This paper describes the design and measured performance of the band 2 (L-band, 950 MHz–1760 MHz) cryogenic receiver front-end of the Square Kilometre Array (SKA) radio telescope dish array. The system comprises a wide flare-angle axially corrugated conical horn, a dual linearly polarized orthogonal mode transduce, a noise injection directional coupler, and two amplification stages. Its compact design and cryogenic cooling allow for a very low receiver noise temperature, and it presents another step in the continuous improvement of the noise temperature performance. A Gifford–McMahon cooler physically cools the OMT with its integrated directional coupler to around 70 K, and the first stage low-noise amplifier to about 15 K. A bespoke measurement setup was designed to measure the system’s performance. The measured receiver noise is about 6 K across the frequency band.
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