An Advection Compensation Algorithm for High-Resolution Imaging with Atmospheric Radar

An adaptive 3D imaging technique with phase compensation for atmospheric radar imaging is presented. For imaging the atmospheric structure in detail, the advection by the background wind causes phase rotation that prevents coherent integration for improving signal to noise ratio. Synthetic aperture radar (SAR) technique is one general approach to a target drifting with a known motion vector but the method requires the target to reflect waves coherently. We propose a compensation method for phase rotation caused by the advection to apply adaptive high-resolution imaging algorithms to this problem. By making correlation matrix after the phase compensation determined by measured wind velocity to received signal, an adaptive imaging such as Capon's method can be performed. This phase compensated signal, however, should be made for each points in the imaging space which takes large computation cost. To reduce the computation cost, we also introduce an approximation technique that makes the compensated signal represent certain region in the space of interest whose dimension is determined by the limit of approximation error of signal phases.