Glossary Of Terms & Abbreviations - GE MDS Master Station Technical Manual

9.0 GLOSSARY OF TERMS & ABBREVIATIONS
If you are new to wireless data systems, some of the terms in this guide may be unfamiliar. The
following glossary explains many of these terms and can prove helpful in understanding the op-
eration of the Master Station. While some entries may not appear specifically in the text of this
manual, they are included to promote a more complete understanding of wireless data networks,
both of current and legacy design.
Active Messaging—This is a mode of diagnostic gathering that may interrupt payload system
polling communications (contrast with passive messaging). Active (or intrusive) messaging is
faster than passive messaging because it is not dependent upon the RTU polling cycle.
Antenna System Gain—A figure, normally expressed in dB, representing the power increase
resulting from the use of a gain-type antenna. System losses (from the feedline and coaxial con-
nectors, for example) are subtracted from this figure to calculate the total antenna system gain.
BER—Bit Error Rate.
Bit—The smallest unit of digital data, often represented by a one or a zero. Eight bits (plus start,
stop, and parity bits) usually comprise a byte.
Bits-per-second—See BPS.
BPS—Bits-per-second. A measure of the information transfer rate of digital data across a com-
munication channel.
Bridging—(see Ethernet Bridging).
Byte—A string of digital data usually made up of eight data bits and start, stop and parity bits.
Ckeyed—Pertains to continuously keyed Master stations (full-duplex).
CLI—Command Line Interface. A method of user control where commands are entered as
character strings to set configuration and operating parameters.
CTS—Clear to Send.
Decibel (dB)—A measure computed from the ratio between two signal levels. Frequently used
to express the gain (or loss) of a system.
Data Circuit-terminating Equipment—See DCE.
Data Communications Equipment—See DCE.
Data Terminal Equipment—See DTE.
dBi—Decibels referenced to an "ideal" isotropic radiator in free space. Frequently used to ex-
press antenna gain.
dBm—Decibels referenced to one milliwatt. An absolute unit used to measure signal power, as
in transmitter power output, or received signal strength.
DCE—Data Circuit-terminating Equipment (or Data Communications Equipment). In data
communications terminology, this is the "modem" side of a computer-to-modem connection.
The transceiver described in this manual is hardwired as a DCE device.
Digital Signal Processing—See DSP.
DLINK—Data Link Mode. This is a GE MDS-proprietary protocol used when the transceiver is
in diagnostics mode.
104 MDS™ Master Station MDS 05-6399A01, Rev. E