User's Manual

8 Mercury Reference Manual 05-4446A01, Rev. C
1.3.1 Mobile/Fixed Data System
Mercury transceivers support high-speed data communications in a
mobile environment. In this application, Remote radios “roam” between
different Access Points, providing seamless transitions and continuous
coverage throughout a municipal area.
Figure 1-3 shows an example of
an integrated system employing both mobile and fixed Mercury trans-
ceivers.
Invisible place holder
Figure 1-3. Integrated Mobile/Fixed Application
1.3.2 Wireless LAN
The wireless LAN is a common application of the transceiver. It consists
of a central control station (Access Point) and one or more associated
Remote units, as shown in
Figure 1-4. A LAN provides communications
between a central WAN/LAN and remote Ethernet segments. The oper-
ation of the radio system is transparent to the computer equipment con-
nected to the transceiver.
The Access Point is positioned at a location from which it communicates
with all Remote units in the system. Commonly, this is a high location
on top of a building or communications tower. Messages are exchanged
at the Ethernet level. This includes all types of IP traffic.
A Remote transceiver can only communicate over-the-air to an Access
Point (AP). Peer-to-peer communications between Remotes can only
take place indirectly via the AP. In the same fashion, an AP can only
communicate over-the-air to associated Remote units. Exception: Two
APs can communicate with each other “off-the-air” through their
Ethernet connectors using a common LAN/WAN.
MDS 4790
Master Radio
Licensed Serial/IP Integration
Mercury AP
MDS 4710
RTU/PL
C
(Serial
)
RS-232
RS-232
RS-232
MDS 4710
RTU/PL
C
(Serial
)
RTU/PLC
(Ethernet)
Long Range WLAN
Mobile DataMobile Data
M
DS NETview MS®
Server
(Ethernet)
Computer
Router
WAN
Video
Surveillance
Mercury
remote
Control Center
Mercury
remote
Mercury
remote
Mercury
remote