GE MDS TransNET OEM EL806, Руководство по эксплуатации

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05-3946A01, Rev. C TransNET OEM Integration Guide 5
Point-to-Point System
A point-to-point configuration ( Figure 3 ) is a simple arrangement consisting
of just two radios—a master and a remote. This provides a half-duplex
communications link for the transfer of data between two locations.

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Figure 3. Typical Point-to-Point Link
Tail-End Link to an Existing Network
A tail-end link is often used to extend the range of a traditional (licensed)
MAS system without adding another licensed radio. This might be required
if an outlying site is blocked from the MAS master station by a natural or
man-made obstruction. In this arrangement, a spread spectrum transceiver
links the outlying remote site into the rest of the system by sending data from
that site to an associated transceiver installed at one of the licensed remote
sites—usually the one closest to the outlying facility. (See
Figure 4 ).
As the data from the outlying site is received at the associated transceiver, it
is transferred to the co-located licensed radio (via a data crossover cable) and
is transmitted to the MAS master station over the licensed channel. Addi-
tional details for tail-end links are given in Section
6.2 ( Page 19 ).
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Figure 4. Typical Tail-End Link Arrangement
Master Site Remote Site
Host System
DATA
TRANSCEIVER
DATA
TRANSCEIVER
REPEATER STATION
Remote Radio
ENTER
ESCAPE
ACTIVE
ACTIVE
STBY ALARM
RX ALR
TX ALR
STBY ALARM
RX ALR TX ALR
LINE
LINE
Null-Modem Cable
Remote
Radio
Remote
Radio
Master Station
SPREAD SPECTR
UM LINK
TO
OUTL
YING SITE
OUTLYING
REMOTE SITE
MAS SYSTEM (LICENSED OR UNLICENSED) LICENSE-FREE SPREAD SPECTRUM SYSTEM
RTU
RTU
RTU
DATA
TRANSCEIVER
DATA
TRANSCEIVER