WMO OSCAR | Details for Instrument WindSat

No JavaScript detected
Usage of this Website will be severly limited without JavaScript. Please enable JavaScript in your Browser.

Instrument: WindSat

Instrument details

Acronym	WindSat
Full name	WindSat
Purpose	Demonstration of sea surface wind vector observation by polarimetric passive radiometry
Short description	5 frequencies, 22-channel MW radiometer; three channels with full polarimetric capability [see detailed characteristics below]
Background	New development
Scanning Technique	Conical: 50-55° zenith angle, swath 1000 km – Scan rate: 31.6 scan/min = 12.5 km/scan
Resolution	Changing with frequency, consistent with antenna diameters of 1.83 m
Coverage / Cycle	Global in 1.5 days
Mass	307 kg	Power	311 W	Data Rate	256 kbps

Providing Agency	DoD
Instrument Maturity	Flown on an R&D satellite
Utilization Period:	2003 to 2020
Last update:	2025-04-14

Detailed characteristics

Channel number	Central frequency (GHz)	Bandwidth (MHz)	*Polarisations ()**	NEΔT	IFOV	Pixel
1	6.8	125	V, H	0.48 K	39x71 km	25.0x12.5 km
2	10.7	300	V, H, P, M, L, R	0.37 K	25x38 km	25.0x12.5 km
3	18.7	750	V, H, P, M, L, R	0.39 K	15x24 km	12.5x12.5 km
4	23.8	500	V, H	0.55 K	20x30 km	12.5x12.5 km
5	37.0	2000	V, H, P, M, L, R	0.45 K	8x13 km	6.25x12.5 km
(*) Polarisations: H = horizontal, V = vertical, P = + 45°, M = - 45°, L = left-hand circular, R = right-hand circular

Satellites this instrument is flying on

Note: a red tag indicates satellites no longer operational, a green tag indicates operational satellites, a blue tag indicates future satellites

Coriolis (DoD)
- Coriolis (see instrument status) Apr 2003 - Dec 2020

Instrument classification

Earth observation instrument
Passive microwave radiometer
Conical scanning microwave radiometer

WIGOS Subcomponents

Subcomponent 1
MW imagery [in SSO]
MW imager [in SSO]
MW imagery for surface temperature
MW imager for surface temperature

Mission objectives

Primary mission objectives

Sea surface temperature
Sea-ice cover
Wind speed (near surface)
Wind vector (near surface)

Evaluation of Measurements

The following list indicates which measurements can typically be retrieved from this category of instrument. To see a full Gap Analysis by Variable, click on the respective variable.

Note: table can be sorted by clicking on the column headers
Note: * Primary mission objective.

Search:

Variable	Relevance for measuring this variable	Operational limitations	Explanation
Snow status (wet/dry)	1 - primary	Coarse spatial resolution.	MW channels around 19 and 37 GHz with high resolution closer to the scale of snow fields
Snow water equivalent	1 - primary	Coarse spatial resolution.. Ground stations network needed.	MW channels around 19 and 37 GHz with high resolution closer to the scale of snow fields
Integrated Water Vapour (IWV)	1 - primary	No specific limitation.	Use of water vapour band around 23 GHz with dual polarisation. High resolution useful for tomography
Sea surface temperature*	2 - very high	No specific limitation.	MW channels with more frequencies around 7 and 10 GHz to reduce sensitivity to radio-frequency interferences
Sea-ice cover*	2 - very high	No specific limitation.	MW channels around 7, 10, 19 and 37 GHz, with high spatial resolution for accurate contour detection
Snow cover	2 - very high	Coarse spatial resolution.	MW channels around 19 and 37 GHz with high resolution closer to the scale of snow fields
Wind speed (near surface)*	2 - very high	Over sea only.	MW channels around 7, 10, 19 and 37 GHz
Biomass	3 - high	Index only.. Coarse spatial resolution.	Derived from differential effect of vegetation across MW frequencies around 7, 10 and 19 GHz
Cloud liquid water (CLW)	3 - high	No specific limitation.	MW channels around 37 GHz
Cloud liquid water (CLW) total column	3 - high	No specific limitation.	MW channels around 37 GHz
Long-wave Earth surface emissivity	3 - high	Long time series needed.	MW channels around 7, 10, 19 and 37 GHz. Emissivity across this MW range inferred by statistical analysis
Soil moisture at surface	3 - high	Coarse spatial resolution.. Affected by vegetation.	MW channels around 7 and 10 GHz
Wind vector (near surface)*	3 - high	Over sea only.	MW channels for 3 or 4 Stokes parameters at frequencies around 10, 19 and 37 GHz
Accumulated precipitation	4 - fair	Poor time sampling.. Time sampling to be interpolated by GEO.	MW channels around 10, 19, 23 and 37 GHz, with high spatial resolution
Precipitation intensity at surface (liquid or solid)	4 - fair	No specific limitation.	MW channels around 10, 19, 23, and 37 GHz. High spatial resolution consistent with the scale of precipitation
Soil moisture (in the roots region)	4 - fair	Coarse spatial resolution.. Affected by vegetation.	MW channels around 7 GHz. Assimilation process required
Land surface temperature	5 - marginal	Coarse spatial resolution.	MW channels with more frequencies around 7 and 10 GHz to reduce sensitivity to radio-frequency interferences
Sea-ice type	5 - marginal	No specific limitation.	MW channels around 7, 10, 19 and 37 GHz. Type interpreted as age/roughness

Showing 1 to 18 of 18 entries