Statistical modeling and simulation of delay-Doppler maps in the time-varying regime

The purpose of this paper is to extend the stationary stochastic model defined in [1] to a time evolving sea state and platform motion. The temporal analysis is carried out defining the time-varying model for the signal at the correlator output and its autocorrelation function (acf), following the work by You and Garrison [2, 3]. The temporal evolution of the signal has been integrated into the simulator developed by the Remote Sensing and Telecommunication Research Group of the University of Sannio in order to generate an arbitrary number of istantaneous correlated delay-Doppler maps. The acf function has been estimated by simulation runs and compared to known models, showing very good agreement for the signal scattered from the nominal specular point and from the other bins. The theoretical and estimated decorrelation times are about 4 ms in the nominal specular point. This result is coherent with other estimates obtained in airborne campaigns reported in [2], [4] and simulations reported in Garrison [3].