Mixer Unit for HIFI Band 2 (640-800 GHz)
The mixer unit consists of different functional groups. Klick on the active purviews to read more.
The two mixer units - one for each polarization - are part of the Focal Plane subsystem (FPs/s). The common optics assembly of the FPs/s divides the astronomical and local oscillator signals over seven mixer assemblies, one for each HIFI frequency band. The frequency coverage of these bands is from 480 to 1910 GHz.
The mixer units for HIFI band 2 will receive combined radiation from the space and the reference signal from the Local Oscillator subsystem (LOs/s). The mixer units mix these signals and produce Intermediate-Frequency signals (4-8 GHz). These IF signals are fed to isolators that are at the same temperature as the mixer units. The IF signals are propagated via coaxial cables to a second isolator followed by a preamplifier. Two identical mixer units are used in a Double Side Band mode (DSB).