Prototype

Proof of concept

To establish a proof of concept and validate the observational strategy that underlies the COSMOCal project, we designed and assembled a prototype instrument designed to operate within the atmospheric window centered at 260 GHz. The first image on left details the main components: 

• A radio frequency chain that generates a monochromatic signal at 260 GHz and directs it through a waveguide to a conical horn. The electronic chain design is based on that of the 300 GHz channel of the space-qualified JUICE-SWI instrument developed at Observatoire de Paris-PSL.

• A metal grid polarizer that ensures the purity of the polarized signal.

• An optical laser to illuminate the grid polarizer generating a diffraction pattern, enabling to recover and monitor the alignment of the wires, and thereby the orientation of the signal polarization output.

• Optics to focus the image of the diffraction pattern onto a CDD camera with a flip mirror to alternatively image ground landmarks onto the CCD camera to determine the 3D position and orientation of the COSMOCal source by photogrammetry.