9 research outputs found
UAV-enabled optimal position selection for secure and precise wireless transmission
In this letter, two unmanned-aerial-vehicle (UAV) optimal position selection
schemes are proposed. Based on the proposed schemes, the optimal UAV
transmission positions for secure precise wireless transmission (SPWT) are
given, where the maximum secrecy rate (SR) can be achieved without artificial
noise (AN). In conventional SPWT schemes, the transmission location is not
considered which impacts the SR a lot. The proposed schemes find the optimal
transmission positions based on putting the eavesdropper at the null point.
Thus, the received confidential message energy at the eavesdropper is zero, and
the maximum SR achieves. Simulation results show that proposed schemes have
improved the SR performance significantly
DOA Estimation for Hybrid Massive MIMO Systems using Mixed-ADCs: Performance Loss and Energy Efficiency
Due to the power consumption and high circuit cost in antenna arrays, the
practical application of massive multipleinput multiple-output (MIMO) in the
sixth generation (6G) and future wireless networks is still challenging.
Employing lowresolution analog-to-digital converters (ADCs) and hybrid analog
and digital (HAD) structure is two low-cost choice with acceptable performance
loss. In this paper, the combination of the mixedADC architecture and HAD
structure employed at receiver is proposed for direction of arrival (DOA)
estimation, which will be applied to the beamforming tracking and alignment in
6G. By adopting the additive quantization noise model, the exact closedform
expression of the Cramer-Rao lower bound (CRLB) for the HAD architecture with
mixed-ADCs is derived. Moreover, the closed-form expression of the performance
loss factor is derived as a benchmark. In addition, to take power consumption
into account, energy efficiency is also investigated in our paper. The
numerical results reveal that the HAD structure with mixedADCs can
significantly reduce the power consumption and hardware cost. Furthermore, that
architecture is able to achieve a better trade-off between the performance loss
and the power consumption. Finally, adopting 2-4 bits of resolution may be a
good choice in practical massive MIMO systems.Comment: 11 pages, 7 figure
A Survey on Security and Privacy of 5G Technologies: Potential Solutions, Recent Advancements, and Future Directions
Security has become the primary concern in many telecommunications industries today as risks can have high consequences. Especially, as the core and enable technologies will be associated with 5G network, the confidential information will move at all layers in future wireless systems. Several incidents revealed that the hazard encountered by an infected wireless network, not only affects the security and privacy concerns, but also impedes the complex dynamics of the communications ecosystem. Consequently, the complexity and strength of security attacks have increased in the recent past making the detection or prevention of sabotage a global challenge. From the security and privacy perspectives, this paper presents a comprehensive detail on the core and enabling technologies, which are used to build the 5G security model; network softwarization security, PHY (Physical) layer security and 5G privacy concerns, among others. Additionally, the paper includes discussion on security monitoring and management of 5G networks. This paper also evaluates the related security measures and standards of core 5G technologies by resorting to different standardization bodies and provide a brief overview of 5G standardization security forces. Furthermore, the key projects of international significance, in line with the security concerns of 5G and beyond are also presented. Finally, a future directions and open challenges section has included to encourage future research.European CommissionNational Research Tomsk Polytechnic UniversityUpdate citation details during checkdate report - A
WFRFT-aided Power-efficient Multi-beam Directional Modulation Schemes Based on Frequency Diverse Array
The artificial noise (AN) aided multi-beam directional modulation (DM)
technology is capable of wireless physical layer secure (PLS) transmissions for
multiple desired receivers in free space. The application of AN, however, makes
it less power-efficient for such a DM system. To address this problem, the
weighted fractional Fourier transform (WFRFT) technology is employed in this
paper to achieve power-efficient multi-beam DM transmissions. Specifically, a
power-efficient multi-beam WFRFT-DM scheme with cooperative receivers and a
power-efficient multi-beam WFRFT-DM scheme with independent receivers are
proposed based on frequency diverse array (FDA), respectively. The bit error
rate (BER), secrecy rate, and robustness of the proposed multi-beam WFRFT-DM
schemes are analyzed. Simulations demonstrate that 1) the proposed multi-beam
WFRFT-DM schemes are more power-efficient than the conventional multi-beam
AN-DM scheme; 2) the transmission security can also be guaranteed even if the
eavesdroppers are located close to or the same as the desired receivers; and 3)
the proposed multi-beam WFRFT-DM schemes are capable of independent
transmissions for different desired receivers with different modulations.Comment: accepted by IEEE Transactions on Wireless Communications, 16 pages,
12 figure