Radio Telescopes | Jeff Mangum

ngVLA Antenna Memo 12: Verification Testing for the ngVLA 18m Prototype Antenna

Mangum 2022

This memo presents an assessment of measurement system options and associated procedures which will enable customer acceptance testing of the ngVLA 18m prototype antenna. Detailed design and analysis of testing procedures for surface, pointing, and path length performance are provided, as these three performance requirements drive software and hardware development for the ngVLA 18m antenna customer acceptance testing. Recommendations for how to perform surface, pointing, and path length performance measurements are provided.

Holographic measurement sensitivity modeling. Equation 13 from the memo as a function of frequency. Contours are number of reference antennas for a holography grid point integration times of 5 seconds and holography target source fluxes (S). VLA receiver zenith system temperatures have been taken from the XML file which feeds the ETC. Vertical black dotted lines mark receiver band edges. A black arrow indicates the holography measurement sensitivity target of 35 μm

Holographic Measurements of Radio Telescope Antennas

Baars et al. 2007

Using both near- and far-field holographic imaging I have been involved in the surface performance characterization of a number of radio telescopes.

Near-field holographic imaging of the ALMA NA DV06 antenna

Radio Telescope Positioning Characterization

Mangum et al. 2006

Using a variety of measurement systems, including optical pointing telescopes, accelerometers, and traditional radio source position measurements, I have studied the positioning performance of a number of radio telescopes.

Summaries of the all-sky pointing, offset pointing, and fast-switching performance for the ALMA Vertex production antennas.