- 行业: Telecommunications
- Number of terms: 29235
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ATIS is the leading technical planning and standards development organization committed to the rapid development of global, market-driven standards for the information, entertainment and communications industry.
In an optical communications link, the difference between (a) the optical power that is launched by a given transmitter into the fiber, less transmission losses from all causes, and (b) the minimum optical power that is required by the receiver for a specified level of performance. Note 1: The optical power margin is usually expressed in dB. At least several dB of optical power margin should be included in the optical power budget. Note 2: The amount of optical power launched into a given fiber by a given transmitter depends on the nature of its active optical source (LED or laser diode) and the type of fiber, including such parameters as core diameter and numerical aperture.
Industry:Telecommunications
In an optical communications link, phase jitter of the signal caused by the combined effects of mode hopping in the optical source and intramodal distortion in the fiber. Note: Mode hopping causes random wavelength changes which in turn affect the group velocity, i.e., the propagation time. Over a long length of fiber, the cumulative effect is to create jitter, i.e., mode partition noise. The variation of group velocity creates the mode partition noise.
Industry:Telecommunications
In an optical communication system, an optoelectronic device or module that receives an optical signal, amplifies it (or, in the case of a digital signal, reshapes, retimes, or otherwise reconstructs it,) and retransmits it as an optical signal.
Industry:Telecommunications
In alternating-current power transmission and distribution, the product of the rms voltage and amperage, i.e., the apparent power, multiplied by the power factor, i.e., the cosine of the phase angle between the voltage and the current. Note: Only effective power, i.e., the actual power delivered to or consumed by the load, is expressed in watts. Apparent power is properly expressed only in volt-amperes, never watts. Synonym true power. See figure by clicking on the "Pict" icon below.
Industry:Telecommunications
In an optical communication link, noise attributable to the statistical nature of optical quanta. See quantum noise.
Industry:Telecommunications
In an open waveguide, such as an optical fiber, a loss of energy on the part of an electromagnetic wave due to obstacles outside the waveguide, abrupt changes in direction of the waveguide, or other anomalies, that cause changes in the propagation mode of the wave in the waveguide.
Industry:Telecommunications
In an internet, a service protocol that is used (by routers, but not by hosts) to maintain routing tables; routing protocols are classified as either (a) interior gateway protocols, or (b) exterior gateway protocols.
Industry:Telecommunications
In an Internet Protocol (IP) address, an extension that allows users in a network to use a single IP network address for multiple physical subnetworks. Note: The IP address contains three parts: the network, the subnet, and host addresses. Inside the subnetwork, gateways and hosts divide the local portion of the IP address into a subnet address and a host address. Outside of the subnetwork, routing continues as usual by dividing the destination address into a network portion and a local portion.
Industry:Telecommunications
In an integrated services digital network, (ISDN,) a method of transmitting, multiplexing, and switching.
Industry:Telecommunications
In an Integrated Services Digital Network (ISDN,) the portion of the ISDN access that a network provider supplies to connect the customer, i.e., subscriber, installation to the network. Note: Customer access includes those network elements or portions of elements that extend from the access switch to the network interface.
Industry:Telecommunications
