1 research outputs found
A PHY Layer Security Analysis of a Hybrid High Throughput Satellite with an Optical Feeder Link
Hybrid terrestrial-satellite (HTS) communication systems have gained a
tremendous amount of interest recently due to the high demand for global high
data rates. Conventional satellite communications operate in the conventional
Ku (12 GHz) and Ka (26.5-40 GHz) radio-frequency bands for assessing the feeder
link, between the ground gateway and the satellite. Nevertheless, with the aim
to provide hundreds of Mbps of throughput per each user, free-space optical
(FSO) feeder links have been proposed to fulfill these high data rates
requirements. In this paper, we investigate the physical layer security
performance for a hybrid very high throughput satellite communication system
with an FSO feeder link. In particular, the satellite receives the incoming
optical wave from an appropriate optical ground station, carrying the data
symbols of users through various optical apertures and combines them using
the selection combining technique. Henceforth, the decoded and regenerated
information signals of the users are zero-forcing (ZF) precoded in order to
cancel the interbeam interference at the end-users. The communication is
performed under the presence of malicious eavesdroppers nodes at both hops.
Statistical properties of the signal-to-noise ratio of the legitimate and
wiretap links at each hop are derived, based on which the intercept probability
metric is evaluated. The derived results show that above a certain number of
optical apertures, the secrecy level is not improved further. Also, the
system's secrecy is improved using ZF precoding compared to the no-precoding
scenario for some specific nodes' positions. All the derived analytical
expressions are validated through Monte Carlo simulations.Comment: 17 pages, 10 figure