Metasurfaces have provided a novel and promising platform for realizing compact high-performance optical devices. The conventional metasurface design approach assumes periodic boundary conditions each element, which is inaccurate in most cases since near-field coupling effects between elements will change when the element surrounded by nonidentical structures. In this paper, deep learning propo...

Adaptive switching between multiple-input multiple-output (MIMO) transmission strategies like diversity and spatialmultiplexing is a flexible approach to respond to channel variations. It is desirable to obtain accurate estimates of the switching points between these transmission schemes to realize the capacity gains made possible by adaptive switching. In this paper, it is shown that the accur...

Spatially heterogeneous intensities of environmental signals are common in nature, being caused, e.g., by rugged or curved surfaces leading to varying angles of incidence and intensities. In this work, we perform numerical studies of one-dimensional arrays of coupled phase oscillators driven by a periodic signal with spatially heterogeneous amplitude, considering both random and gradual amplitu...

Based on the beamspace transform and the rank reduction theory (RARE), a fast direction of arrival (DOA) estimation algorithm in the presence of an unknown mutual coupling is proposed for uniform circular arrays (UCAs). Via relying on the circular symmetry and expanding the mutual coupling into a limited number of phase modes, the azimuth estimates are able to be obtained without the exact know...

This Letter presents an investigation on the effects of mutual coupling in a metamaterial comprising two sets of electric-LC (ELC) resonators with different resonance frequencies. Through simulation and experiment, it is found that the two resonances experience significant shifting and weakening as they become spectrally close. An equivalent circuit model suggests that inductive coupling among ...

Antenna array beamformers suffer from performance deterioration in the presence of mutual coupling (MC) between array sensors. In this paper, we present a theoretical analysis in terms of the output signal-to-interference-plus-noise ratio (SINR) for the performance of antenna array beamformers under MC effects. Based on the model of a distortion matrix to encapsulate the MC effects, a closed-fo...

A study of the capacity of multiple element antenna systems is presented, with particular emphasis on the effect that mutual coupling between the antenna elements has on the capacity. The results presented here shows, contrary to some earlier claims, that correlation between different channel coefficients as a function of antenna spacing, can in fact decrease when the mutual coupling effect is ...

In patch antennas, characteristics such as high gain, beam scanning, or steering capability are possible only when discrete patch elements are combined to form arrays. The elements of an array may be spatially distributed to form a linear, planar, or volume array. Planar arrays have elements distributed on a plane. Planar array configurations are extensively used in both communication and radar...