In electromagnetic wave propagation, polarization such that the tip of the electric field vector describes a helix.
Note 1: The magnitude of the electric field vector is constant.
Note 2: The projection of the tip of the electric field vector upon any fixed plane intersecting, and normal to, the direction of propagation, describes a circle.
Note 3: A circularly polarized… (Read More →)

1. A passive junction of three or more ports in which the ports can be accessed in such an order that when power is fed into any port it is transferred to the next port, the first port being counted as following the last in order.
2. In radar, a device that switches the antenna alternately between the transmitter and… (Read More →)

Cybersecurity and Infrastructure Security Agency (CISA); Emergency Communications Division (ECD) – formerly OEC (see Office of Emergency Communications)

1. The application of cryptography to television signals.
2. Television signals that have been enciphered to preserve the confidentiality of the transmitted information.

1. Of an optical fiber, one or more layers of material of lower refractive index, in intimate contact with a core material of higher refractive index.
2. A process of covering one metal with another (usually achieved by pressure rolling, extruding, drawing, or swaging) until a bond is achieved.

In the cross section of a realizable optical fiber, ideally circular, but in practice assumed to a first approximation to be elliptical, the average of the diameters of the smallest circle that can be circumscribed about the cladding, and the largest circle that can be inscribed within the cladding.

See ovality.

An undesired mode that is confined to the cladding of an optical fiber by virtue of the fact that the cladding has a higher refractive index than the surrounding medium, i.e., air or primary polymer overcoat.
Note: Modern fibers have a primary polymer overcoat with a refractive index that is slightly higher, rather than lower, than that of the cladding,… (Read More →)

In an optical fiber, anything used to convert cladding modes to radiation modes, thus removing them from the fiber.
Note: In practice, the fiber's polymer overcoat (which is also used to protect it from mechanical damage and to isolate it optically from other fibers) is used as a cladding mode stripper. The refractive index of the coating material is made… (Read More →)

See ovality.