6,291 research outputs found
Secure Communication with a Wireless-Powered Friendly Jammer
In this paper, we propose to use a wireless-powered friendly jammer to enable
secure communication between a source node and destination node, in the
presence of an eavesdropper. We consider a two-phase communication protocol
with fixed-rate transmission. In the first phase, wireless power transfer is
conducted from the source to the jammer. In the second phase, the source
transmits the information-bearing signal under the protection of a jamming
signal sent by the jammer using the harvested energy in the first phase. We
analytically characterize the long-time behavior of the proposed protocol and
derive a closed-form expression for the throughput. We further optimize the
rate parameters for maximizing the throughput subject to a secrecy outage
probability constraint. Our analytical results show that the throughput
performance differs significantly between the single-antenna jammer case and
the multi-antenna jammer case. For instance, as the source transmit power
increases, the throughput quickly reaches an upper bound with single-antenna
jammer, while the throughput grows unbounded with multi-antenna jammer. Our
numerical results also validate the derived analytical results.Comment: accepted for publication in IEEE Transactions on Wireless
Communication
Jamming Games in the MIMO Wiretap Channel With an Active Eavesdropper
This paper investigates reliable and covert transmission strategies in a
multiple-input multiple-output (MIMO) wiretap channel with a transmitter,
receiver and an adversarial wiretapper, each equipped with multiple antennas.
In a departure from existing work, the wiretapper possesses a novel capability
to act either as a passive eavesdropper or as an active jammer, under a
half-duplex constraint. The transmitter therefore faces a choice between
allocating all of its power for data, or broadcasting artificial interference
along with the information signal in an attempt to jam the eavesdropper
(assuming its instantaneous channel state is unknown). To examine the resulting
trade-offs for the legitimate transmitter and the adversary, we model their
interactions as a two-person zero-sum game with the ergodic MIMO secrecy rate
as the payoff function. We first examine conditions for the existence of
pure-strategy Nash equilibria (NE) and the structure of mixed-strategy NE for
the strategic form of the game.We then derive equilibrium strategies for the
extensive form of the game where players move sequentially under scenarios of
perfect and imperfect information. Finally, numerical simulations are presented
to examine the equilibrium outcomes of the various scenarios considered.Comment: 27 pages, 8 figures. To appear, IEEE Transactions on Signal
Processin
Physical Layer Security in Wireless Ad Hoc Networks Under A Hybrid Full-/Half-Duplex Receiver Deployment Strategy
This paper studies physical layer security in a wireless ad hoc network with
numerous legitimate transmitter-receiver pairs and eavesdroppers. A hybrid
full-/half-duplex receiver deployment strategy is proposed to secure legitimate
transmissions, by letting a fraction of legitimate receivers work in the
full-duplex (FD) mode sending jamming signals to confuse eavesdroppers upon
their information receptions, and letting the other receivers work in the
half-duplex mode just receiving their desired signals. The objective of this
paper is to choose properly the fraction of FD receivers for achieving the
optimal network security performance. Both accurate expressions and tractable
approximations for the connection outage probability and the secrecy outage
probability of an arbitrary legitimate link are derived, based on which the
area secure link number, network-wide secrecy throughput and network-wide
secrecy energy efficiency are optimized respectively. Various insights into the
optimal fraction are further developed and its closed-form expressions are also
derived under perfect self-interference cancellation or in a dense network. It
is concluded that the fraction of FD receivers triggers a non-trivial trade-off
between reliability and secrecy, and the proposed strategy can significantly
enhance the network security performance.Comment: Journal paper, double-column 12 pages, 9 figures, accepted by IEEE
Transactions on Wireless Communications, 201
- …