IEEE Geoscience and Remote Sensing Magazine - December 2016 - 40
TABLE 1. THE KEY FEATURES OF SATELLITE WIND SCATTEROmETERS [20].
PARAmETER
SASS
AmI SCAT
NSCAT
SEAWINDS
ASCAT
OSCAT
FreQUencY
14.6 GHz
5.3 GHz
13.995 GHz
13.4 GHz
5.3 GHz
13.5 GHz
PoLarization
V-H, V-H
V only
V, V-H V
V-outer/H-inner
V only
V-outer/H-inner
Beam resoLUtion
Fixed doppler
range gate
Variable doppler
Pencil beam
range gate
Pencil beam
science modes
many
sar, wind
Wind only
Wind/hi-res
Wind only
Wind/hi-res
resoLUtion
nominally 50 km
50 km
25 km
egg: 25 × 35 km
slice: 6 × 25 km
25/50 km
egg: 30 × 68 km
slice: 6 × 30 km
500
1,400
antenna
azimUtHs
sWatH, km
~750
~750
500
600
600
1,400
1,800
500
1,836
incidence anGLes
0-70°
18-59°
17-60°
46 and 54.4°
25-65°
49 and 57°
daiLY coVeraGe
Variable
< 41%
78%
92%
65%
> 90%
ers-1: 3/92-1/01
ers-2: 4/95-9/11
adeos-i:
8/96-6/97
Quikscat: 6/99-11/09
adeos-ii: 1/02-10/02
metop-a: 6/07-present
metop-B: 4/09-present
oceansat-2:
10/09-present
mission and dates seasat:
6/78-10/78
pulses by the small waves on the water surface [2]. At that
time, such backscatter represented nothing more than
a disturbance, making the identification of ships more
difficult and less reliable. As time passed, an awareness
that such a disturbance could also represent a source of
additional information started to emerge. For the last 50
years, microwave scatterometers on aircraft and satellites
have indeed proven their effectiveness in studying the
water-surface backscattering
signatures and in measuring
the wind vector over water.
FOR REMOTE STUdY
The idea of spaceborne scatOF A MICROWAVE
terometers was hatched with
bACKSCATTERInG
the advent of satellites, moSIGnATURE OF ThE WATER
tivated by difficulties in the
location of a huge number of
SURFACE FROM AIRCRAFT,
meteorological instruments
AIRbORnE SCATTEROMETERS
in the ocean. The first spaceARE USEd.
borne scatterometer was a
combined radiometer/scatterometer (RADSCAT) operated as a part of the Skylab experiment flown in 1973
[17]. Before then, a number of airborne and platform scatterometer experiments had to be performed in advance
to study water-surface backscattering properties; to determine their dependence on incidence and azimuth angles,
frequency, polarization, and wind speed and direction [9],
[17]-[19]; and to develop appropriate geophysical model
functions for wind retrieval.
The measurement geometry is a very important factor in the wind-retrieval process. Two approaches are
40
commonly used to collect multiple measurements of the
water-surface NRCS from different azimuth directions:
1) a multifan-beam antenna geometry and 2) a pencilbeam rotating antenna geometry. On satellites, the multifan-beam geometry has been used, for example, for the
European scatterometers on the European Remote Sensing Satellites (ERS)-1 and ERS-2 [advanced microwave
instrument (AMI) scatterometers], the meteorological
operational satellites MetOp-A and MetOp-B [advanced
scatterometers (ASCAT)-A and ASCAT-B], and for the
NASA scatterometers on the seafaring satellite SeaSat-A
[SeaSat-A scatterometer system (SASS)] and the Advanced
Earth Observing Satellite (ADEOS) [NASA scatterometer
(NSCAT)]. A disadvantage of the traditional satellite fanbeam scatterometer designs is the nadir gap between right
and left swaths. Therefore, newer designs of the pencilbeam rotating antenna geometry have been used for other
scatterometers mounted, e.g., at the NASA scatterometer
satellite QuikSCAT (SeaWinds scatterometer), the Indian
Oceansat-2 [Oceansat-2 scatterometer (OSCAT)], and the
Chinese HY-2A [Ku-band rotating fan-beam scatterometer
(KU-RFSCAT)]. The key features of several satellite wind
scatterometers are presented in Table 1.
