Monostatic lidar/radar invisibility using coated spheres.
The Lorenz-Mie theory is revisited to explicitly include materials whose permeability is different from unity. The expansion coefficients of the scattered field are given for light scattering by both homogeneous and coated spheres. It is shown that the backscatter is exactly zero if the impedance of the spherical particles is equal to the intrinsic impedance of the surrounding medium. If spherical particles are sufficiently large, the zero backscatter can be explained as impedance matching using the asymptotic expression for the radar backscattering cross section. In the case of a coated sphere, the shell can be regarded as a cloak if the product of the thickness and the imaginary part of the refractive index of the outer shell is large.
1Department of Physics, Texas A&M University, College Station, TX, 77843, USA. pwzhai@tamu.edu
Peng-Wang
PW
Zhai
Yu
Y
You
George W
GW
Kattawar
Ping
P
Yang
D004867:Equipment Design; D019544:Equipment Failure Analysis; D005336:Fiber Optic Technology / Q000295:instrumentation*; D007834:Lasers; D008863:Microspheres; D011825:Radar / Q000295:instrumentation*; D012637:Security Measures; D012822:Silicon Dioxide
D012822:Silicon Dioxide