Analysis of the Sea State Bias in Interferometric Radar Altimeter

Interferometric radar altimeter (IRA) has the ability to measure the sea surface height in wide-swath at higher resolution than conventional altimeter and is more suitable to characterize the ocean mesoscale and sub-mesoscale processes. The sea state bias (SSB) is a typical height error factor that is introduced due to the different states of sea surface waves, and is now the primary factor of height measurement error, also the focus of attention in altimeter system design and error compensation. The SSB models are different between SAR and conventional altimeter due to the difference of their working mechanism. This paper first build SAR sea state bias estimating models based on the characteristics of sea state combining SAR ocean imaging mechanism. Then the models are simulated on the different radar system parameters under typical sea states. Two different radar wavebands have been simulated including Ku band and Ka band. The relationship between SAR sea-state bias and SAR interferometry mechanism is analyzed and the simulation results are shown.