SAOCOM (Satélite Argentino de Observación Con Microondas) es un sistema de dos satélites de observación terrestre de la agencia espacial de Argentina, CONAE. Estarán equipados con un radar de apertura sintética polarimétrico en banda L.
A synthesis of the SAR instrument general characteristics is depicted in the table below.
Central Frequency: L Band (1,275 GHz)
Observation orientation: To the right (with the possibility to also make observations to the left)
Orbit type: frozen orbit; quasi circular; sun-synchronous; height: 620 km (approx.); ascending node local time, 06:12.15 am; orbit revisit cycle: 16 days (for one satellite); 8 days (for the constellation)
Space resolution: 10 to 100 m
Coverage: 30 to 350 km
Angle of incidence: 20 to 50 degrees
Absolute radiometric accuracy: 0,25 dB (for the entire Mission)
Relative radiometric accuracy: 0,05 dB (within the scene)
Further SAOCOM 1A characteristics:
- Operative, all quality requirements and resolution specifications are satisfied
- Technological, technological innovations aiming to performance improvement assessment are included
- Calibration, gathering measurements for SAR instrument calibration and noise estimations.
- Single (SP), the system transmits and receives in the same linear polarization (horizontal-H or vertical-V), meaning HH or VV.
- Double (DP), the system transmits in a given linear polarization and receives the two linear polarizations simultaneously, meaning HH and HV, or VV and VH.
- Quadrupolar (QP), the system transmits alternately both linear polarizations and receives simultaneously, meaning HH, HV, VH and VV.
- Circular Linear (CL-POL), the system transmits one circular polarization (right or left) and receives two linear polarizations simultaneously, meaning right-H and right-V or left-H and left-V.
SAOCOM 1A operation modes:
- StripMap SP, DP y QP
- TOPSAR Narrow SP, DP y QP
- TOPSAR Wide SP, DP y QP
- TOPSAR Wide CL-POL (designed exclusively for soil moisture assessing in the Pampa Húmeda region)
It is foreseen to have the following processing levels:
- Annotated Raw Data-AR, Level 0: the product is obtained from the binary data stream (Raw Data, RAW) and includes formatted synchronized data.
- Single Look Complex-SLC, Level 1A: the product is generated from Level 0 products. Complex data in slant range, radiometrically calibrated with no geometric corrections.
- Detected Image-DI, Level 1B: the product is generated from Level 0 products. Data projected to ground range, radiometrically calibrated and georeferenced.
- Ground Ellipsoid Corrected-GEC, Level 1C: the product is generated from Level 0 products, radiometrically calibrated, geocoded and georeferenced.
The Mission has three demonstration projects in course, based on soil moisture assessment over the Pampa Húmeda region (on surface and deepness). The area of interest includes almost 70M hectares and it is required to obtain soil moisture maps with a 700 x 700 m space resolution on an operative basis. Taking this into account, the instrument is required to perform acquisitions over the area of interest with a frequency better than 6 days and with a given dynamic range in order to allow Sigma Nought measurements between -35 to 5 dB.
Two of the three demonstration projects are devoted to Agriculture (carried out jointly with the Instituto Nacional de Tecnología Agropecuaria-INTA) and the third is devoted to Hydrology (carried out jointly with the Instituto Nacional del Agua-INA), with the following main objectives:
- Optimize sowing time and the use of fertilizing agents in the area of the Pampa region,
- Optimize the use of agrochemicals for crop disease control,
- Minimize the economic loss due to flooding and optimize the activities regarding future flooding warnings in Argentina.