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asp net mvc barcode scanner Fiber Nonlinear Impairments in Software
Fiber Nonlinear Impairments Scanning Quick Response Code In None Using Barcode Control SDK for Software Control to generate, create, read, scan barcode image in Software applications. Painting QR In None Using Barcode printer for Software Control to generate, create QR Code 2d barcode image in Software applications. The phase shift is a function of time SPM (t) and knowing that frequency is the derivative of phase shift with respect to time, Eq (735) can be expressed as Eq (736) = d SPM dP = L dt dt eff QR Scanner In None Using Barcode decoder for Software Control to read, scan read, scan image in Software applications. Encode Quick Response Code In Visual C#.NET Using Barcode creator for Visual Studio .NET Control to generate, create QR Code 2d barcode image in VS .NET applications. (736) Denso QR Bar Code Maker In Visual Studio .NET Using Barcode printer for ASP.NET Control to generate, create QR Code image in ASP.NET applications. QRCode Drawer In Visual Studio .NET Using Barcode maker for Visual Studio .NET Control to generate, create QR Code image in .NET applications. where is the change in frequency caused by the change in phase shift at location L, s 1 Equation (736) shows the relationship between the change in signal power and frequency shift around the carrier frequency, see Fig 79 The reason for this is explained as follows As an optical pulse propagates in a fiber, the leading edge of the pulse s amplitude causes the refractive index of the fiber to increase, resulting in a shift to a lower frequency for the beginning of the pulse The falling edge of the pulse s amplitude causes the refractive index to decrease, resulting in Draw QR Code In VB.NET Using Barcode generator for Visual Studio .NET Control to generate, create QRCode image in .NET framework applications. Data Matrix Drawer In None Using Barcode generation for Software Control to generate, create ECC200 image in Software applications. Power (mW) GS1  12 Generator In None Using Barcode drawer for Software Control to generate, create UPC Code image in Software applications. Encoding Barcode In None Using Barcode creator for Software Control to generate, create bar code image in Software applications. 50 60 Time (ps) EAN / UCC  13 Drawer In None Using Barcode encoder for Software Control to generate, create EAN13 image in Software applications. Code128 Maker In None Using Barcode creator for Software Control to generate, create Code128 image in Software applications. Delta
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a shift to a higher frequency for the end of the pulse Over the pulse width, in the time domain, its frequency changes as shown in Fig 19a and b This is referred to as positive frequency chirp Since different optical frequencies travel at different speeds in a fiber, the pulse width expands or compresses Pulse width expansion leads to intersymbol interference and worst BER Refer to Chap 1 for more details on chirped pulse propagation The pulse s frequency change is a modulation caused by a phase shift induced by itself and therefore the effect is called selfphase modulation This effect caused by high optical power limits the maximum transmission rate possible in the fiber It should be noted that this wavelength chirping is not linear in time as the pulse propagates in the fiber, which is different from laser frequency chirping Solving the nonlinear Schr dinger equation [Eq (140)] using only the Kerr nonlinear term and with the Gaussian pulse Eq (145) where chirp C0 = 0, Cvijetic14 shows that the pulse width broadening factor due to SPM and chromatic dispersion can be estimated with Eq (737) A + z 1 A t + j 2 2 A 3 3 A + 2 t 2 6 t 3 CD effect CD slope
A 2 Attenua tion
= j A A
SPM 1/2 Group velocity
SPM 2 Leff L 2 4 L2 L2 2 eff 2 = 1 + + 1 + 4 2 2 o 2LNL o 3 3 LNL 4 o (737) Here the nonlinear length LNL term is introduced and is defined as the fiber length required to produce one radian of nonlinear phase rotation at power Po, see Eq (738) LNL = Aeff 2 n2 Po (738) The groupvelocity dispersion (GVD) parameter 2 is defined in Eq (417) and is shown below 2 = where 2 CD c 2 c SPM = signal RMS pulse width (Gaussian pulse shape) at location L, s o = signal RMS pulse width (Gaussian pulse shape) at the beginning of fiber, s SPM/ o = pulse width broadening factor due to SPM L = fiber link length, m LNL = fiber nonlinear length, m Leff = fiber effective length, m Po = pulse peak power at launch, W 2 = groupvelocity parameter, s2/m Fiber Nonlinear Impairments
= center wavelength of the optical signal, m CDc = chromatic dispersion coefficient, s/(m m) n2 = nonlinearindex coefficient which varies for different fibers between 20 10 20 to 35 10 20 m2/W, (typical is 30 10 20 m2/W) Aeff = fiber core s effective area, m2 Equation (737) shows that SPM effect is dependent on 1 Signal wavelength (the higher the wavelength the lesser the SPM) 2 Transmission rate, 10 Gbps (the higher the rate the greater the SPM effect) 3 Fiber core effective area (the larger the area the lesser the SPM) 4 Fiber dispersion (the lower the dispersion the lesser the SPM) 5 Fiber nonlinear index coefficient For transmission rates of 25 Gbps and less, SPM is not a limiting factor for NRZ and other OOK modulation formats The below discussion concentrates on NRZ modulated 10 Gbps and higher rates For 10 Gbps and higher transmission rates, we assume that optical signal pulses have a Gaussian shape as they propagate in a fiber A commonly used fit criteria for Gaussian pulses is that the pulse s RMS width needs to be less than 1/4 of the bit time slot T for at least 95% of the optical pulse power to fit within the time slot, see Eq (429) and Eq (739) o = 1 4R (739) where R = transmission rate, bps o = Gaussian pulse initial launch RMS width, s As a Gaussian pulse propagates in a fiber, it undergoes compression and expansion in the presence of SPM For example, assume a 10 Gbps signal with Gaussianshaped pulses is launched into a standard singlemode fiber (G652) Pulse width changes due to SPM occur as the signal propagates in the fiber as shown in Fig 710 When SPM is present, positive chirp occurs and the pulse initially undergoes compression, then expansion as it propagates further in the fiber This compression is helpful in extending the propagation limit for a distance up to ~100 km as shown in the example Comparing this effect to a pulse launched in a fiber with no SPM [Eq (160), C0 = 0], the pulse only expands as it propagates in the fiber Eventually, the SPM pulse width surpasses the nonSPM pulse width at ~100 km Therefore, in

