What is anti-reflection coating and in which application it is used?
So, anti-reflection coating is used in optics, for example, sunglasses, or lenses in microscopes to ... reduce reflections. It usually works by having a so-called thin-film on the material's surface that has a refractive index n chosen so that things that would be reflected on the air-lens interface are reflected back in a way that the way distance the reflected wave has to travel is an odd number of half wavelengths. That way, the incident wave and its reflection cancel out (interference).

For optics, that's a cool concept, and requires very accurate and fine manufacturing/coating technology, because light is in the ~800nm range, and thus, half a wavelength is very small.

The wavelengths of radio frequencies are much larger.

All antennas already work by matching their dimensions to the wavelength of the waves they want to receive or send, and not to others.

This question feels like you've been watching a documentary on nanomachines and how you can now produce little wheels in the nanometer scale, and now you're calling a car manufacturer and tell them to use this new technology called "wheel". Well, we already do.