GE MDS Mercury Series User manual

Reference Manual
MDS 05-4446A01, Rev. 02
AUGUST 2008
Wireless IP/Ethernet Transceiver
Covering AP and Remote Units
DRAFT
MDS Mercury SeriesTM

05-4446A01, Rev. C Mercury Reference Manual i
TABLE OF CONTENTS
1 PRODUCT OVERVIEW AND APPLICATIONS............ 1
1.1 ABOUT THIS MANUAL.........................................................................................................3
1.1.1 Start-Up Guide ...........................................................................................................................3
1.1.2 OnlineAccess to Manuals ..........................................................................................................3
1.1.3 Conventions Used in This Manual ..............................................................................................3
1.2 PRODUCT DESCRIPTION...................................................................................................4
1.2.1 Model Offerings ..........................................................................................................................6
1.2.2 GE MDS P23 Protected Network (Redundant) Configuration ....................................................7
1.2.3 External GPS PPS Option ..........................................................................................................7
1.3 APPLICATIONS....................................................................................................................7
1.3.1 Mobile/Fixed Data System .........................................................................................................8
1.3.2 Wireless LAN ..............................................................................................................................8
1.3.3 Point-to-Point LAN Extension .....................................................................................................9
1.3.4 Serial Radio Network Connectivity .............................................................................................9
1.3.5 Multiple Protocols and/or Services ...........................................................................................10
1.3.6 Wireless LAN with Mixed Services ...........................................................................................11
1.3.7 Upgrading Older Wireless Network with Serial Interfaces ........................................................12
1.4 NETWORK DESIGN CONSIDERATIONS..........................................................................12
1.4.1 Extending Network Coverage with Repeaters ..........................................................................12
1.4.2 Protected Network Operation using MultipleAccess Points .....................................................14
1.4.3 Collocating Multiple Radio Networks ........................................................................................15
1.5 GE MDS CYBER SECURITY SUITE..................................................................................16
1.6 ACCESSORIES..................................................................................................................17
2 TABLETOP EVALUATION AND TEST SETUP....... 19
2.1 OVERVIEW.........................................................................................................................21
2.2 STEP 1 — CONNECT THE ANTENNA PORTS................................................................... 21
2.3 STEP 2 — CONNECT THE PRIMARY POWER .................................................................. 22

ii Mercury Reference Manual 05-4446A01, Rev. C
2.4 STEP 3 — CONNECT PC TO THE TRANSCEIVER............................................................23
2.5 STEP 4 — REVIEW TRANSCEIVER CONFIGURATION ....................................................23
2.5.1 Getting Started .........................................................................................................................23
2.5.2 Procedure .................................................................................................................................23
2.5.3 Basic Configuration Defaults ....................................................................................................23
2.6 STEP 5 — CONNECT LAN OR SERIAL DATA EQUIPMENT..............................................24
2.7 STEP 6 — CHECK FOR NORMAL OPERATION.................................................................26
3 EMBEDDED MANAGEMENT SYSTEM................... 29
3.1 MS INTRODUCTION..........................................................................................................31
3.1.1 Differences in the User Interfaces ............................................................................................31
3.2 ACCESSING THE MENU SYSTEM ...................................................................................33
3.2.1 Methods of Control ...................................................................................................................34
3.2.2 PC Connection and Log In Procedures ....................................................................................34
3.2.3 Navigating the Menus ...............................................................................................................38
3.3 BASIC OVERVIEW OF OPERATION.................................................................................40
3.3.1 Starting Information Screen ......................................................................................................40
3.3.2 Main Menu ................................................................................................................................42
3.4 CONFIGURING NETWORK PARAMETERS .....................................................................43
3.4.1 Network Configuration Menu ....................................................................................................43
3.4.2 Ethernet Port Configuration Menu ............................................................................................51
3.4.3 Bridge Configuration .................................................................................................................52
3.4.4 SNMPAgent Configuration .......................................................................................................53
3.4.5 AP Location Push Config Menu ................................................................................................55
3.4.6 SNTP Server Configuration ......................................................................................................57
3.5 RADIO CONFIGURATION..................................................................................................58
3.5.1 Radio Configuration Menu .......................................................................................................58
3.5.2 Serial Port Configuration ..........................................................................................................67
3.6 MODBUS / TCP SERVER CONFIGURATION ...................................................................80
3.6.1 Modbus/TCP in Mercury Transceivers
—
An Overview .............................................................80
3.6.2 Menu Selections .......................................................................................................................80
3.7 SECURITY CONFIGURATION MENU ............................................................................... 85
3.7.1 Device Security Menu ..............................................................................................................86
3.7.2 Wireless Security Menu ............................................................................................................87

