OptiSystem Tutorials

Electrical PLL

The system demonstrates an electrical phase-locked loop. Sample: EPLL.osd The layout presented in the figure below is PLL system configured with a phase detector, a low pass filter and a voltage controlled oscillator. This example shows the response of a PLL to a sequence of pulses modulated in frequency to an electrical carrier at 1GHz.…

Analysis of Gain and Noise in Erbium doped fiber

This lesson demonstrates the performance of an amplifier (gain and noise) based on Giles and Desurvire [1] reference. Figure 1: Layout of the system considered in the analysis of gain and ASE The characteristics of noise and gain presented in Figure 4.b [1] are reproduced through the system shown in Figure 1. Figure 2 shows…

Optimizing the EDFA gain for WDM lightwave systems

In this tutorial, we provide an example of the gain flatness optimization type. The gain of the EDFA will be flattened by optimizing the fiber length and pump power. One difficulty in implementing a WDM system including EDFA’s is that the EDFA gain spectrum is wavelength dependent. This effect results in SNR differential between channels…

Excited state absorption impact on EDFA performance

This lesson shows the influence of signal excited-state absorption (ESA) on the performance of an EDFA. The effect of signal ESA happens because a signal photon is absorbed by an erbium ion in an excited state, thereby promoting it to an even higher energy state and causing degradation in the amplifier efficiency. This effect is…

Ion-ion interaction effects

This lesson demonstrates two of the ion-ion interaction effects on EDFAs: homogeneous upconversion effect (HUC) inhomogeneous pair-induced quenching (PIQ) As explained in the technical description, the ion-ion interaction effects relate to the issue of energy transfer between rare earth ions. When the local concentration of rare ions becomes high enough, it is no longer valid…

Rayleigh backscattering in EDFA

This lesson demonstrates the Rayleigh backscattering effect in the EDFA. The backscattering from an EDFA exceeds backscattering from an equivalent length of a non-doped fiber. Because Rayleigh backscattering can cause degradation in the EDFA performance [1], this effect has to be considered in the simulations to give better accuracy in the results. The EDF component…

Inhomogeneous broadening in EDFAs

This lesson demonstrates the inhomogeneous broadening in an erbium-doped fiber. In this lesson, the saturation regime in an EDFA is analyzed based on two approaches: homogeneous broadening. inhomogeneous broadening. For this purpose, the EDF component is set to the inhomogeneous model and simulations are done for different input signal powers. Figure 1 shows the system used in…

Power transients in EDFAs

This lesson demonstrates the transient effects in an EDFA caused by the addition or deletion of channels using the EDFA Dynamic models of the OptiSystem. The performance of a WDM system can be critically affected by the adding-dropping of WDM channels since all channels present are amplified simultaneously by each amplifier and share the available…

Temperature dependence in EDFA

This lesson demonstrates the temperature dependence in the absorption coefficient of an EDFA. The temperature dependence in an EDFA manifests through the variation in the absorption α and gain g* coefficients (or absorption σa and emission σe cross-sections) [1], [2]. Here, to demonstrate the effect of temperature dependence, simulations are done using different temperatures and…

Ytterbium-doped fiber amplifiers

The objective of this lesson is to demonstrate the performance of ytterbium-doped fiber amplifiers. First of all, the gain spectra are analyzed for the pump wavelength at 910 nm and with different input pump powers: 1mW, 10mW and 30mW. The system used in the simulation is shown in Figure 1. Figure 1: System layout for…