Parameters
Presets
Fiber Parameters
Core diameter d
8.2 μm
Core index n₁
1.4680
Cladding index n₂
1.4630
Wavelength λ
1310 nm
Propagation Parameters
Attenuation α
0.35 dB/km
Dispersion D
2.0 ps/(nm·km)
Spectral width Δλ
0.1 nm
Fiber length L
10.0 km
—
Numerical Aperture NA
—
V-number
—
Total Loss [dB]
—
Pulse Broadening [ps]
—
BDP [GHz·km]
—
Max Bit Rate [Gb/s]
Distance vs Loss / Pulse Broadening
Wavelength vs V-number
Key Formulas
Numerical Aperture:
$$\mathrm{NA} = \sqrt{n_1^2 - n_2^2}$$Normalized Frequency (V-number):
$$V = \frac{\pi d}{\lambda}\,\mathrm{NA}$$$V < 2.405$ → Single-mode | $V \geq 2.405$ → Multimode
Pulse Broadening:
$$\tau = D \cdot L \cdot \Delta\lambda$$Max Bit Rate (NRZ):
$$B_{\max} = \frac{0.7}{\tau}$$
Engineering Note: SMF-28 achieves zero dispersion at 1310 nm and minimum loss (~0.18 dB/km) at 1550 nm. Long-haul WDM systems operate at 1550 nm with EDFA amplification. The V-number is fundamental to waveguide coupler, AWG, and WDM device design.