PDL Localization and Estimation Through Linear Least Squares-Based Longitudinal Power Monitoring

An algorithm capable of localizing Polarization-Dependent Loss (PDL) and directly estimating its value in a multi-span optical transmission link using only Rx-side Digital Signal Processing (DSP) is presented. The algorithm employs a Linear Least Squares-based power profile estimation method and it succeeds in localizing multiple PDL sources along the link. Its performance is evaluated across diverse power levels, including SNR-maximizing ones, resulting in consistently comparable results

Longitudinal Power Monitoring Performance with Subcarrier Multiplexing Transmission

We investigate the performance of Longitudinal Power Monitoring (LPM) algorithms at the small symbol rates achieved with subcarrier multiplexing. We show that at those symbol rates LPM is still effective, albeit with a noisier estimation profile

Estimation Accuracy of Polarization State from Coherent Receivers for Sensing Applications

We experimentally investigate on the intrinsic accuracy in fiber State of Polarization estimation from the DSP of commercial coherent tranceivers, in terms of angular uncertainty on the Poincaré’s sphere vs. received OSNRs, for sensing applications. We then demonstrate how using a moving average enhances accuracy

Architectures and Key Technical Challenges for 5G Systems Incorporating Satellites

Satellite Communication systems are a promising solution to extend and complement terrestrial networks in un- served or under-served areas, as reflected by recent commercial and standardisation endeavours. In particular, 3GPP recently initiated a Study Item for New Radio (NR), i.e., 5G, Non-Terrestrial Networks aimed at deploying satellite systems either as a stand-alone solution or as an integration to terrestrial networks in mobile broadband and machine-type communication scenarios. However, typical satellite channel impairments, as large path losses, delays, and Doppler shifts, pose severe challenges to the realisation of a satellite-based NR network. In this paper, based on the architecture options currently being discussed in the standardisation fora, we discuss and assess the impact of the satellite channel characteristics on the physical and Medium Access Control layers, both in terms of transmitted waveforms and procedures for enhanced Mobile BroadBand (eMBB) and NarrowBand-Internet of Things (NB-IoT) applications. The proposed analysis shows that the main technical challenges are related to the PHY/MAC procedures, in particular Random Access (RA), Timing Advance (TA), and Hybrid Automatic Repeat reQuest (HARQ) and, depending on the considered service and architecture, different solutions are proposed