The conceptualisation of the sixth generation of mobile wireless networks (6G) has already started with some potential disruptive technologies resonating as enablers for driving the emergence of a number of innovative applications. Particularly, 6G will be a prominent supporter for the evolution towards a truly Intelligent Transportation System and the realization of the Smart City concept by fulfilling the limitations of 5G, once vehicular networks are becoming highly dynamic and complex with stringent requirements on ultra-low latency, high reliability, and massive connections. More importantly, providing security and privacy to such critical systems should be a top priority as vulnerabilities can be catastrophic, thus there are huge concerns regarding data collected from sensors, people and their habits. In this paper, we provide a timely deliberation of the role that promissory 6G enabling technologies such as artificial intelligence, network softwarisation, network slicing, blockchain, edge computing, intelligent reflecting surfaces, backscatter communications, terahertz links, visible light communications, physical layer authentication, and cell-free massive multiple-input multiple-output (MIMO) will play on providing the expected level of security and privacy for the Internet of Vehicles.

The flexibility and reconfigurability at the radio frequency (RF) front-end offered by the fluid antenna system (FAS) make this technology promising for providing remarkable diversity gains in networks with small and constrained devices. Toward this direction, this letter compares the outage probability (OP) performance of non-diversity and diversity FAS receivers undergoing spatially correlated Nakagami-m fading channels. Although the system properties of FAS incur in complex analysis, we derive a simple yet accurate closed-form approximation by relying on a novel asymptotic matching method for the OP of a maximum-gain combining-FAS (MGC-FAS). The approximation is performed in two stages, the approximation of the cumulative density function (CDF) of each MGC-FAS branch, and then the approximation of the end-to-end CDF of the MGC-FAS scheme. With these results, closed-form expressions for the OP and the asymptotic OP are derived. Finally, numerical results validate our approximation of the MGC-FAS scheme and demonstrate its accuracy under different diversity FAS scenarios.

By recognizing the tremendous flexibility of the emerging fluid antenna system (FAS), which allows dynamic reconfigurability of the location of the antenna within a given space, this paper investigates the performance of a single-antenna FAS over spatially correlated Nakagami-m fading channels. Specifically, simple and highly accurate closed-form approximations for the cumulative density function of the FAS channel and the outage probability of the proposed system are obtained by employing a novel asymptotic matching method, which is an improved version of the well-known moment matching. With this method, the outage probability can be computed simply without incurring complex multi-fold integrals, thus requiring negligible computational effort. Finally, the accuracy of the proposed approximations is validated, and it is shown that the FAS can meet or even exceed the performance attained by the conventional maximal ratio combining (MRC) technique.

The () performance of a wireless communication link through a () with phase errors is analyzed. Leveraging recent results that express the -based composite channel as an equivalent scalar fading channel, we show that the eavesdropper’s link is Rayleigh distributed and independent of the legitimate link. The different scaling laws of the legitimate and eavesdroppers signal-to-noise ratios with the number of reflecting elements, and the reasonably good performance even in the case of coarse phase quantization, show the great potential of -aided communications to enhance in practical wireless set-ups.

The fluid antenna system (FAS) has emerged as a disruptive technology that promises outstanding diversity and multiplexing gains comparable to or better than multiple-input multiple-output (MIMO), but without the issues of channel state information (CSI) acquisition and the advantage of requiring smaller physical spaces of upcoming user devices. This work investigates the potentialities of this technology to provide secure transmissions by analysing the secrecy outage probability (SOP) of two different implementations of FAS undergoing spatial correlated Nakagami- $m$ fading by assuming $i)$ non-diversity FAS and maximum-gain combining-FAS (MGC-FAS) diversity scheme at the legitimate node and $ii)$ multiple-antennas performing maximal ratio combining (MRC) at the eavesdropper. Specifically, using a novel asymptotic matching method, a simple and accurate closed-form approximations to the end-to-end signal-to-noise-ratio (SNR) distributions are derived in terms of well-known functions without incurring tricky functions or multi-fold integrals. Our findings reveal that the secrecy performance of the MGC-FAS beats the non-diversity FAS counterpart only when $i)$ the antenna size of the FAS tube is large enough, and $ii)$ the average SNR of the legitimate path is much greater than that of the eavesdropper link. Finally, numerical results validate our approximations of the SOP for the MGC-FAS scheme and demonstrate its accuracy under different FAS conditions.