Scattering and depolarization of microwaves by spheroidal raindrops

With a view to calculating depolarization and differential attenuation of microwaves by rain, with allowance for the variable shape and orientation of raindrops, the theory of P. C. Waterman is applied to the calculation of cross sections and depolarization ratios of spheroids, and drops of the shapes determined by H. R. Pruppacher and R. L. Pitter. Use of Waterman's extended boundary condition facilitates computation. The scattering characteristics of spheroids appear similar in nature to those of spheres, in the regimes considered. Marked singularities in the characteristics of backscattering depolarization appear at optical size 1.5. The Pruppacher and Pitter drops scatter similarly to equivalent oblate spheroids. Implications for weather radar measurements are briefly discussed.

[1]  P. Morse,et al.  Methods of theoretical physics , 1955 .

[2]  D. Jones,et al.  The Shape of Raindrops. , 1959 .

[3]  D. Atlas,et al.  Back-Scatter by Oblate Ice Spheroids , 1963 .

[4]  T. Oguchi,et al.  Attenuation of electromagnetic wave due to rain with distorted raindrops,2. , 1964 .

[5]  P. Waterman.  Matrix formulation of electromagnetic scattering , 1965 .

[6]  A. Hizal,et al.  New rigorous formulation of electromagnetic scattering from perfectly conducting bodies of arbitrary shape , 1970 .

[7]  Lotfollah Shafai,et al.  Fast generation of spherical Bessel functions with complex arguments , 1970 .

[8]  M. Plonus,et al.  The diffracted field contribution to the scattering from a large dense dielectric sphere , 1970 .

[9]  H. Pruppacher,et al.  A Semi-Empirical Determination of the Shape of Cloud and Rain Drops , 1971 .

[10]  P. Ray,et al.  Broadband complex refractive indices of ice and water. , 1972, Applied optics.

[11]  T. Oguchi.  Attenuation and phase rotation of radio waves due to rain: Calculations at 19.3 and 34.8 GHz , 1973 .

[12]  T. S. Chu,et al.  Rain-induced cross-polarization at centimeter and millimeter wavelengths , 1974 .

[13]  M. Cross,et al.  Scattering of a plane electromagnetic wave by axisymmetric raindrops , 1974 .

[14]  R. Taur,et al.  Rain depolarization measurements on a satellite-earth propagation path at 4 GHz , 1975 .

[15]  Effects of shape and orientation of spheroidal raindrops on microwave scattering , 1975 .

[16]  V. N. Bringi,et al.  Potential Use of Radar Differential Reflectivity Measurements at Orthogonal Polarizations for Measuring Precipitation , 1976 .