05-4446A01, Rev. C Mercury Reference Manual iii
3.7.3 IEEE 802.1x DeviceAuthentication ..........................................................................................89
3.7.4 Manage Certificates .................................................................................................................91
3.8 REDUNDANCY CONFIGURATION (AP ONLY).................................................................93
3.9 GPS CONFIGURATION (REMOTE ONLY)........................................................................98
3.10 DEVICE INFORMATION MENU.....................................................................................100
3.11 PERFORMANCE INFORMATION MENU.......................................................................101
3.12 MAINTENANCE/TOOLS MENU..................................................................................... 113
3.12.1 Auto Firmware Upgrade Menu (AP Only) .............................................................................124
3.13 PERFORMANCE OPTIMIZATION..................................................................................127
3.13.1 Proper Operation — What to Look For .........................................................................129
4 TROUBLESHOOTING & RADIO
MEASUREMENTS.................................................. 133
4.1 TROUBLESHOOTING......................................................................................................135
4.1.1 Interpreting the Front Panel LEDs ..........................................................................................135
4.1.2 Troubleshooting Using the Embedded Management System ................................................136
4.1.3 Using Logged Operation Events ............................................................................................139
4.1.4 Alarm Conditions ....................................................................................................................140
4.1.5 Correcting Alarm Conditions ...................................................................................................141
4.1.6 Logged Events .......................................................................................................................142
4.2 RADIO (RF) MEASUREMENTS.......................................................................................143
4.2.1 Antenna System SWR and Transmitter Power Output ...........................................................143
4.2.2 Antenna Aiming
—
For Directional Antennas ...........................................................................144
5 PLANNING A RADIO NETWORK.......................... 147
5.1 INSTALLATION PLANNING .............................................................................................149
5.1.1 General Requirements ...........................................................................................................149
5.1.2 Site Selection .........................................................................................................................151
5.1.3 Terrain and Signal Strength ....................................................................................................151
5.1.4 Antenna & Feedline Selection ................................................................................................151
5.1.5 How Much Output Power Can be Used? ...............................................................................155
5.1.6 Conducting a Site Survey .......................................................................................................155

iv Mercury Reference Manual 05-4446A01, Rev. C
5.1.7 A Word About Radio Interference ...........................................................................................156
5.2 dBm-WATTS-VOLTS CONVERSION CHART..................................................................158
6 TECHNICAL REFERENCE..................................... 159
6.1 DATA INTERFACE CONNECTORS .................................................................................161
6.1.1 LAN Port .................................................................................................................................161
6.1.2 COM1 Port .............................................................................................................................162
6.2 SPECIFICATIONS............................................................................................................162
6.3 NOTES ON SNMP............................................................................................................165
6.3.1 Overview ................................................................................................................................165
7 GLOSSARY OF TERMS & ABBREVIATIONS....... 169
Copyright Notice
This publication is protected by U.S.A. copyright law. Copyright 2008, GE MDS. All rights
reserved.
ISO 9001 Registration
GE MDS adheres to the internationally-accepted ISO 9001 quality system standard.
To our Customers
We appreciate your patronage. You are our business. We promise to serve and anticipate your
needs. We will strive to give you solutions that are cost effective, innovative, reliable and of the
highest quality possible. We promise to build a relationship that is forthright and ethical, one that
builds confidence and trust.
Related Materials on the Internet
-
—Data sheets, frequently asked questions, case studies, applica-
tion notes, firmware upgrades and other updated information is available on the GE MDS Web site
at www.GEmds.com.
About GE MDS
Over two decades ago, GE MDS began building radios for business-critical applications. Since
then, we have installed thousands of radios in over 110 countries. To succeed, we overcame
impassable terrain, brutal operating conditions and disparate, complex network configurations. We
also became experts in wireless communication standards and system applications worldwide. The
result of our efforts is that today, thousands of utilities around the world rely on GE MDS-based
wireless networks to manage their most critical assets.

