Microwave Data Systems EL805, Руководство по установке и эксплуатации

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MDS 05-2708A01, Rev. B MDS TransNET 900 I&O Guide G-3
Poll—A request for data issued from the host computer (or master PLC) to a
remote radio.
PLC—Programmable Logic Controller. A dedicated microprocessor
configured for a specific application with discrete inputs and outputs. It can
serve as a host or as an RTU.
Remote Radio—A radio in a spread spectrum network that communicates
with an associated master station. A radio may be programmed for either
master or remote mode using software commands.
Remote Terminal Unit—See RTU.
Repeater—A radio that receives RF data and retransmits it. See
Store-and-Forward.
RTU—Remote Terminal Unit. A data collection device installed at a remote
radio site.
SCADA—Supervisory Control And Data Acquisition. An overall term for
the functions commonly provided through an MAS radio system.
Standing Wave Ratio—See SWR.
Sub-Network—A group of TransNET transceivers and the corresponding
radio that they are directly synchronized to. A sub-network can be identified
by Extended Address. See Store-and-Forward.
Store-and-Forward—A radio that receives RF data and retransmits it. In the
TransNET product line, store and forward is defined as a network that
consists of vertically adjacent sub-networks that alternate communicating
upstream and downstream. TransNET performs store and forward at the
internal data frame level (not the the user data level) which allows TransNET
equipment to stream data with minmal latency through each
Extension/Repeater radio station.
SWR—Standing Wave Ratio. A parameter related to the ratio between
forward transmitter power and the reflected power from the antenna system.
As a general guideline, reflected power should not exceed 10% of the forward
power (
≈
2:1 SWR).Zone—See Frequency Zone.