100
SD Series Technical Manual
MDS 05-4846A01, Rev. F
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.
DSP
—Digital Signal Processing. The transceiver’s DSP is the core
operating unit of the transceiver 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—
Ethernet
Ethernet Bridging
—A mode of operation for the SD 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 that will be anticipated under most conditions. Provides
an allowance for reduced signal strength due to multipath, 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 synchro-
nizing transmissions.
Gate
—An operating mode of the transceiver with respect to diag-
nostic/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 transmis-
sion until CTS again returns to the high state.
Host Computer
—The computer installed at the master unit, which con-
trols the collection of data from one or more remote sites.
I/O
—Input/Output
IP
—Internet Protocol
