GE MDS Master Station Technical Manual page 109

DSP—Digital Signal Processing. The transceiver's DSP is the core operating unit of the trans-
ceiver through which nearly all functions depend.
DTE—Data Terminal Equipment. A device that provides data in the form of digital signals at its
output. Connects to the DCE device.
ETH—Abbreviation for Ethernet.
Ethernet Bridging—A mode of operation for the transceiver where the radio decides whether
messages are handled locally or sent intact over-the-air.
Fade Margin—The greatest tolerable reduction in average received signal strength expected
under most conditions. Provides an allowance for reduced signal strength due to multipath fad-
ing, slight antenna movement or changing atmospheric losses. A fade margin of 20 to 30 dB is
usually sufficient in most systems.
FPGA—Field Programmable Gate Array.
Frame—A segment of data that adheres to a specific data protocol and contains definite start
and end points. It provides a method of synchronizing transmissions.
Gate—An operating mode of the transceiver with respect to diagnostic/management activities.
See also NODE, PEER, and ROOT.
Hardware Flow Control—A transceiver feature used to prevent data buffer overruns when
handling high-speed data from the RTU or PLC. When the buffer approaches overflow, the radio
drops the clear-to-send (CTS) line, which instructs the RTU or PLC to delay further transmission
until CTS again returns to the high state.
Host Computer—The computer installed at the master unit, which controls the collection of da-
ta from one or more remote sites.
I/O—Input/Output.
IP—Internet Protocol.
Intrusive Diagnostics—A mode of remote diagnostics that queries and commands radios in a
network with an impact on the delivery of the system "payload" data. See Active messaging.
LAN—Local Area Network.
LED—Light Emitting Diode.
Latency—The delay (usually expressed in milliseconds) between when data is applied to the
TXD pin at one radio, until it appears at the RXD pin of another radio.
Listen Before Transmit—A collision avoidance mechanism that attempts to allow transmission
only when the channel is clear.
mA—Milliamperes (current flow). 1000 mA = 1 Ampere.
MAC—Media Access Control.
NIC: Network Interface Card. This is another name for the modules that are selectively included
in the product based on order entry.
NX915: A GE MDS NIC module supporting unlicensed operation at 900 MHz
MAS—Multiple Address System. A radio system where a central master unit communicates
with several remote stations for the purpose of gathering telemetry data.
Master (Station)—Radio which is connected to the host computer. It is the point at which poll-
ing enters the network.
Multiple Address System—See MAS.
MDS 05-6399A01, Rev. E MDS™ Master Station 105