![Typical attenuation for low (left, ~3dB/km), medium (center, ~150dB/km) and high (~200dB/km) fog.](/fileadmin/_processed_/b/1/csm_free_space_468_237_0b325b477a.jpg)
Advantages
- Versus fiber: Fast and inexpensive link installation
- Versus radio: No wavelength regulation
Fields of applications
- Fast connectivity solutions (e.g. disaster recovery)
- 'Last-Mile' network solutions
- Microcell connectivity for mobile communication
- Mobile-network backhauling
Main challenges for FSO
- Pointing errors must be kept very low because of high antenna directivity
- Atmospheric perturbations (cloud, turbulence) must be mitigated
- Eye-safety conditions must be fulfilled