COBRAS/SAMBA High Frequency Instrument

COBRAS/SAMBA carries a High Frequency Instrument (LFI) which is envisaged to use cooled bolometers operating at about 0.1 to 0.3 K. A block diagram of the HFI is shown in the next figure and summarized in the following table.

Block Diagram of Cooled LFI This figure shows a sketch of the configuration of the HFI for an actively cooled concept. The main spacecraft is at abou 300K, the payload instrument area (focal plane) is designed to be cooled passively via radiation to about 65 K and active coolers can be used to bring the HFI fron-end bolometers to about 0.1 K and JFET preamplifiers to about 20 K. This action results in very good sensitivity.

HFI Schematic Chart