The power budget feasibilities, the optical path losses, and the dispersion power penalties in the CWDM upstream wavelengths are precisely investigated in terms of related specifications required to enhance the network coverage to over 40 km with single-mode fibers (SMFs) based on ITU-T G.652.A and B and Corning's SMF-28e, as the worst-case and the practical-case feasibilities, respectively.
This makes it possible to use a thin photoabsorber layer, for enhance the collection efficiency, while maintaining the necessary length of optical path to prevent losses associated with incomplete light absorption.
The concept used in SENA is that current flows in the path of least resistance, which provides a simulation tool to evaluate the optical path with a minimum loss.
The power dynamic range an optical pre-amplifier as part of the upstream signal receivers needs to handle can be in range of up to 40 dB, because of the multi-wavelength channel operation and of the optical distribution network differential path loss.
We consider the effects of different optical pointing geometries and find that path loss is relatively insensitive to the Tx beam angle but increases considerably with increased Tx/Rx elevation angles and decreased Rx FOV for medium communication range.
To summarize energy losses in the optical path, 76% of the energy incident on the SLM is reflected, less than 40% of which passes the mask (the first diffractive order contains less than 20% of the light, but the mask also passes higher positive diffractive orders), and only 40% of light passing the mask is transmitted through the optics and objective to the sample.
This more efficient organization of the optical intensity leads to a far smaller path loss in MSD systems than in diffuse systems.
Blue is a shorter optical path difference (OPD) relative to red.
Secondly, due to changes in environmental conditions like the temperature and humidity, the optical path length of the delay loop may change leading to a loss of synchronization between the present drive frequency and the circulation frequency.
While for power coverage relying on the reflectivity of the ceiling and walls, a large path loss was observed due to the lack of a LOS optical path.
