Speaker
Description
The Square Kilometre Array (SKA) telescope will provide unprecedented sensitivity across a wide frequency range, combined with high resolution and survey speed, offering the astronomical community a state-of-the-art instrument to address ambitious scientific objectives and advance our understanding of the Universe’s history.
During the preconstruction phase of the SKAO project, the Dish Consortium, together with Onsala Space Observatory, developed a prototype of the Band 1 Single Pixel Feed. This prototype underwent several years of development and testing in Sweden, Canada and on the MeerKAT telescope in South Africa, a precursor to SKA-Mid. After successfully passing its design review, it was selected by SKAO for full implementation.
The feed package is mounted on the telescope indexer and directly exposed to the environment. Under the Band 1 Single Pixel Feed Engineering Construction Contract, awarded to AAC Omnisys [AAC Clyde Space], the task is to finalize the design, manufacture, assemble, install, and test 80 complete Band 1 Single Pixel Feed systems, each weighing around 180 kg (with mechanical parts produced by MECHA and HPG AB). An initial delivery of four prototypes will be installed in South Africa.
The Band 1 system is an ambient-temperature feed package covering frequencies from 350 to 1050 MHz. A dual linear polarized quad-ridge feed horn converts electromagnetic signals focused by the SKA dish. Two low-noise amplifiers (LNAs, Low Noise Factory AB) are integrated directly into the ridges, amplifying the signals by approximately 40 dB. The first-stage LNA also incorporates a directional coupler to inject calibration noise before amplification. Signal conditioning continues in the Band 1 Feed Package Controller (ACORDE), which contains amplifiers, noise diode circuitry, temperature stabilization, and control electronics. The horn aperture is shielded by a radome (FORMPLAST), while a sun shield (MOMEK) reduces solar heating and protects against rain.
Assembly and testing will be carried out at Omnisys in Gothenburg, RISE in Borås, and on-site in South Africa. Site acceptance of the feeds is planned for late 2025, after which AAC Omnisys will begin serial production of 80 units for SKAO.
