Related papers: Fundamental limitations for antenna radiation effi…
Enormous fluid antenna systems (E-FAS) have recently emerged as a new wireless architecture in which intelligent metasurfaces act as guided electromagnetic interfaces, enabling surface-wave (SW) propagation with much lower attenuation and…
In this paper, we consider capacities of single-antenna terminals communicating to large antenna arrays that are deployed on surfaces. That is, the entire surface is used as an intelligent receiving antenna array. Under the condition that…
Bounds on the frequency domain behavior of electrically small antennas are adapted to assess the time domain distortion or fidelity achievable by simple linear time-invariant (LTI) systems. Rigorous expressions for a TM$_{01}$ spherical…
Terahertz technology has made significant advances in the fields of spectroscopy, imaging and, more recently, wireless communications. In the latter, the use of this frequency band between 0.1 and 10 THz becomes extremely attractive due to…
The spectral efficiency of wireless networks can be made nearly infinitely large by deploying many antennas, but the deployment of very many antennas requires new topologies beyond the compact and discrete antenna arrays used by…
In this work, a novel design of electromagnetically reconfigurable antennas (ERAs) based on a fluid antenna system (FAS) is proposed, and the corresponding wireless channel model is established. Different from conventional antenna arrays…
We today live in the era of dynamic and mobile wireless enabled platforms. This kind of stringent communication capability in the face of volatile and turbulent mobility demands a fresh look at physical layer in general and antenna design…
The classical scenario where a \emph{single plane-wave} field impinge a Dallenbach absorber is well studied both theoretically and experimentally. However, occasionally a \emph{spectrum of plane-waves} impinges the absorber. Such a scenario…
Antennas, i.e., elements transforming localized or waveguide modes into freely propagating fields and vice versa, are vital components for wireless technologies across the entire spectrum of electromagnetic waves, including microwaves and…
The performance of broadband millimeter-wave (mmWave) RF architectures, is generally determined by mathematical concepts such as the Shannon capacity. These systems have also to obey physical laws such as the conservation of energy and the…
Correlation between the lens extension size and the broadside directivity of a hemielliptic dielectric lens antenna (DLA) fed by a primary feed with variable radiation pattern is studied in accurate manner. The problem is considered in…
In this paper, a new lower bound on spectral efficiency in the low-power wideband regime is derived and utilized to develop an improved estimate of the behavior of spectral efficiency above but in the vicinity of the Shannon limit.
In this opening presentation we will first recall the main characteristics of graphene conductivity and electromagnetic wave propagation on graphene-based structures. Based on these observations and different graphene antenna simulations…
The natural source of a magnetic dipole in antennas is typically an electrically small loop, which can be utilized in conjunction with an electric dipole to realize an electrically small Huygens' antenna. However, these antennas suffer from…
In this paper, the Q-factor expression for periodic arrays over a ground plane is determined in terms of the electric current density within the array's unit cell. The expression accounts for the exact shape of the array element. The…
Metasurfaces have emerged as a promising technology for the manipulation of electromagnetic waves within a thin layer. In planar ultrathin metasurfaces, there exist rigorous narrowband design methods, based on the equivalent surface…
This paper presents a method for the fast and accurate estimation of the gain pattern and maximum gain of an implanted antenna including the effect of the host body, under the assumption that the latter is electrically large. The estimation…
This paper investigates energy efficiency maximization for movable antenna (MA)-aided multi-user uplink communication systems by considering the time delay and energy consumption incurred by practical antenna movement. We first examine the…
Finite-aperture constraints render array design nontrivial and can undermine the effectiveness of classical sparse geometries. This letter provides universal guidance for fluid antenna array (FAA) design under a fixed aperture. We derive a…
Quantum emitters in confined arrays exhibit geometry dependent collective dynamics. In particular, nanoscopic regular polygon-shaped arrays can possess sub-radiant states with an exciton lifetime growing exponentially with emitter number.…