• Journal of the Korean Society for Marine Environment & Energy
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• v.15 no.3
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• pp.208-218
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• 2012

Numerical simulation technique has been developed to calculate microwave backscattering from water surface. The simulation plays a role of a substitute for experiments. Validation of the simulation was shown by comparing with experimental results. Water area observations by microwave radar have been simulated to evaluate algorithms and systems. Furthermore, the simulation can be used to understand microwave scattering mechanism on the water surface. The simulation has applied to the various methods for water area observations, and the utilizations of the simulation are introduced in this paper. In the case of fixed radar, we show following examples, 1. Radar image with a pulse Doppler radar, 2. Effect of microwave irradiation width and 3. River observation (Water level observation). In addition, another application (4.Synthetic aperture radar image) is also described. The details of the applications are as follows. 1. Radar image with a pulse Doppler radar: A new system for the sea surface observation is suggested by the simulation. A pulse Doppler radar is assumed to obtain radar images that display amplitude and frequency modulation of backscattered microwaves. The simulation results show that the radar images of the frequency modulation is useful to measure sea surface waves. 2. Effect of microwave irradiation width: It is reported (Rheem[2008]) that microwave irradiation width on the sea surface affects Doppler spectra measured by a CW (Continuous wave) Doppler radar. Therefore the relation between the microwave irradiation width and the Doppler spectra is evaluated numerically. We have shown the suitable condition for wave height estimation by a Doppler radar. 3. River observation (Water level observation): We have also evaluated algorithms to estimate water current and water level of river. The same algorithms to estimate sea surface current and sea surface level are applied to the river observation. The simulation is conducted to confirm the accuracy of the river observation by using a pulse Doppler radar. 4. Synthetic aperture radar (SAR) image: SAR images are helpful to observe the global sea surface. However, imaging mechanisms are complicated and validation of analytical algorithms by SAR images is quite difficult. In order to deal with the problems, SAR images in oceanic scenes are simulated.