PAYLOAD | firspex

FIRSPEX: Payload

In the past (Herschel HIFI) far-infrared observations from space meant need for cryogenic cooling.

Cryo-cooling to 4K via mecahnical coolers provides relaible long mission lifetime.

Superconducting mixers offer best sensitivity <=1THz and have good heritage (ALMA etc.) and for space Herschel-HIFI

At frequencies At >1THz Superconducting HEB devices provide adequate sensitivity.

Alternative is the Schottky diode mixer.

FIRSPEX-M5 uses superconducting SIS/HEB mixers SIS/HEB (baseline)

but also explores the possibility of Schottky technology.

Spectral resolution requirement ⇒ heterodyne receiver technique.

THz frequency mixing used for front-end.

High-speed digital fast Fourier Transform spectrometer (FFTS) for back-end.

Cannot encompass entire frequency range via a single receiver ⇒ Subdivide into 5 discrete channels.