05-4446A01, Rev. C Mercury Reference Manual v
The majority of GE MDS radios deployed since 1985 are still installed and performing within our
customers’ wireless networks. That's because we design and manufacture our products in-house,
according to ISO 9001 which allows us to control and meet stringent global quality standards.
Our durable products and comprehensive solutions has made GE MDS the wireless leader in indus-
trial automation—including oil and gas production and transportation, water/wastewater treat-
ment, supply and transportation, electric transmission and distribution and many other utility
applications. GE MDS is also at the forefront of wireless communications for private and public
infrastructure and online transaction processing. Now is an exciting time for GE MDS and our cus-
tomers as we look forward to further demonstrating our abilities in new and emerging markets.
As your wireless needs change you can continue to expect more from GE MDS. We’ll always put
the performance of your network above all. Visit us at www.GEmds.com for more information.
OPERATIONAL & SAFETY NOTICES
ERP Compliance
To maintain regulatory compliance for Effective Radiated Power (ERP) of 1-Watt per MHz, the
following table of transmit power settings must be observed for the listed bandwidths and antenna
types approved. Consult the factory for other antenna options of lower gain.
CSA/
us
Notice
This product is approved for use in Class 1, Division 2, Groups A, B, C & D Hazardous Locations. Such locations are
defined in Article 500 of the National Fire Protection Association (NFPA) publication NFPA 70 , otherwise known as
the National Electrical Code.
The transceiver has been recognized for use in these hazardous locations by the Canadian Standards Association
(CSA) which also issues the US mark of approval (CSA/
US
). The CSA Certification is in accordance with CSA STD
C22.2 No. 213-M1987.
Professional installation required. The transceiver described here emits radio frequency
energy. Although the power level is low, the concentrated energy from a directional
antenna may pose a health hazard. Do not allow people to come closer than 20 cm
(7.87 inches) to the antenna when the transmitter is operating. This calculation is
based on an 18 dBi panel antenna. Additional information on RF exposure is on the
Internet at
www.fcc.gov/oet/info/documents/bulletins
.
RF Exposure

vi Mercury Reference Manual 05-4446A01, Rev. C
CSA Conditions of Approval: The transceiver is not acceptable as a stand-alone unit for use in the hazardous locations
described above. It must either be mounted within another piece of equipment which is certified for hazardous
locations, or installed within guidelines, or conditions of approval, as set forth by the approving agencies. These
conditions of approval are as follows:
The transceiver must be mounted within a separate enclosure which is suitable for the intended application.
The antenna feedline, DC power cable and interface cable must be routed through conduit in accordance with the
National Electrical Code.
Installation, operation and maintenance of the transceiver should be in accordance with the transceiver’s installation
manual, and the National Electrical Code.
Tampering or replacement with non-factory components may adversely affect the safe use of the transceiver in haz-
ardous locations, and may void the approval.
A power connector with screw-type retaining screws as supplied by GE MDS must be used.
Do not disconnect equipment unless power has been switched off or the area is known to
be non-hazardous.
Refer to Articles 500 through 502 of the National Electrical Code (NFPA 70) for further
information on hazardous locations and approved Division 2 wiring methods.
FCC Part 15 Notices
The transceiver series complies with Part 15 of the FCC Rules. Operation is subject to the following two conditions:
(1) this device may not cause harmful interference, and (2) this device must accept any interference received, including
interference that may cause undesired operation. This device is specifically designed to be used under Section 15.247
of the FCC Rules and Regulations. Any unauthorized modification or changes to this device without the express
approval of Microwave Data Systems may void the users authority to operate this device. Furthermore, the Mercury
Series is intended to be used only when installed in accordance with the instructions outlined in this manual. Failure
to comply with these instructions may also void the users authority to operate this device.
Part 15 rules also require that the Effective Isotropic Radiated Power (EIRP) from a Mercury Series installation not
exceed 36 dBm. Refer to Antenna & Feedline Selection on Page 151 for more information.
Manual Revision and Accuracy
This manual was prepared to cover a specific version of firmware code. Accordingly, some screens and features may
differ from the actual unit you are working with. While every reasonable effort has been made to ensure the accuracy
of this publication, product improvements may also result in minor differences between the manual and the product
shipped to you. If you have additional questions or need an exact specification for a product, please contact our Cus-
tomer Service Team using the information at the back of this guide. In addition, manual updates can often be found on
the GE MDS Web site at www.GEmds.com.
Environmental Information
The manufacture of this equipment has required the extraction and use of natural resources. Improper disposal may
contaminate the environment and present a health risk due to hazardous substances contained within. To avoid dissem-
ination of these substances into our environment, and to limit the demand on natural resources, we encourage you to
use the appropriate recycling systems for disposal. These systems will reuse or recycle most of the materials found in
this equipment in a sound way. Please contact GE MDS or your supplier for more information on the proper disposal
of this equipment.
EXPLOSION
HAZARD!

