Theoretical and experimental investigation of second-order atmospheric effects impairing W-band SatCom systems
Abstract
The operational frequency of modern satellite communication (SatCom) systems is gradually shifting to the spectrum portion above the traditional Ku band, mainly to take advantage of the larger bandwidth available, as well as to avoid channel congestion and interference issues. This is the case of satellites already operating in the Ka band and of Smart Gateways, foreseen to upload contents with carriers in the Q/V band. Recently, interest has also arisen in SatCom systems planned to operate even at higher frequencies, namely in the W band. As is well known, the main drawback to the use of higher frequencies comes from atmospheric constituents, namely gases, clouds and hydrometeors, which cause extinction of the radiated electromagnetic power. Detrimental effects increase significantly with frequency and, accordingly, the availability and Quality of Service (QoS) of SatCom systems become progressively more critical. As a result, significant research activities have been promoted so far for the in-depth investigation of such impairments to electromagnetic waves propagating in the atmosphere. Recently, the Alphasat satellite was selected by the Italian Space Agency (ASI) and the European Space Agency (ESA) to host a telecommunication payload implementing ACM (Adaptive Coding and Modulation) and a propagation payload consisting of two continuous-wave transmitters in the Ka (19.7 GHz, vertical polarization) and in the Q (39.4 GHz, 45° tilted linear polarization) bands. The main goals of the experiments are to investiagate the atmospheric impairments at high frequency and to verify the effectiveness of advanced techniques for the mitigation of detrimental atmospheric effects, known as Fade Mitigation Techniques (FMTs): ACM and site diversity are typical examples. Besides experiments, also theoretical research activities have been promoted, mainly to develop models for the prediction of propagation impairments, and for the simulation and performance evaluation of systems
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Apr 09, 2018
- Source ID
- FA95501710335
Entities
People
- Lorenzo Luini
Organizations
- Air Force Office of Scientific Research
- Polytechnic University of Milan
- United States Air Force