Re:Is this better? (Score 1)

Radio waves require a larger device to focus them than light waves (or infrared) because they have a much longer wavelength. For example, to produce a beam of 1 degree width in the UHF band (about 400 megahertz) you need a radio dish 50 meters across. The wireless "line of sight" links also require some space around the beam clear of obstructions.