05-4446A01, Rev. C Mercury Reference Manual 1
1PRODUCT OVERVIEW
AND APPLICATIONS
1 Chapter Counter Reset Paragraph
Contents
1.1 ABOUT THIS MANUAL............................................................... 3
1.1.1 Start-Up Guide ..............................................................................3
1.1.2 Online Access to Manuals .............................................................3
1.1.3 Conventions Used in This Manual ................................................3
1.2 PRODUCT DESCRIPTION ......................................................... 4
1.2.1 Model Offerings .............................................................................6
1.2.2 GE MDS P23 Protected Network (Redundant) Configuration .......7
1.2.3 External GPS PPS Option .............................................................7
1.3 APPLICATIONS........................................................................... 7
1.3.1 Mobile/Fixed Data System ............................................................8
1.3.2 Wireless LAN ................................................................................8
1.3.3 Point-to-Point LAN Extension ........................................................9
1.3.4 Serial Radio Network Connectivity ................................................9
1.3.5 Multiple Protocols and/or Services ..............................................10
1.3.6 Wireless LAN with Mixed Services ..............................................11
1.3.7 Upgrading Older Wireless Network with Serial Interfaces ..........12
1.4 NETWORK DESIGN CONSIDERATIONS ................................12
1.4.1 Extending Network Coverage with Repeaters ............................12
1.4.2 Protected Network Operation using Multiple Access Points .......14
1.4.3 Collocating Multiple Radio Networks ...........................................15
1.5 GE MDS CYBER SECURITY SUITE ........................................ 16
1.6 ACCESSORIES......................................................................... 17

2 Mercury Reference Manual 05-4446A01, Rev. C

05-4446A01, Rev. C Mercury Reference Manual 3
1.1 ABOUT THIS MANUAL
This Reference Manual is one of two publications provided for users of
the Mercury SeriesTM transceiver system. It contains detailed product
information, an overview of common applications, a screen-by-screen
review of the menu system, technical specifications, suggested settings
for various scenarios, and detailed troubleshooting information. This
manual should be available to all personnel responsible for network
design, setup, commissioning and troubleshooting.
1.1.1 Start-Up Guide
The Mercury Series Start-Up Guide (Part No. 05-4558A01) is a com-
panion publication to the Reference Manual. It is a smaller book, with a
specific purpose—to guide an installer in the basic steps for getting a
transceiver on the air and communicating with other units in a network.
It provides only the essential information installers require for getting
their equipment up and running in the shortest time possible.
1.1.2 Online Access to Manuals
In addition to printed manuals, many users need access to documents
electronically. This is especially useful when you need to access docu-
mentation while traveling, or want to share a document with another
user in the field. Electronic documents also allow searching for a spe-
cific term or subject, especially in larger manuals.
Access manuals for our equipment anytime from our Web site at
www.GEmds.com. Simply click the Downloads tab at the top of the home
page and select Product Manuals from the drop-down list. A search
window appears to help you locate the manual you need.
Online manuals are provided as PDF files in the Adobe®Acrobat®stan-
dard. If necessary, download the free reader for PDF files from
www.adobe.com.
1.1.3 Conventions Used in This Manual
On-Screen Menu Items
On-screen menu items or command entries are presented in a distinctive
font to set them apart from regular text (for example: Network Name, IP
Address, Password). You will find this font most often in Chapter 3,
where the menu system is discussed in detail. When variable settings or
a range of options are available for a menu option, the items are pre-
sented inside brackets, with the default setting (if any) shown last after
a semicolon:
[available settings or range; default setting]

