(under subclass 700) Subject matter wherein a conductive or low reluctance structure, such as a wire, plate, or grid, is combined with the antenna to reduce, as by dissipation through a resistance or by conduction to ground, undesired radiation, or electric or magnetic fields, which are directed toward the antenna from an external source, or which emanate from the antenna.
(1) Note. While a shield may modify the radiation of an antenna as does the reflector, in the case of the shield the energy is essentially absorbed rather than returned to space. Likewise in the case of the ground, as in subclass 846 below, the reflecting function may also be performed.
(2) Note. For classification in this subclass, the shield must cooperate with the antenna in its operative position. A mere sheath for an antenna when not in use is not classified in this subclass, but in subclasses 872 and 889.
SEE OR SEARCH THIS CLASS, SUBCLASS:
702, for antennas combined with radio cabinets which may include shielding.
705+, 709+ and 711+, for antennas with aircraft, watercraft and vehicle structure respectively, where the antennas may be shielded by such structure.
719, for antennas buried underground or submerged under water. 829, for fractional, multiple or full wave linear type antennas with a decoupling shield.
851, for antennas with a coupling network or impedance in the leadin, together with a shield for such network or impedance.
872, for antennas with a housing or protective covering.
905, for antennas combined with shielded transmission lines.
906, for antennas combined with shielded electrical connectors.
SEE OR SEARCH CLASS
174, Electricity: Conductors and Insulators,
35+, for shielded or screened electrical conductors and insulators.
307, Electrical Transmission or Interconnection Systems,
91, for electrical transmission systems with shielding means, generally.
455, Telecommunications, 271, and 283+ for radiation prevention and noise elimination in the antenna circuits of radio receivers.
