2 research outputs found
Physical layer security jamming: Theoretical limits and practical designs in wireless networks
Physical layer security has been recently recognized as a promising new design paradigm to provide security in wireless networks. In addition to the existing conventional cryptographic methods, physical layer security exploits the dynamics of fading channels to enhance secured wireless links. In this approach, jamming plays a key role by generating noise signals to confuse the potential eavesdroppers, and significantly improves quality and reliability of secure communications between legitimate terminals. This article presents theoretical limits and practical designs of jamming approaches for physical layer security. In particular, the theoretical limits explore the achievable secrecy rates of user cooperation based jamming whilst the centralized, and game theoretic based precoding techniques are reviewed for practical implementations. In addition, the emerging wireless energy harvesting techniques are exploited to harvest the required energy to transmit jamming signals. Future directions of these approaches, and the associated research challenges are also briefly outlined
Cucurbituril and Azide Cofunctionalized Graphene Oxide for Ultrasensitive Electro-Click Biosensing
To
achieve high selectivity and sensitivity simultaneously in an
electrochemical biosensing platform, cucurbituril and azide cofunctionalized
graphene oxide, a new functional nanomaterial that acts as a go-between
to connect the recognition element with amplified signal architecture,
is developed in this work. The cucurbituril and azide cofunctionalized
graphene oxide features a high specific surface area with abundant
levels of the two types of functional groups. Specifically, it emerges
as a powerful tool to link recognition elements with simplicity, high
yield, rapidity, and highly selective reactivity through azide-alkynyl
click chemistry. Moreover, it possesses many host molecules to interact
with guest molecules (also signal molecules)-grafted branched ethylene
imine polymer, through which the detection sensitivity can be greatly
improved. Together with electro-click technology, a highly controllable,
selective, and sensitive biosensing platform can be easily created.
For VEGF<sub>165</sub> protein detection, the electro-click assay
has high selectivity and sensitivity; a dynamic detection range from
10 fg mL<sup>–1</sup> to 1 ng mL<sup>–1</sup> with a
detection limit of 8 fg mL<sup>–1</sup> was achieved. The electro-click
biosensing strategy based on cucurbituril and azide cofunctionalized
graphene oxide would have great promise for other target analytes
with a broad range of applications