4 Mercury Reference Manual 05-4446A01, Rev. C
Menu Strings
To help show the path to a menu selection, navigation strings are used
in several places in this manual. For example, suppose you want to view
or set the Network Name assigned to your system. This item is located
in the Network Configuration Menu, so the navigation string in the text
would appear as shown:
Main Menu>>Network Configuration>>Network Name
By following this order of menus, you can quickly reach the desired
menu.
1.2 PRODUCT DESCRIPTION
The GE MDS Mercury SeriesTM transceiver is an easy-to-install wireless
solution offering extended range, secure operation, and multi-megabit
performance in a compact and rugged package. The transceiver is ide-
ally suited for demanding applications in fixed or mobile environments,
where reliability and range are paramount.
The transceivers are commonly used to convey text documents,
graphics, e-mail, video, Voice over IP (VoIP), and a variety of other
application data between mobile, fixed-point, and WAN/LAN-based
entities.
Based on multi-carrier Orthogonal Frequency Division Multiplexing
(OFDM), the transceiver features high speed/low latency, basic Quality
of Service (QoS) for prioritizing traffic, Ethernet and serial encapsula-
tion, and network roaming. It also provides enhanced security features
including AES encryption and IEEE 802.1x Device Authentication,
making the Mercury system the best combination of security, range, and
speed of any industrial wireless solution on the market today.
Invisible place holder
Figure 1-1. The GE MDS Mercury SeriesTM Transceiver
(Remote unit shown, AP is similar in appearance)
Rugged Packaging The transceivers are housed in a compact and rugged die cast-aluminum
case that need only be protected from direct exposure to the weather.

05-4446A01, Rev. C Mercury Reference Manual 5
This one enclosure contains all necessary components for radio opera-
tion and data communications.
Simple Installation Mercury Transceivers are designed for rapid and trouble-free installa-
tion. For basic services, you simply connect the antennas (900 MHz and
GPS, as required), connect your data equipment, apply primary power,
and set some operating parameters. No license is required for operation
in the USA, Canada, and many other countries. Check requirements for
your region before placing the equipment into service.
Most installations employ an omni-directional antenna at the Access
Point (AP) location and mobile stations. Fixed Remote stations often
employ a directional antenna aimed at the AP. Regardless of the type
used, antennas are a vital part of the system and must be chosen and
installed correctly. Refer to INSTALLATION PLANNING on
Page 149 for guidance on choosing suitable antennas and installation
sites.
Secure Operation Data network security is a vital issue in today’s wireless world. Mercury
transceivers provide multiple tools to help you build a network that min-
imizes the risk of eavesdropping and unauthorized access. Some are
inherent in the radio’s operation, such as the use of 900 MHz
spread-spectrum transmissions; others include data encryption,
enabling/disabling channels, and password protection.
Security is not a one-step process that can simply be turned on and for-
gotten. It must be practiced and enforced at multiple levels,
24 hours-a-day and 7 days-a-week. See “GE MDS CYBER SECURITY
SUITE” on Page 16 for more information about the transceiver’s secu-
rity tools.
Robust Radio
Operation The transceivers are designed for operation in the license-free 900 MHz
Industrial, Scientific, and Medical (ISM) band. They provide reliable
communications over long distances, even in the presence of weak sig-
nals or interference.
Mobile range depends on many factors, including terrain, building den-
sity, antenna gain, and speed of travel. The unit is designed for suc-
cessful application in a variety of mobile environments, and offers the
best combination of range, speed and robustness available in an indus-
trial wireless package today. By using multiple Access Points, a network
can be created that provides consistent, reliable coverage over a large
metropolitan area. See “SPECIFICATIONS” on Page 162 for more
information on transmission range.
Flexible Services Users with a mix of equipment having Ethernet and serial data interfaces
can use this equipment via a Remote transceiver. The transceiver pro-
vides services in data networks that are migrating from legacy
serial/EIA-232-based hardware to the faster and more easily interfaced
Ethernet protocol.

6 Mercury Reference Manual 05-4446A01, Rev. C
Flexible
Management You can locally or remotely configure, commission, troubleshoot, and
maintain the transceiver. Four different modes of access are available:
local RS-232 console terminal, local or remote IP access (via Telnet or
SSH), web browser (HTTP, HTTPS), and SNMP (v1/v2/v3).
The text-based interfaces (RS-232 console, Telnet, and SSH) are imple-
mented in the form of easy-to-follow menus, and the terminal server
provides a wizard to help you configure the units correctly.
Transceiver
Features The transceiver’s design makes the installation and configuration easy,
while allowing for future changes.
• Industrial-Grade Product—Extended temperature range for
trouble-free operation in extreme environments.
• Robust Radio Communications—Designed to operate over long
distances in dense, high-interference environments.
• Robust Network Security—Prevents common attack schemes
and hardware from gaining access or control of the network.
Common attack events are logged and reported by alarms.
• High Speed—1.5 Mbps is over 100-times faster than 9.6 kbps
radios.
• Plug-and-Play Connectivity—AP or Remote configuration
requires minimal setup.
• Built-in GPS Receiver—GPS technology is used for timing and
location data. The only external equipment needed for this func-
tionality is a GPS antenna (several types are available from GE
MDS).
1.2.1 Model Offerings
The transceiver comes in two primary models—Access Point and
Remote. Unique hardware is used for each model. Of the Remote radios,
there are two sub-types available—Standard Remote and Max
Remote, both of which support Ethernet and serial services. Table 1-1
summarizes each radio’s interface services.
Access Point or Remote?—Identification Tip
The outward appearance of AP and Remote radios is nearly identical,
however, the hardware for each type is different and they are not inter-
changeable. An quick way to identify them is to observe the color of the
Table 1-1. Transceiver Models and Data Interface Services
Model Sub-Type Ethernet/LAN1COM11USB Integrated WiFi
Access Point N/A Yes Yes No No
Remote Standard Remote Yes Yes No No
Max Remote Yes Yes Yes Yes
NOTES
1.COM1 provides access to the embedded Management System for all units.

