Beam Waveguide and Receiver Optics for the SMA

This paper gives an outline of the optics design for the Submillimeter Array. It emphasizes the natural frequency-independence and simplicity of Fresnel imaging principles as the starting point for the optics design, with multi-mode Gaussian beam methods used as a computational tool for working out the detailed behavior. A calculation of the coupling loss at the beam waveguide mirrors is presented as an example of the design method.