conae orbit tested, verified, and implemented roll, pitch, and yaw implemented

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