Angular momentum radio techniques

Present-day state-of-the-art radio science and wireless radio communication techniques are almost exclusively based on the simple physical mechanism by which radiation is generated and detected by a one-dimensional (scalar) oscillating current modulated with information. This approach has the unavoidable fundamental physical limitation that it only utilizes the translational degrees of freedom of the EM field. The physical observables that describe these translational degrees of freedom are the mechanical linear momentum of the charged particles (also known as the charge degree of freedom), p^mech, and the associated EM linear momentum (the volume integrated Poynting vector), p^field. The inherently single-state vectorial observable p^field can propagate in free space to a remotely located receiving antenna where the reverse linear momentum exchange process takes place, allowing the information encoded onto p^field to be extracted from the induced mechanical momentum of the charges, i.e. the receiving antenna current.