Difference between revisions of "LFI design, qualification, and performance"

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[[File:lfi_instrument.jpg]]
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[[File:lfi_instrument.jpg|100px|Left panel: the LFI instrument with main thermal stages, focal plane, waveguides and sorption cooler piping highlighted. Right panel: labelling of feed horns on the LFI focal plane.]]
[[File:rca_schematic.jpg]]
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[[File:LFIblockdiagram.jpg|100px|Block Diagram of LFI]]
[[File:phase_switch_operation.jpg]]
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[[File:rca_schematic.jpg|100px|A complete RCA from feed-horn to analog voltage output. The insets show the OMT, the details of the 20 K pseudo-correlator and of the back-end radio-frequency amplification, low-pass filtering, detection and DC amplification]]
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[[File:phase_switch_operation.jpg|100px|Close-up of the two front-end modules of an RCA. There are four phase switches, labelled A, B, C and D. Each switch can be fixed in one of its two positions (labelled as 0, 1) or switch at 4 kHz between 0 and 1. Phase switches are clocked and biased by the DAE in pairs: A/C and B/D (see text for further explanation).]]
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a tunable ''offset'', <math>O_{DAE}</math>, then it amplifies the signal with a tunable ''gain'', <math>G_{DAE}</math>,
 
a tunable ''offset'', <math>O_{DAE}</math>, then it amplifies the signal with a tunable ''gain'', <math>G_{DAE}</math>,

Revision as of 14:25, 18 October 2012

Overview[edit]

The first :

  • uno
  • due
    • tre
    • quattro

Only a.

The LFI description[edit]

Each LFI radiometer g [math]V_{sky}[/math], [math]V_{load}[/math] signals at the frequency of the phase switch. By changing the phase switches configuration, the output can be a sequence of either [math]V_{sky}[/math] or [math]V_{load}[/math] signals.


Left panel: the LFI instrument with main thermal stages, focal plane, waveguides and sorption cooler piping highlighted. Right panel: labelling of feed horns on the LFI focal plane. Block Diagram of LFI A complete RCA from feed-horn to analog voltage output. The insets show the OMT, the details of the 20 K pseudo-correlator and of the back-end radio-frequency amplification, low-pass filtering, detection and DC amplification Close-up of the two front-end modules of an RCA. There are four phase switches, labelled A, B, C and D. Each switch can be fixed in one of its two positions (labelled as 0, 1) or switch at 4 kHz between 0 and 1. Phase switches are clocked and biased by the DAE in pairs: A/C and B/D (see text for further explanation).


a tunable offset, [math]O_{DAE}[/math], then it amplifies the signal with a tunable gain, [math]G_{DAE}[/math],

Radiometer Chain Overall Design
Radiometer Array Assembly
REBA
Radiometer Chain Overall Design


Instrument On-board Software
Instrument Operations
Instrument Budgets


LFI Ground Tests[edit]

LFI In-flight Calibration[edit]

LFI Performance[edit]

Instrument Scientific Performance


Instrument Technical Performance

(Planck) Low Frequency Instrument

LFI Data Acquisition Electronics

LFI Radiometer Electronics Box Assembly