Related papers: Aperture Arrays for the SKA: Dense or Sparse?

The low frequency component of the Square Kilometre Array (SKA1-Low) will be an aperture phased array located at the Murchison Radio-astronomy Observatory (MRO) site in Western Australia. It will be composed of 512 stations, each of them…

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…

The Low Frequency Array (LOFAR) is a new generation of electronic radio telescope based on aperture array technology. The telescope is being developed by ASTRON, and currently being rolled out across the Netherlands and other countries in…

We describe the design and performance of the Engineering Development Array (EDA), which is a low frequency radio telescope comprising 256 dual-polarisation dipole antennas working as a phased-array. The EDA was conceived of, developed, and…

Radio emission from stars can be used, e.g., to study ionized winds or stellar flares. The radio emission is faint and studies have been limited to few objects. The Square Kilometer Array (SKA) will bring a survey ability to the topic of…

LOFAR, the Low-Frequency Array, is a powerful new radio telescope operating between 10 and 240 MHz. LOFAR allows detailed sensitive high-resolution studies of the low-frequency radio sky. At the same time LOFAR also provides excellent short…

This paper considers near-field multiuser communications based on sparse arrays (SAs). First, for the uniform SAs (USAs), we analyze the beam gains of channel steering vectors, which shows that increasing the antenna spacings can…

We construct a pipeline for simulating weak lensing cosmology surveys with the Square Kilometre Array (SKA), taking as inputs telescope sensitivity curves; correlated source flux, size and redshift distributions; a simple ionospheric model;…

Mixing between dark photons and visible photons leads to substantial anisotropies in the cosmic microwave background due to resonant conversions of visible photons into dark photons in baryonic matter found in dark matter halos. In this…

Radio interferometers are phased arrays producing high-resolution images from the covariance matrix of measurements. Calibration of such instruments is necessary and is a critical task. This is how the estimation of instrumental errors is…

Backed by advances in digital electronics, signal processing, computation, and storage technologies, aperture arrays, which had strongly influenced the design of telescopes in the early years of radio astronomy, have made a comeback. Amid…

Sparse array (SA) geometries, such as coprime and nested arrays, can be regarded as a concatenation of two uniform linear arrays (ULAs). Such arrays lead to a significant increase of the number of degrees of freedom (DOF) when the…

This paper summarizes the design process and metrics for the latest antenna design for 2 radio telescopes, SKALA4 for the SKA1-LOW instrument and the V-feed for the HERA telescope. In the paper we briefly describe the main features of the…

This paper studies hybrid beamforming for active sensing applications, such as millimeter-wave or ultrasound imaging. Hybrid beamforming can substantially lower the cost and power consumption of fully digital sensor arrays by reducing the…

Most of the pulsar science case with the Square Kilometre Array (SKA) depends on long-term precision pulsar timing of a large number of pulsars, as well as astrometric measurements of these using very long baseline interferometry (VLBI).…

Radio astronomy has entered its golden era, with many revolutionary facilities such as SKA, ngVLA, and LOFAR2.0 coming online in the next decade. These facilities are certain to redefine radio astronomy. However, on smaller scales-such as…

Both Phase 1 of the Square Kilometre Array (SKA1) and the full SKA have the potential to dramatically increase the science return from future astrophysics, heliophysics, and especially planetary missions, primarily due to the greater…

This article investigates the influential role of flexible antenna array curvature on the performance of 6G communication systems with carrier frequencies above 100 GHz. It is demonstrated that the curvature of flexible antenna arrays can…

We have measured the relative permeability of split-ring resonator (SRR) arrays used in metamaterials designed to have $\mu^\prime< 0$ over a narrow range of microwave frequencies. The SRR arrays were loaded into the bore of a loop-gap…

Sparse arrays have been widely exploited in radar systems because of their advantages in achieving large array aperture at low hardware cost, while significantly reducing mutual coupling. However, sparse arrays suffer from high sidelobes…