GeoSTAR was constructed to act as a "Geostationary AMSU." Below is information about the instrument itself. Also available is the GeoSTAR development timeline (PDF, 5.22 MB).
- Sparse array employed to synthesize large aperture
- Cross-correlations ⇒ Fourier transform of Tb field
- Inverse Fourier transform on ground ⇒ Tb field
- Optimal Y-configuration: 3 sticks; N elements
- Each element is one I/Q receiver, 3.5λ wide (2.1 cm @ 50 GHz; 6 mm @ 183 GHz)
- Example: N = 100 ⇒ Pixel = 0.09° ⇒ 50 km at nadir (nominal)
- One Y per band, interleaved
- A/D converter; Radiometric power measurements
- Cross-correlator - massively parallel multipliers
- On-board phase calibration
- Controller: accumulator ⇒ low D/L bandwidth
System DevelopmentGeoSTAR development is also proceeding through partnerships, such as with OmniSys of Sweden. For detailed information, be sure to read a recent report on correlator ASIC test results.