Title :
A procedure for measuring the coherence length of the sea texture
Author :
Conte, Ernesto ; Bisceglie, Maurizio Di ; Galdi, Carmela ; Ricci, Giuseppe
Author_Institution :
Dipt. di Ingegneria Elettronica, Naples Univ., Italy
fDate :
8/1/1997 12:00:00 AM
Abstract :
In this paper, we deal with the analysis of the temporal coherence properties of the signal backscattered from the sea surface, in the hypothesis that it can be modeled as a compound-Gaussian process. Precisely, we address the problem of measuring to what extent a compound-Gaussian process, namely the product of a nonnegative, slowly-varying modulating signal times a rapidly varying Gaussian component, can be approximated by a Gaussian process with random variance. The problem is restated in terms of a binary hypothesis test, wherein the null hypothesis of constant modulating sequence is contrasted to any alternative. The test is calibrated resorting to pseudorandom sequences and, finally, the procedure is applied to measuring the coherence length of sea data collected by scatterometers mounted on the “Forschungsplatform Nordsee” during the SAXON experiment in November 1990
Keywords :
Gaussian processes; backscatter; calibration; coherence; geophysical signal processing; oceanographic techniques; radar clutter; radar cross-sections; radar signal processing; remote sensing by radar; SAXON experiment; binary hypothesis test; coherence length; compound-Gaussian process; constant modulating sequence; nonnegative slowly-varying modulating signal; null hypothesis; pseudorandom sequences; radar clutter; random variance; scatterometers; sea data; sea surface; sea texture; signal backscatter; temporal coherence; Coherence; Gaussian processes; Length measurement; Radar measurements; Random sequences; Sea measurements; Sea surface; Signal analysis; Signal processing; Testing;
Journal_Title :
Instrumentation and Measurement, IEEE Transactions on