Quasi-optical design and analysis of the millimeter-wave bolometric interferometer (MBI)

This paper presents work being done on the optical design and analysis of the beam combiner for the millimeter-wave bolometric interferometer (MBI), a ground based instrument designed to measure the polarization anisotropies of the cosmic microwave background at a central frequency of 90 GHz. Interferometry has never before been used to carry out such measurements at this frequency, nor using incoherent bolometers as detectors. MBI will therefore act as a prototype for this type of system and must be modeled in detail to ensure that its operation is fully understood.