- 2 Gain dynamic model of the EDFA 64 2.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64 2.2 Erbium-doped fibre amplifier basics . . . . . . . . . . . . . . . . . . . . . 65 2.3 Gain dynamics model of single EDFA . . . . . . . . . . . . . . . . . . . . 71 2.4 EDFA dynamics model for OSNR investigation . . . . . . . . . . . . . . . 73 2.5 Properties of EDFAs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74 2.6 Pump configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84 2.7 Fibre lengths and geometries . . . . . . . . . . . . . . . . . . . . . . . . . 86 2.8 EDFA effects on the dynamic phenomena in optical networks . . . . . . . . 88 2.9 Numerical simulation techniques . . . . . . . . . . . . . . . . . . . . . . . 91 2.10 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93
- 4 Effect of Poisson traffic on EDFA transients 133 4.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133 4.2 Traffic types and models . . . . . . . . . . . . . . . . . . . . . . . . . . . 134 4.2.1 Poisson distribution traffic model . . . . . . . . . . . . . . . . . . 134 4.3 Impact of the Poisson traffic on the power transients of the EDFA . . . . . . 136 4.3.1 Simulation parameters . . . . . . . . . . . . . . . . . . . . . . . . 136 4.3.2 Results and analysis . . . . . . . . . . . . . . . . . . . . . . . . . 137 4.3.2.1 Power transient numerical analysis . . . . . . . . . . . . 138 4.3.2.2 Power transient statistical analysis . . . . . . . . . . . . 140 4.4 Power transients at small signal power . . . . . . . . . . . . . . . . . . . . 145 4.4.1 Simulation parameters . . . . . . . . . . . . . . . . . . . . . . . . 145 4.4.2 Results and analysis . . . . . . . . . . . . . . . . . . . . . . . . . 145 4.4.2.1 Numerical analysis of the power transients . . . . . . . . 146 4.4.2.2 Statistical analysis of power transients . . . . . . . . . . 148 4.5 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 155
- 6 Effect of power transients on optical receiver 196 6.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 196 6.2 Investigation of power and OSNR transients in cascades of EDFAs for optical networks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 197 6.2.1 Analysis of OSNR transients in EDFAs chain . . . . . . . . . . . . 199 6.2.2 Effect of power and OSNR transients of cascaded EDFAs on the optical receiver for WDM networks . . . . . . . . . . . . . . . . . 205 6.2.3 Effect of the abrupt input power on the power and OSNR transients in the EDFAs chain . . . . . . . . . . . . . . . . . . . . . . . . . . 207 6.3 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 209
- 7 Gain Locking System for EDFA in WDM Optical Networks 212 7.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 212 7.2 PID controller for the EDFA . . . . . . . . . . . . . . . . . . . . . . . . . 213 7.3 Simulation parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . 215 7.4 Numerical simulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 216 7.5 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 234
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