Secrecy Analysis on Network Coding in Bidirectional Multibeam Satellite Communications

• Network coding is an efficient means to improve the spectrum efficiency of satellite communications. However, its resilience to eavesdropping attacks is not well understood. This paper studies the confidentiality issue in a bidirectional satellite network consisting of two mobile users who want to exchange message via a multibeam satellite using the XOR network coding protocol. We aim to maximize the sum secrecy rate by designing the optimal beamforming vector along with optimizing the return and forward link time allocation. The problem is nonconvex, and we find its optimal solution using semidefinite programming together with a 1-D search. For comparison, we also solve the sum secrecy rate maximization problem for a conventional reference scheme without using network coding. Simulation results using realistic system parameters demonstrate that the bidirectional scheme using network coding provides considerably higher secrecy rate compared with that of the conventional scheme.

Subject headings

TEKNIK OCH TEKNOLOGIER  -- Elektroteknik och elektronik -- Signalbehandling (hsv//swe)

ENGINEERING AND TECHNOLOGY  -- Electrical Engineering, Electronic Engineering, Information Engineering -- Signal Processing (hsv//eng)

Keyword

mathematical programming;network coding;protocols;satellite communication;telecommunication security;1D search;XOR network coding protocol;bidirectional multibeam satellite communications;bidirectional satellite network;forward link time allocation;mobile user;optimal beamforming vector;return link time allocation;secrecy analysis;semidefinite programming;sum secrecy rate maximization problem;Array signal processing;Feeds;Network coding;Satellite broadcasting;Satellites;Security;Physical layer security;bidirectional satellite communications;network coding;secrecy rate;semidefinite programming

Publication and Content Type

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