Will a subwavelength conductor patch reflect specularly?

[Christofer Br]

If I had metal stripe significantly longer than the wavelength but less wide than one wavelength and it would be at an angle in the plane perpendicular the length of the stripe to to the incoming wave, would itireflect specurarly or diffusely?

 

[Baluncore]

Not specular. The incident energy would excite your metal stripe resonator, which would then re-radiate the incident energy according to the radiation pattern of the metal stripe scatterer. The magnitude of excitation would be the product of the direction of energy arrival and the scatterer radiation pattern, polarisation is important.

A large field of dipoles can “glint” because all the small spherical wavefronts can reinforce to make a plane wave where the angle of incidence equals the angle of reflection.

If your scatterer is narrower than one wavelength, it could still be a half wavelength wide which would make a long linear array of resonant dipoles. That might glint in a particular direction. You need to reduce the width of the conductive stripe to below about one tenth of a wavelength to prevent glint. That is important for radar stealth design.

 

[Christofer Br]

Not specular. The incident energy would excite your metal stripe resonator, which would then re-radiate the incident energy according to the radiation pattern of the metal stripe scatterer. The magnitude of excitation would be the product of the direction of energy arrival and the scatterer radiation pattern, polarisation is important.

A large field of dipoles can “glint” because all the small spherical wavefronts can reinforce to make a plane wave where the angle of incidence equals the angle of reflection.

If your scatterer is narrower than one wavelength, it could still be a half wavelength wide which would make a long linear array of resonant dipoles. That might glint in a particular direction. You need to reduce the width of the conductive stripe to below about one tenth of a wavelength to prevent glint. That is important for radar stealth design.

What if the incoming radiation was polarized in the plane of the length of the stripe, there should be no resonance then, correct? Would such polarizsd radiation reflect specularly?