Scattering and attenuation of electromagnetic waves by partly charged particles

Highlights: • Attenuation of EMW due to partly charged spherical particles is analyzed based on Mie's theory. • It is found that, for EMWs of long wavelengths compared with the size of the particle, signal attenuation is generally maximal when the particle is overall charged on its surface. • The range of error due to neglecting the net charges of particle is analyzed. The scattering of electromagnetic waves (EMWs) by partly charged particles is investigated by Mie theory. For particles much smaller than the wavelength of EMW, the scattering properties are significantly affected by the net surface charges but are not affected by the location of charged area, and the extinction cross section and scattering cross section, as well as the signal attenuation due to charged particles, monotonously increase with the size of charged area and reach maximum when the particle is overall charged, as the surface charge densities is within several hundred µC/m². Moreover, given the distribution of particle sizes a closer agreement between the theory and measurement of signal attenuation due to charged sand/dust storms can be achieved by taking the charges into consideration and assuming all particles have the same size of charged area and surface charge density in theory calculations.