Wireless Glossary – O

Occupied BandWidth is the bandwidth containing 99% of the total integrated mean power of the transmitted spectrum on the assigned channel.

8 bits

An improvement to CDP which allows a stub router to advertise the connected IP prefix.

Orthogonal Frequency Division Multiplexing, an FDM modulation technique for transmitting large amounts of digital data over a radio wave. OFDM works by splitting the radio signal into multiple smaller sub-signals that are then transmitted simultaneously at different frequencies to the receiver. OFDM reduces the amount of crosstalk in signal transmissions. 802.11a WLAN, 802.16 and WiMAX technologies use OFDM.

Orthogonal Frequency Division Multiplexing is a method of encoding digital data on multiple carrier frequencies. OFDM has developed into a popular scheme for wideband digital communication, whether wireless or over copper wires, used in applications such as digital television and audio broadcasting, DSL broadband internet access, wireless networks, and 4G mobile communications.

Orthogonal Frequency Division Multiple Access is a multi-user version of the popular orthogonal frequency-division multiplexing (OFDM) digital modulation scheme. Multiple access is achieved in OFDMA by assigning subsets of subcarriers to individual users as shown in the illustration below. This allows simultaneous low data rate transmission from several users.

The standard unit of electrical resistance in the International System of Units (SI). Ohms are also used, when multiplied by imaginary numbers, to denote reactance in alternating-current (AC) and radio-frequency (RF) applications.

An antenna that provides a 360 degree transmission pattern. These types of antennas are used when coverage in all directions is required.

Transparent dielectric waveguide for transmitting signals using electromagnetic waves in the optical frequency range.

An instrument that measures transmission characteristics by sending a series of short pulses of light down a fiber and providing a graphic representation of the backscattered light.

An electronic device used for the purpose of generating a signal. Oscillators are found in computers, wireless receivers and transmitters, and audio-frequency equipment.

OSI, standing for Open System Interconnection, is a layered architecture model created by the International Organization for Standardization (ISO) to provide internetworking capabilities to various vendor specific networks.

This open-standard classless routing protocol applies cost as a metric. In order to minimize routing overhead, it uses areas.

Operations support system, such as a customer relationship management (CRM), billing, or provisioning system. The application programming interface (API) for Prizm supports integrating Prizm with an OSS.

Management signals that travel a dedicated channel apart from the data stream.

Method of producing optical fibers by deposition from the gas phase onto (outside vapor deposition method) the outer surface of a rotating substrate rod.

Device that enables the operator to regain control of a module that has been locked by the No Remote Access feature, the 802.3 Link Disable feature, or a password or IP address that cannot be recalled. This device can be either fabricated on site or ordered.