Secure Multi-Beam Satellite Systems using Adaptive Beamforming for 6G Communications

Abstract

The 6G network will be a fully connected world that integrates terrestrial wireless and satel lite communications. With the increasing utility and demand, the need for security increases in satellite communication. The users of this mode of communication along with all sorts of benefits in terms of Quality of Service (QoS) and reduced cost of services also demand confidentiality and integrity of their data. Eavesdropping is a major problem especially for those who send sensitive information through a satellite connection and in satellite networks, these tasks are significantly easier due to the broadcast nature of satellites versus fixed ter restrial. In the open space, the signal is spreading and The information might reach not just the authorized user, but also the nearby eavesdropper(illegal user) could obtain wireless power and retrieve secured information from the power leakage in signals. So, we pro posed adaptive beamforming algorithm, it is a signal processing procedure will generate the amplitude and phase in order to guide the tunable element of a holographic array of an tenna can be steered to transmit radio signals in a specific direction. The system consisted of an Direction-of-Arrival estimator (MUSIC and Min-Norm) for estimating the location of desired location/earth station, an adaptive beamformer for suppressing eavesdropper and enhancing the earth station beam transmitting signal information. In this thesis, comparison and performance evaluation of these adaptive algorithms i.e LMS and RLS for holographic antenna array in terms of secrecy capacity, speed present. The simulation results shows that, In both DoA algorithm have high-resolution and high-accuracy method, but Min-Norm unsuccessful to suppress the incorrect peaks(affect accuracy), MUSIC have drawback in to estimate the DOAs of more correlated signals(affect resolution). So that, in highly corre lated environment Min-Norm perform well but on the other environment MUSIC algorithm better. LMS-beamforming algorithm for increasing number of array elements, has better performance characteristics than RLS-algorithm because of their ability in placing deep null(Lower leakage power) towards the eavesdropper and producing much stronger beam towards the earth station as well as low-side-lobe-levels and increase in secrecy capacity. It is seen that the LMS algorithm has better secrecy capacity performance except that it has a very slow speed than RLS( 7.5 sec).