The Fiber Optics Illustrated Dictionary - Part 20 fills a gap in the literature by providing instructors, hobbyists, and top-level engineers with an accessible, current reference. From the author of the best-selling Telecommunications Illustrated Dictionary, this comprehensive reference includes fundamental physics, basic technical information for fiber splicing, installation, maintenance, and repair, and follow-up information for communications and other professionals using fiber optic components. Well-balanced, well-researched, and extensively cross-referenced, it also includes hundreds of photographs, charts, and diagrams that clarify the more complex ideas and put simpler ideas into their applications context | Fiber Optics Illustrated Dictionary circuit switching A type of end-to-end transmission system common in phone connections in the process of setting up the connection a number of resources are allocated to that specific call most of which are tied up until the call is completed and the connection terminated. One advantage of this system is that it can guarantee a certain level of performance. A disadvantage is that the resources are tied up whether or not there is active communication. See message switching packet switching. circular antenna A horizontally polarized half-wave dipole antenna formed into the shape of a circle except that the terminating ends do not touch to make a continuous loop. circular magnetic wave A magnetic wave in which the lines of force describe a circular pattern. circular polarization An electromagnetic wave whose lines of flux are oriented in a plane usually horizontal or vertical or where the edge of the field describes a circular shape. Circular polarization is used in antennas where electricity serves to uniformly rotate the electromagnetic field through the antenna. It is possible to use one circularly polarized wave to communicate with another or the circularly polarized wave can be manipulated to yield linearly polarized waves perpendicular to one another. circular scanning Scanning in which the sweep of the sensor and or the display monitor describes a full 360 arc which can be pictured as a cone shape spreading out toward the direction of the region being scanned . some types of radar . circulator 1. A process or device that moves something from hand to hand or device to device. 2. In microwave transmissions a multiterminal coupling device in which the transmission is passed down through adjacent terminals. 3. In radar transmissions a device that alternates the signal between the transmitter and the receiver. 4. In data communications a mechanism for allocating or transferring information or control among ports. CISC See .
