e Maximum / Minimum Temperature of selected junction as
Multi frequency feed, Sky Horn, Reference Load and other
junctions.
e The scan rate and Mean value of scan rate is computed for
verifying time difference of successive scan.
e The variation of mean Scan rate signifies time/scan, speed
variation of successive scan, which effect the geometric
accuracy of the product.
3.2.2 Antenna Temperature Data (ATD) quantifies the
radiometric aspect of data product.
e The Percentage of flagged data quantifies the quality of
total data corrected for each sample scan of Antenna
temperature data. ‘
e The Center sample is unaffected by any component of
dual polarization (H & V). Global Dynamic range of
center sample signifies calibrated Antenna Temperature
range for each frequency. This parameter quantifies
system performance without antenna pattern correction.
e Mean and Standard deviation of Center sample for
Selected uniform targets quantifies Temperature
Sensitivity (homogeneity) for each frequency. This
parameter is monitored for quantifying relative
frequency behavior of local targets as and when
required.
3.2.3 Brightness Temperature Data (BTD) is final Sensor
Corrected and grided standard user product on which
radiometric & geometric accuracy of product is evaluated.
e The Percentage of flagged data quantifies quality of
radiometric corrected data after applying interim antenna
pattern correction.
e This Brightness Temperature range (based on the 0.1 %
rejection of lower & higher population of each frequency
distribution for corresponding Grid) signifies global
temperature variation with time.
e Target Temperature Homogeneity is measured by
estimating standard deviation of selected area. The
comparison is being attempted on sample basis over
Arabian Sea, Indian Ocean, Pacific Ocean, Libyan and
Sahara Desert.
The following comparison has been carried out for
Quantifying Radiometric performance over smaller area
with time.
1. Mean and standard deviation of same target for three-
grid resolution for given channel.
2. Relative channel behavior of different target for a
given date and Grid-1 resolution.
3. Relative channel behavior of same target for two
dates.
« MSMR geo location of BTD is defined as comparison of
assigned latitude /longitude of each sample from grided
data product with World Map Geo Location or with
system corrected reference Data Product value.
3.2.4 Geo Physical Parameter Data (For Each Grid) is
retrieved parameter after removing atmospheric effect and
relating respective channel data with Geophysical Parameters.
e The Percentage of flagged data quantifies the quality of
GPD over Sea region.
° Geo Physical Parameter Range: This signifies global
variation of Geo Physical parameters like Sea Surface
Temperature, Sea Surface Wind Speed, Cloud Liquid
Water and Water Vapor.
IAPRS & SIS, Vol.34, Part 7, “Resource and Environmental Monitoring”, Hyderabad, India,2002
e Mean and Standard deviation of selected Uniform area
quantifies the stability of Geo Physical Parameter for
corresponding area of Grid.
4.0 OBSERVATIONS
4.1 Sensor Performance:
4.1.1 Data Reception Quality: The engineering performance
of MSMR Payload at Subsystem level is comparable with
reference data and stable with respect to sensor specifications.
The trend of the sync loss and calibration data statistics
indicates consistent behavior since launch. The statistics of bad
sync & cal scan behavior of some days is shown in 2 oca
column of Table 6.
The trend of variation of standard deviation of scan rate has
varied from 7 to 30 counts as shown in 5" column of Table 6.
Date Of Bad Bad Mean Scan BTD
Pass Sync Cal Scan Rate flagged
Scan | Scans Rate Std data
Dev %
10-07-99 27 15 5375.95 7.68
22-04-00 | 31 6 5375.92 10.0 0.098
01-08-00 29 8 5375.97 22.40 0.069
30-09-00 28 4 5375.94 | 28.71 0.069
01-10-00 29 6 5375.90 28.15 0.025
16-01-01 32 4 $375.07. 1:22,85 0.068
MEAN 29.3 | 7.166 | 5375.94 | 19.96 0.0658
STDEV 1.86 | 4.119 | 0.02786 | 9.032 | 0.02610
MAX 32 15 1:5375.97.1.:28.71 0.098
MIN 27 4 5375.9 7.68 0.025
Table 6 MSMR Sensor Data Quality
(MSMR Sensor Data Performance from SDF)
4.1.2 ADTMS Data
There are 51 junction Temperature data available along with
SDF, which is being monitored. The routine reports are
generated for important junction temperature like Multi
frequency Feed, Sky Horn, Hot/Cold Junction and Reference
Load Junction. Initially Reference load variation was seen from
17 to 28 deg Centigrade & respective Sky Horn temperature
was seen from 12 to 23 deg Cent. Now this range of
temperature variation has been controlled for reference load
from 17 to 23 deg Centigrade (Ref: fig: 7a & 7b). The impact of
temperature variation is being observed on calibration data.
Operating temperature range is decreasing and coming close to
20° deg C with +/- 3 °C variation.
(a) 10 Deg Variation (b) 5 Deg Variation
WORTES ENGE TEE arce
A MMIAMAMO TO NOAD TASTELAT-BE VARATORUMGAR) Dias M CA NON Fr
en ALD TR ND TS r
= » t d d
M ^ d
aff M or
eo» n9 9 Hu
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= es
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wn am - 4 x xe EMO Kw wa Santo
10 Deg Variation 5 Deg Variation
x-axis: Scan number y-axis: Temperature
Fig 7 ADTMS Temperature Range
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