Quasi-Optical design of K, Q and W-band receiver system for 40-meter Thai National Radio Telescope (40m TNRT)

We report a preliminary Quasi-optics design of the simultaneous K-Q-W band receiver system for the 40m Thai Nation Radio Telescope (TNRT) by National Astronomical Research Institute of Thailand (NARIT) under the scope of “Radio Astronomy Network and Geodesy for Development (RANGD)” project. The antenna's specifications allow the observing frequency from 0.3 GHz to 115 GHz. The receivers can be installed on both primary and secondary focus. The position and beam waist of all reflectors or mirrors and receiver feeds are calculated with quasi-optic and Gaussian beam principles to determine the beam waist to find optimal alignment of the optical components. We obtain preliminary calculations of the beam waist for feed design of K, Q, and W band receivers which are 29.81 mm, 22.20 mm and 7.10 mm, respectively. Further investigations of the efficiency of the designed will be done with specialized simulation software.