Subscribe to the gold package and get unlimited access to Shamra Academy
Register a new userPhase synchronisation system receiver module for the Mid-Frequency Square Kilometre Array
94
0
0.0
(
0
)
Ask ChatGPT about the research
No Arabic abstract
Next generation radio telescopes, such as the Square Kilometre Array (SKA) and Next Generation Very Large Array (ngVLA), require precise microwave frequency reference signals to be transmitted over fiber links to each dish to coherently sample astronomical signals. Such telescopes employ phase stabilization systems to suppress the phase noise imparted on the reference signals by environmental perturbations on the links; however, the stabilization systems are bandwidth limited by the round-trip time of light travelling on the fiber links. A phase-locked Receiver Module (RM) is employed on each dish to suppress residual phase noise outside of the round-trip bandwidth. The SKA RM must deliver a 3.96 GHz output signal with 4 MHz of tuning range and less than 100 fs of timing jitter. We present an RM architecture to meet both requirements. Analytical modelling of the RM predicts 30 fs of output jitter when the reference signal is integrated between 1 Hz and 2.8 GHz. The proposed RM was conceived with best practice electromagnetic compatibility in mind, and to meet size, weight and power requirements for the SKA dish indexer. As the ngVLA reference design also incorporates a round-trip phase stabilization system, this RM may be applicable to future ngVLA design.
rate research
Read More
We review the current status of the Square Kilometre Array (SKA) by outlining the science drivers for its Phase-1 (SKA1) and setting out the timeline for the key decisions and milestones on the way to the planned start of its construction in 2016. We explain how Phase-2 SKA (SKA2) will transform the research scope of the SKA infrastructure, placing it amongst the great astronomical observatories and survey instruments of the future, and opening up new areas of discovery, many beyond the confines of conventional astronomy.
The SKA at mid and low frequencies will be constructed in two distinct phases, the first being a subset of the second. This document defines the main scientific goals and baseline technical concept for the SKA Phase 1 (SKA_1). The major science goals for SKA_1 will be to study the history and role of neutral Hydrogen in the Universe from the dark ages to the present-day, and to employ pulsars as probes of fundamental physics. The baseline technical concept of SKA_1 will include a sparse aperture array operating at frequencies up to 450 MHz, and an array of dishes, initially operating at frequencies up to 3 GHz but capable of 10 GHz in terms of antenna surface accuracy. An associated Advanced Instrumentation Program (AIP) allows further development of new technologies currently under investigation. Construction will take place in 2016-2019 at a total capital cost of 350Mtexteuro, including an element for contingency. The cost estimates of the SKA_1 telescope are now the subject of a more detailed and thorough costing exercise led by the SKA Project Development Office (SPDO). The 350 Mtexteuro total for SKA_1 is a cost-constrained cap; an additional contingency is to reduce the overall scope of the project. The design of the SKA_1 is expected to evolve as the major cost estimates are refined, in particular the infrastructure costs at the two sites. The SKA_1 facility will represent a major step forward in terms of sensitivity, survey speed, image fidelity, temporal resolution and field-of-view. It will open up new areas of discovery space and demonstrate the science and technology underpinning the SKA Phase 2 (SKA_2).
In this paper we describe the system design and capabilities of the Australian Square Kilometre Array Pathfinder (ASKAP) radio telescope at the conclusion of its construction project and commencement of science operations. ASKAP is one of the first radio telescopes to deploy phased array feed (PAF) technology on a large scale, giving it an instantaneous field of view that covers 31 square degrees at 800 MHz. As a two-dimensional array of 36x12m antennas, with baselines ranging from 22m to 6km, ASKAP also has excellent snapshot imaging capability and 10 arcsecond resolution. This, combined with 288 MHz of instantaneous bandwidth and a unique third axis of rotation on each antenna, gives ASKAP the capability to create high dynamic range images of large sky areas very quickly. It is an excellent telescope for surveys between 700 MHz and 1800 MHz and is expected to facilitate great advances in our understanding of galaxy formation, cosmology and radio transients while opening new parameter space for discovery of the unknown.
The Square Kilometre Array (SKA) will be both the largest radio telescope ever constructed and the largest Big Data project in the known Universe. The first phase of the project will generate on the order of 5 zettabytes of data per year. A critical task for the SKA will be its ability to process data for science, which will need to be conducted by science pipelines. Together with polarization data from the LOFAR Multifrequency Snapshot Sky Survey (MSSS), we have been developing a realistic SKA-like science pipeline that can handle the large data volumes generated by LOFAR at 150 MHz. The pipeline uses task-based parallelism to image, detect sources, and perform Faraday Tomography across the entire LOFAR sky. The project thereby provides a unique opportunity to contribute to the technological development of the SKA telescope, while simultaneously enabling cutting-edge scientific results. In this paper, we provide an update on current efforts to develop a science pipeline that can enable tight constraints on the magnetised large-scale structure of the Universe.
The Square Kilometre Array (SKA), currently under design, will be a transformational facility for studying the Universe at centimetre and metre wavelengths in the next decade and beyond. This paper provides the current best estimate of the anticipated performance of SKA Phase 1 (SKA1), using detailed design work, before actual on-sky measurements have been made. It will be updated as new information becomes available. The information contained in this paper takes precedent over any previous documents.
Log in to be able to interact and post comments
comments
Fetching comments
Sign in to be able to follow your search criteria
