Out-of-focus holography at the Effelsberg telescope
Out-of-focus holography at the Effelsberg telescope
Context. Out-of-focus (OOF) holography can be used to determine the aperture deformations of radio telescopes that lead to errors in the phase of the complex aperture distribution. In contrast to traditional methods, OOF holography can be performed without a reference antenna, which has a number of practical advantages. Aims. The …