise and BER Amplifier Chain:

15. 16.711 Lecture 8 Optical Fiber Amplifier – noise and BER Amplifier Chain:

16. 16.711 Lecture 8 Optical Fiber Amplifier – noise and BER Amplifier Chain:

17. 16.711 Lecture 8 Optical Fiber Amplifier – noise and BER Amplifier Chain:

18. 16.711 Lecture 8 Optical Fiber Amplifier – noise and BER Amplifier Chain: