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CONAE orbit tested, verified, and implementedRoll, pitch, and yaw implemented
Antenna pattern for Aquarius scale model implemented
Rudimentary Thermal Model and Thermistors implemented
Land Emissivity Model in progress
There now exists fully functional (but not complete) and tested code for:Radiometer Level-1a to Level 1b Radiometer Level-1b to Level 2
Simplicity and readability is a major objective in writing source code1. Well structured (no spaghetti code)2. Thoroughly commented3. Minimize lines of code4. Have code directly relate to mathematics5. Geolocation is all done in vector notation6. Avoid too much modularization
Initial Closure Test have been completedWe are now running a complete end-to-end Aquarius on-orbit simulatorEarth Scenes TB TA Counts L1A L1B L2B Earth ScenesSimulator outputs radiometer and thermistor counts in telemetry block format
Progress since last Algorithm Workshop
Implement Ruf RFI flagging
Implement other QC flags
Further test. review, and finalize radiometer sensor model
Adapt geolocation to handle of orbit-maneuvers
Implement galactic radiation into simulation and L2b algorithm
Implement solar backscatter into L2b algorithm
For the next year, there will be continual updates and improvements
Things to Do(A partial list)
CONAE Orbit
• The simulator now uses the CONAE orbit
• Histogram shows some differences between JPL and CONAE mostly at the perigee. RMS difference in altitude within an orbit is 108m.
• Simulated Nadir Latitude, Longitude, and Altitude agree with CONAE to better than 250 meters
• Roll, Pitch, and Yaw are now simulated assuming geodetic mission
Scale Model Gain Pattern
• Includes– surface temperature and moisture from NCEP (simultaneous)– Surface type (bare, ice, grass, crop, tree (tropical, deciduous, conifer)) from
EUROCLIMAP monthly/annual climatology– Soil roughness effect– Vegetation effect– L-band dielectric model of Dobson et al. 1985
Land Emissivity Model
LNA Det
Amp V/F V out
+
T r Rec Noise
Temp
Z Zero
Offset
T o Ref Load
Temp
G = Gain Dicke Switch
+
L T 6 To
Computer
BPF
B = Bandwidth
Noise T
N
T i
+
Noise T
CND
+
L 6 T 6 L 5 T 5 L 4 T 4 L 3 T 3 L 2 T 2 L 1 T 1 Loss, Temp
Zone 6 Zone 5 Zone 4 Zone 3 Zone 2 Zone 1
T ’ A Radiometer S/S Reference
T AA
RFE RBE
Diplexer OMT Coupler
OMT Feed Reflector Dicke & coup
T ’’ A Feed horn Reference
31 37 34
70 1
38 30 -34
682
3
4
248 244 288 289 289 290 Temp
1.0 1.01 1.04 1.03 1.05 1.27 Loss
TND=500K, TDL=290K, TCND=500K
TA to Voltage (count) Forward Simulation
3rd Stokes Calibration: gain and offset
, , , , , ,
, , , , , ,
, , , , , ,
, , , , , ,
1
1
1
1
p DL DL m DL DL v DL h DLpv mv
p DL ND m DL ND v DL h NDph mh
p ND DL m ND DL v ND h DLp m
p ND ND m ND ND v ND h ND
v v T TG G
v v T TG G
v v T To o
v v T T
• Estimating Gpv, Gph, op, Gmv, Gmh, om
– 3 calibration looks are needed (used 4 looks - overdetermined)
• Estimating GpU (same for GmU)
– 4th calibration look (vCND) is used
– vp,earth=earth count at 10milisec interval
– TCND,v and TCND,h are set to TCND/2
, , , ,p CND p earth CND v pv CND h phpU
CND CND
v v T G T GG
T T
3rd Stokes Calibration: gain and offset• TU produces vp and vm signals
• Thus vp and vm are used to estimate TU
• Yet vp and vm are affected also by Tv and Th
• Manipulating the forward equation yields
– First, retrieve earth-view Tv and Th
– Then, estimate Gpv, Gph, Gmv, Gmh, GpU, GmU, op, om.
– Then, remove contributions of Tv and Th to vp and vm
– Finally, account for GpU, GmU, op, om
2 2
1 p p pv ph vU pU mU
m m mv mh hpU mU
v o G G TT G G
v o G G TG G
• Simulates, based on ATBD (Piepmeier/Pellerano/Wilson/Yueh 2005) – radiometer (Ta counts)
– Ta retrieval (counts Ta)
• Used minimum 2 calibration looks for v-/h-pol and 4 calibration looks for 3 rd Stokes
• Fully used correlated noise diodes
• Accuracy is better than 0.01K
Testing TA Counts TA
Earth SceneOcean: Salinity, SST, Wind fieldsLand: Soil moisture, vegetation type, LSTIce: Ice type and temperatureAtmosphere (including limb): NCEP profiles
TA IntegrationFull 4-Stokes Integration over Earth and Space
SunYear 2000 actual values Easily scalable
Cosmic Background 2.7 K
GalaxyTo be implemented
Faraday Rotation Actual TEC valuesEarth Magnetic Field
Orbiting AntennaCONAE Orbit ParametersRoll/Pitch/Yaw now includedAquarius Scale Model patterns
Radiometer Piepmeier Forward Model for TA to counts
TB TB
TB
TB
TBrotated
TA
Radiometer Counts
Orbiting Thermal ModelSimple harmonic of orbit position
Thermistor Response Func. Linear with temperature
Temperatures
Thermistor Counts
Orbit Position
End-to-End Aquarius On-Orbit Simulator: Part 1
End-to-End Aquarius On-Orbit Simulator: Part 2
Radiometer Counts Thermistor Counts
Pre-FormatterFormat in Group, Block, and Sub-Block Structure
Telemetry FormatterFormat in Group, Block, and Sub-Block Structure
Scatterometer Data Platform Data
Simulated Downlink Telemetry
Level-0 to Level-1A Processing
Level-1A to Level-1B Processing
Level-1B to Level-2 Processing
Level-2 to Level-3 Processing
Antenna Temperature
TOA Brightness TemperatureSwath Salinity, SST, wind, etc
Time-Averaged Salinity Fields
Aquarius
Sunsunlat,sunlonsundis
SolarReflection refllatrefllonreflinc
Gain AnglesDirect and Reflected Solartht_global_sun(2)phi_global_sun(2)
Boresight cellatcelloncelinccelazmcelpra
SolarBackscattersunincsunazmsunglt
BoresightReflectionglxlatglxlon(J2KM)
Moonmoonlat,moonlonmoondis
Earth Surface
Explanation of L1B Geolocation Arrays
L1A_to_L2A Module (part 1)
L1A_to_L2A Module (part 2)
Source Code (example 1)
Source Code (example 2)
Source Code (example 3)
Source Code (example 4)
Source Code (example 5)
Source Code (example 6)
Source Code (example 7)
Source Code (example 8)
Include Files
Tested on a half of orbit 1
,
, , , ,
, ,
14
14
toa
Earth
toa ocean toa land
Earth
ocean land
dAA
dAA
A B
B B
A A
T GΨT
GΨ T T
T T
Salinity retrieval over coastal seas (ongoing)
• APC (antenna pattern correction) coefficients are trained with 4-integrated Ta
, , ,
4est ocean ocean
ocean
APCdAA
B AT T
G
Salinity retrieval over coastal seas (ongoing)
land emission correctedwith land emissionland fraction
• Can get closer to the coast by 100-200km• Simultaneous correction of land emission over the coastal ocean is possible