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The radiometer has not a wideband channel because of the
electromagnetic interferences at receiving frequency range.
Eight intelligent narrowband channels are associated to
respective TV-channels.
Technical information:
Central frequency of narrow channels
MHz |
Filter frequency bandwidth
MHz |
Respective TV-channels |
| 550 |
542 - 558 |
30 - 31 |
| 566 |
558 - 574 |
32 - 33 |
| 582 |
574 - 590 |
34 - 35 |
| 598 |
590 - 606 |
36 - 37 |
| 614 |
606 - 622 |
38 - 39 |
| 630 |
622 - 638 |
40 - 41 |
| 646 |
638 - 654 |
42 - 43 |
| 662 |
654 - 670 |
44 - 45 |
| Front end amplifier |
ξεντ |
| Physical temperature |
310 K |
| System noise temperature |
125 K |
Sensitivity synthesized (8 channels)
( = 1 s) |
25 mK |
| Design |
Noise Added Radiometer |
| Operating mode |
Single - beam mode |
| Feed |
Three-frequency feed with
matched phase center
(the same for 13 and 31 cm) |
| Polarization |
Left Circular Polarization (LCP)
or
Right Circular Polarization (RCP) |
| Calibration |
Noise generator |
Simplified block-diagram of the radiometer :
- PF - primary feed,
- DC1, DC2 - directional couplers,
- CI - cooled ferrite isolator,
- GM - p-i-n diode gain modulator,
- BPF - band-pass filter,
- NG1 - noise generator for calibration,
- NG2 - balance noise generator,
- A - noise power control attenuator,
- M, S - p-i-n diode modulator/switch,
- ADC - analog-to-digit converter,
- DSP - digital signal processor.
Unit 1. Front-end amplifier and noise generators
Unit 2. Back-end amplifiers
Unit 3. Power devider, BPFs, detectors, LFAs and ADC
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= 49 cm