Frontend Signal Processing Design for a cryogenic PAF prototype of FAST

For large reflector radio telescopes, cryogenic phased array feed (PAF) has the great potential on enhancing the telescope's performance and thus PAF becomes one of the research frontiers in the field of radio astronomy. The Joint Laboratory for Radio Astronomy Technology (JLRAT) team has been studying on PAF theories and key technologies and developing a cryogenic prototype for the Five hundred meter Aperture Spherical Telescope (FAST). This paper is to present the current progress on the frontend signal processing devices including the signal processing framework design, the system integration and key components development.