Index - A B C D E F G H I J K L M N O P Q R S T U V W X Y Z A-Z
GAIN - Denotes an increase in signal power in transmission from one point to another; usually expressed in decibels. Antonym: " Loss ," a reduction in signal power.
GATEWAY - A conceptual, logical or physical connection between two different networks; the term implies a need for conversion of some aspect of the information or communication in order to operate through a function named a gateway. Compare to " port ," which implies a point not requiring significant conversion of the message or information.
GEOSYNCHRONOUS ORBIT - a position at an approximate altitude of 23,000 miles above the Equator, where a velocity of about 1,000 miles per hour in the same direction as Earth's rotation makes a satellite appear stationary over the Earth's surface. At such a point, ground-based microwave antennae can remain fixed and achieve linkage with transponders on board the satellite to produce a microwave relay between points as much as one-third of the way around the globe, or about 8,000 miles; this concept first proposed by British physicist and science fiction writer Arthur C. Clarke in a 1947 publication.
GRADE OF SERVICE - The probability of a call being blocked by busy trunks, expressed as a decimal fraction, and usually meaning the busy-hour probability. A common "good" grade of service figure is stated as P=.01, indicating that 99.99% of attempts will be serviced, and only 1 of 1,000 will fail. Most traffic designs are made to such a level; poor plant installation or maintenance rapidly degrades such performance.
GROUP - In analog (FDM) carrier systems, 12 telephone circuits transported as a unit. Larger units are supergroups, mastergroups, supermastergroups and jumbogroups.