Related papers: Adapting Active Reflector Technology for greater s…

The Five-hundred-meter Aperture Spherical radio Telescope (FAST) has the largest aperture and a 19-beam L-band receiver, making it powerful for investigating the neutral hydrogen atomic gas (HI) in the universe. We present HiFAST…

This paper describes a programme to map large-scale cosmic structures on the largest possible scales by using the Five hundred metre Aperture Spherical Telescope (FAST) to make a 21 cm (red-shifted) intensity map of the sky for the range…

We describe the results from a new instrument which combines Lucky Imaging and Adaptive Optics to give the first routine direct diffraction-limited imaging in the visible on a 5m telescope. With fast image selection behind the Palomar AO…

The performance of an adaptive optics (AO) system on a 100m diameter ground based telescope working in the visible range of the spectrum is computed using an analytical approach. The target Strehl ratio of 60% is achieved at 0.5um with a…

The Five-hundred-meter Aperture Spherical Telescope (FAST) is the world's largest single-dish radio telescope, and the search for extraterrestrial intelligence (SETI) is one of its five key science objectives. We conducted a targeted…

Stray radiation is a considerable challenge for radio telescopes, requiring careful assessment due to its effects. This is crucial when the strong background flux from side lobes significantly affects the total flux, especially for extended…

The Five-hundred-meter Aperture Spherical Telescope (FAST), the world's largest single-dish radio telescope, lists the search for extraterrestrial intelligence (SETI) as one of its key scientific objectives. In this work, we present a…

We describe a Phased Array Feed (PAF) system, called Apertif, which will be installed in the Westerbork Synthesis Radio Telescope (WSRT). The aim of Apertif is, at frequencies from 1.0 to 1.7 GHz, to increase the instantaneous field of view…

In this paper, we propose an adaptive beam that adapts its divergence angle according to the receiver aperture diameter and the communication distance to improve the received power and ease the alignment between the communicating optical…

The Large Sky Area Multi--object Fibre Spectroscopic Telescope (LAMOST) is the largest (aperture 4 m) wide field of view (FOV) telescope and is equipped with the largest amount (4000) of optical fibres in the world. For the LAMOST North and…

The major cornerstone of future ground-based astronomy is imaging and spectroscopy at the diffraction limit using adaptive optics. To exploit the potential of current AO systems, we have begun a survey around bright stars to study…

Sensitivity and resolution of space telescopes are directly related to the size of the primary mirror. Enabling such future extremely large space telescopes or even arrays of those will require to drastically reduce the areal weight of the…

The Five-hundred-meter Aperture Spherical Radio Telescope (FAST) Core Array is a proposed extension of FAST, integrating 24 secondary 40-m antennas implanted within 5 km of the FAST site. This original array design will combine the…

In the present paper we consider the Type-2.x and Type-3.x extraterrestrial von-Neumann probes and study the problem of their detectability by the world's largest radio telescope: the Five-hundred-meter Aperture Spherical Radio Telescope…

The Five-hundred-meter Aperture Spherical radio Telescope(FAST) was launched on September 25,2016.From early 2017,we began to use the FAST wideband receiver,which was designed,constructed and installed on the FAST in Guizhou,China.The front…

Dynamic modification of the pattern of a reflector antenna system traditionally requires an array of feeds. This paper presents an alternative approach in which the scattering from a fraction of the reflector around the rim is passively…

The standing waves existed in radio telescope data are primarily due to reflections among the instruments, which significantly impact the spectrum quality of the Five-hundred-meter Aperture Spherical radio Telescope (FAST). Eliminating…

In view of extremely challenging requirements on design and optimization of future mobile communication systems, researchers are considering possibilities of creation intelligent radio environments by using reconfigurable and smart…

An ongoing limitation of terahertz spectroscopy is that the technique is generally limited to the study of relatively large samples of order 4 mm across due to the generally large size of the focal beam spot. We present a nested concentric…

As new large-scale astronomical surveys greatly increase the number of objects targeted and discoveries made, the requirement for efficient follow-up observations is crucial. Adaptive optics imaging, which compensates for the image-blurring…