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PALS instrument

Passive Active L- and S-band Sensor

PALS is a combined polarimetric radiometer and NASA licensed radar sharing a rotating planar array antenna. The PALS instrument includes a combined L-band radiometer and scatterometer , operating at 1.413 GHz and 1.26 GHz respectively. It was designed and built to investigate the benefits of combining passive and active microwave sensors for Ocean salinity and Soil moisture remote sensing. It is the prototype for the Aquarius and SMAP missions and its' flexible design is compatible with many aircraft.

PALS has flown on the NCAR C-130, NASA’s P-3 and Twin Otter International’s, Twin Otter. It is a very mature instrument, and has flown more than 800 hours, in support of NASA campaigns.


PALS System and Antenna Dome Install on the NASA P-3B

PALS system and antenna dome
install on the NASA P-3B

PALS System and Antenna Installed on a Twin Otter

PALS system and antenna installed
on a Twin Otter

PALS Instrument Racks

PALS Instrument Racks

PALS DeploymentAircraftLocation
Very High WindsP-3Labrador Seas
SMAP Soil Moisture StudiesTwin OtterAmes, Iowa
SMAPEX-08Twin OtterDelaware
CLASIC-07Twin OtterOklahoma
Sea Salinity-03C-130Monterey, CA
Sea Salinity-01C-130Monterey, CA
Sea Salinity-99C-130Newport News, VA


Instrument Team: 

Additional Information:
SMEX02 Passive and Active L and S band System (PALS) Data