4 research outputs found
Two High-Performance Amplitude Beamforming Schemes for Secure Precise Communication and Jamming with Phase Alignment
To severely weaken the eavesdropper's ability to intercept confidential
message (CM), a precise jamming (PJ) idea is proposed by making use of the
concept of secure precise wireless transmission (SPWT). Its basic idea is to
focus the transmit energy of artificial noise (AN) onto the neighborhood of
eavesdropper (Eve) by using random subcarrier selection (RSS), directional
modulation, phase alignment (PA), and amplitude beamforming (AB). By doing so,
Eve will be seriously interfered with AN. Here, the conventional joint
optimization of phase and amplitude is converted into two independent phase and
amplitude optimization problems. Considering PJ and SPWT require PA, the joint
optimization problem reduces to an amplitude optimization problem. Then, two
efficient AB schemes are proposed: leakage and maximizing receive
power(Max-RP). With existing equal AB (EAB) as a performance reference,
simulation results show that the proposed Max-RP and leakage AB methods perform
much better than conventional method in terms of both bit-error-rate (BER) and
secrecy rate (SR) at medium and high signal-to-noise ratio regions. The
performance difference between the two proposed leakage and Max-RP amplitude
beamformers is trivial. Additionally, we also find the fact that all three AB
schemes EA, Max-RP, and leakage can form two main peaks of AN and CM around Eve
and the desired receiver (Bob), respectively. This is what we call PJ and SPWT
Two Efficient Beamformers for Secure Precise Jamming and Communication with Phase Alignment
To achieve a better effect of interference on eavesdropper with an enhanced
security, a secure precise jamming (PJ) and communication (SPJC) is proposed
and its basic idea is to force the transmit energy of artificial noise (AN) and
confidential message into the neighborhoods of Eve and Bob by using random
subcarrier selection (RSS), directional modulation, and beamforming under phase
alignment (PA) constraint (PAC). Here, we propose two high-performance
beamforming schemes: minimum transmit power (Min-TP) and minimum regularized
transmit power (Min-RTP) to achieve SPJC under PAC and orthogonal constraint
(OC), where OC means that AN and CM are projected onto the null-spaces of the
desired and eavesdropping channels, respectively. Simulation results show that
the proposed Min-TP and Min-RTP methods perform much better than existing equal
amplitude (EA) method in terms of both bit-error-rate (BER) and secrecy rate
(SR) at medium and high signal-to-noise ratio regions. The SR performance
difference between the proposed two methods becomes trivial as the number of
transmit antennas approaches large-scale. More importantly, we also find the
fact that all three schemes including EA, Min-TP, and Min-RTP can form two main
peaks of AN and CM around Eve and Bob, respectively. This achieves both PJ and
secure precise wireless transmission (SPWT), called SPJC
Low-complexity and High-performance Receive Beamforming for Secure Directional Modulation Networks against an Eavesdropping-enabled Full-duplex Attacker
In this paper, we present a novel scenario for directional modulation (DM)
networks with a full-duplex (FD) malicious attacker (Mallory), where Mallory
can eavesdrop the confidential message from Alice to Bob and simultaneously
interfere Bob by sending a jamming signal. Considering that the jamming plus
noise at Bob is colored, an enhanced receive beamforming (RBF),
whitening-filter-based maximum ratio combining (MRC) (WFMRC), is proposed.
Subsequently, two RBFs of maximizing the secrecy rate (Max-SR) and minimum mean
square error (MMSE) are presented to show the same performance as WFMRC. To
reduce the computational complexity of conventional MMSE, a low-complexity MMSE
is also proposed. Eventually, to completely remove the jamming signal from
Mallory and transform the residual interference plus noise to a white one, a
new RBF, null-space projection (NSP) based maximizing WF receive power, called
NSP-based Max-WFRP, is also proposed. From simulation results, we find that the
proposed Max-SR, WFMRC, and low-complexity MMSE have the same SR performance as
conventional MMSE, and achieve the best performance while the proposed
NSP-based Max-WFRP performs better than MRC in the medium and high
signal-to-noise ratio regions. Due to its low-complexity,the proposed
low-complexity MMSE is very attractive. More important, the proposed methods
are robust to the change in malicious jamming power compared to conventional
MRC
Physical-Layer Security for Frequency Diverse Array Based Directional Modulation in Fluctuating Two-Ray Fading Channels
The frequency diverse array (FDA) based directional modulation (DM)
technology plays an important role in the implementation of the physical-layer
security (PLS) transmission of 5G and beyond communication system. In order to
meet the tremendous increase in mobile data traffic, a new design consuming
less memory for the FDA-DM-based PLS transmission is urgently demanded. In this
paper, an analytical symmetrical multi-carrier FDA model is proposed in three
dimensions, namely, range, azimuth angle, and elevation angle, which differs
from the conventional analytical approach with only range and azimuth angle
considered. Then, a single-point (SP) artificial noise (AN) aided FDA-DM scheme
is proposed, which reduces memory consumption of FDA-DM systems significantly
compared with the conventional zero-forcing (ZF) and singular value
decomposition (SVD) approaches. Moreover, the PLS performance of the proposed
low-memory-consumption FDA-DM scheme is analyzed in fluctuating two-ray (FTR)
fading channels for the first time, including bit error rate (BER), secrecy
rate (SR), and secrecy outage probability (SOP). More importantly, the
closed-form expressions for the lower bound of the average SR and the upper
bound of the SOP are derived, respectively. The effectiveness of the analytical
expressions is verified by numerical simulations. This work opens a way to
lower the memory requirements for the DM-based PLS transmission of 5G and
beyond communication system.Comment: 14 pages, 14 figures. arXiv admin note: text overlap with
arXiv:1908.0463