For remote study of a microwave backscattering signature of the water surface from aircraft, airborne scatterometers are used. Measurements are typically performed at
either a circular track flight using a fixed fan-beam antenna
(Figure 1) or a rectilinear track flight using a rotating antenna (Figure 2) [6], [7], [9], [21]-[23]. An overview of some
airborne scatterometers is presented in Table 2. A detailed
overview of airborne and spaceborne missions, equipment,
ieee Geoscience and remote sensinG maGazine
DECEmBER 2016
Table of Contents for the Digital Edition of IEEE Geoscience and Remote Sensing Magazine - December 2016
IEEE Geoscience and Remote Sensing Magazine - December 2016 - Cover1
IEEE Geoscience and Remote Sensing Magazine - December 2016 - Cover2
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 1
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 2
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 3
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 4
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 5
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 6
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 7
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 8
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 9
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 10
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 11
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 12
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 13
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 14
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 15
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 16
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 17
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 18
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 19
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 20
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 21
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 22
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 23
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 24
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 25
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 26
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 27
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 28
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 29
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 30
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 31
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 32
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 33
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 34
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 35
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 36
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 37
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 38
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 39
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 40
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 41
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 42
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 43
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 44
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 45
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 46
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 47
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 48
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 49
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 50
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 51
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 52
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 53
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 54
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 55
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 56
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 57
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 58
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 59
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 60
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 61
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 62
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 63
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 64
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 65
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 66
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 67
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 68
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 69
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 70
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 71
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 72
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 73
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 74
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 75
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 76
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 77
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 78
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 79
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 80
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 81
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 82
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 83
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 84
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 85
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 86
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 87
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 88
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 89
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 90
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 91
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 92
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 93
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 94
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 95
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 96
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 97
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 98
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 99
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 100
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 101
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 102
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 103
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 104
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 105
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 106
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 107
IEEE Geoscience and Remote Sensing Magazine - December 2016 - 108
IEEE Geoscience and Remote Sensing Magazine - December 2016 - Cover3
IEEE Geoscience and Remote Sensing Magazine - December 2016 - Cover4
https://www.nxtbook.com/nxtbooks/ieee/geoscience_december2023
https://www.nxtbook.com/nxtbooks/ieee/geoscience_september2023
https://www.nxtbook.com/nxtbooks/ieee/geoscience_june2023
https://www.nxtbook.com/nxtbooks/ieee/geoscience_march2023
https://www.nxtbook.com/nxtbooks/ieee/geoscience_december2022
https://www.nxtbook.com/nxtbooks/ieee/geoscience_september2022
https://www.nxtbook.com/nxtbooks/ieee/geoscience_june2022
https://www.nxtbook.com/nxtbooks/ieee/geoscience_march2022
https://www.nxtbook.com/nxtbooks/ieee/geoscience_december2021
https://www.nxtbook.com/nxtbooks/ieee/geoscience_september2021
https://www.nxtbook.com/nxtbooks/ieee/geoscience_june2021
https://www.nxtbook.com/nxtbooks/ieee/geoscience_march2021
https://www.nxtbook.com/nxtbooks/ieee/geoscience_december2020
https://www.nxtbook.com/nxtbooks/ieee/geoscience_september2020
https://www.nxtbook.com/nxtbooks/ieee/geoscience_june2020
https://www.nxtbook.com/nxtbooks/ieee/geoscience_march2020
https://www.nxtbook.com/nxtbooks/ieee/geoscience_december2019
https://www.nxtbook.com/nxtbooks/ieee/geoscience_september2019
https://www.nxtbook.com/nxtbooks/ieee/geoscience_june2019
https://www.nxtbook.com/nxtbooks/ieee/geoscience_march2019
https://www.nxtbook.com/nxtbooks/ieee/geoscience_december2018
https://www.nxtbook.com/nxtbooks/ieee/geoscience_september2018
https://www.nxtbook.com/nxtbooks/ieee/geoscience_june2018
https://www.nxtbook.com/nxtbooks/ieee/geoscience_march2018
https://www.nxtbook.com/nxtbooks/ieee/geoscience_december2017
https://www.nxtbook.com/nxtbooks/ieee/geoscience_september2017
https://www.nxtbook.com/nxtbooks/ieee/geoscience_june2017
https://www.nxtbook.com/nxtbooks/ieee/geoscience_march2017
https://www.nxtbook.com/nxtbooks/ieee/geoscience_december2016
https://www.nxtbook.com/nxtbooks/ieee/geoscience_september2016
https://www.nxtbook.com/nxtbooks/ieee/geoscience_june2016
https://www.nxtbook.com/nxtbooks/ieee/geoscience_march2016
https://www.nxtbook.com/nxtbooks/ieee/geoscience_december2015
https://www.nxtbook.com/nxtbooks/ieee/geoscience_september2015
https://www.nxtbook.com/nxtbooks/ieee/geoscience_june2015
https://www.nxtbook.com/nxtbooks/ieee/geoscience_march2015
https://www.nxtbook.com/nxtbooks/ieee/geoscience_december2014
https://www.nxtbook.com/nxtbooks/ieee/geoscience_september2014
https://www.nxtbook.com/nxtbooks/ieee/geoscience_june2014
https://www.nxtbook.com/nxtbooks/ieee/geoscience_march2014
https://www.nxtbook.com/nxtbooks/ieee/geoscience_december2013
https://www.nxtbook.com/nxtbooks/ieee/geoscience_september2013
https://www.nxtbook.com/nxtbooks/ieee/geoscience_june2013
https://www.nxtbook.com/nxtbooks/ieee/geoscience_march2013
https://www.nxtbookmedia.com