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Sea Surface Wind Speed (GPS-R Winds)


Operated By: 

Estimation of surface wind speed by matching the shape of the reflected GPS signal correlation function against analytical models. Wind speed obtained from this method has agreed with that recorded from buoys with a bias of less than 0.1 m/s, and with a standard deviation of 1.3 m/s.

A modified GPS receiver is used to track the direct line of sight satellites through a zenith-oriented right hand circularly polarized (RHCP) antenna and record the cross-correlation function of the reflected signals using a nadir-oriented left hand circularly polarized (LHCP) antenna. The cross-correlation for one or two satellites is continuously recorded in 10 to 12 range bins. Accumulation is done in hardware for an integration time of 1 ms. Batches of 0.1 seconds of the sum square of the inphase and quadrature components are then averaged before being saved to disk.

Instrument Type: 
Point(s) of Contact: 
Jim Garrison (POC; PI)