05-4446A01, Rev. C Mercury Reference Manual 7
gasket seal in the center of the radio case. APs have a black gasket,
while Remote units have a yellow gasket.
In addition to gasket color, a label on the top of each radio identifies it
as an AP or Remote unit. If the label shows an –A suffix, it is an AP. If
it shows a –R suffix, it is a Remote.
1.2.2 GE MDS P23 Protected Network (Redundant)
Configuration
For mission-critical applications, a Protected Network Station is also
offered. This unit incorporates two Access Points, two power supplies,
and a switchover logic board that automatically selects between Trans-
ceiver A and Transceiver B as the active radio. Figure 1-2 shows the
protected chassis. For system-level information on this product, refer to
MDS publication 05-4161A01.
Invisible place holder
Figure 1-2. MDS P23 Protected Network Station
(incorporates two transceivers, with automatic switchover)
1.2.3 External GPS PPS Option
The External GPS Precise Positioning Service (PPS) option allows for
an external GPS device to provide the PPS input to the Mercury. This is
useful in installations where multiple radios require GPS timing. This
option prevents each Mercury from requiring its own GPS antenna.
Refer to the electrical specifications in the External GPS PPS Option
section on Page 164. This option is only available in hardware revision
1.0.2 or later.
1.3 APPLICATIONS
The following sections provide illustrations of typical transceiver instal-
lations. This is an overview only. A Network Administrator should be
involved in all installation planning activities.

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

05-4446A01, Rev. C Mercury Reference Manual 9
Invisible place holder
Figure 1-4. Typical Wireless LAN
1.3.3 Point-to-Point LAN Extension
A point-to-point configuration (Figure 1-5) is a simple arrangement
consisting of an Access Point and a Remote unit. This provides a com-
munications link for transferring data between two locations.
Invisible place holder
Figure 1-5. Typical Point-to-Point Link
1.3.4 Serial Radio Network Connectivity
The transceiver provides a path for serial devices to migrate to
IP/Ethernet systems. Many radio networks in operation today still rely
on serial networks at data rates of 9600 bps or less. These networks can
use the transceiver as a means to continue using the serial service, while
allowing the infrastructure to migrate to an IP format.
A Remote transceiver with its serial port connected to a GE MDS
serial-based radio, such as the MDS x790/x710, MDS TransNET and
others, provides a path for bringing the data from the older radio into the
IP/Ethernet environment of a Mercury-based system.
Remote
Remote
Access Point
R
emote
Remote
LAN
LAN
WAN/LAN
LAN
LAN
LAN/WAN
Access Point Remote
LAN

10 Mercury Reference Manual 05-4446A01, Rev. C
Invisible place holder
Figure 1-6. Backhaul Network
1.3.5 Multiple Protocols and/or Services
Prior to the introduction of Ethernet/IP-based radios, two radios were
often used to service two different types of devices (typically connected
to different SCADA hosts). A Mercury radio provides this capability
using a single remote unit. The unit’s serial port can be connected via IP
to different SCADA hosts, transporting different (or the same) proto-
cols. Both data streams are completely independent, and the transceiver
provides seamless simultaneous operation as shown in Figure 1-7.
Invisible place holder
Figure 1-7. Multiple Protocol Network
MDS 4790
Master
MDS 9790
Master
MDS 9810
Master
Serial Conn.
Serial Conn.
Serial Conn.
MDS 4710 Remote
N
MS Control
Point SCADA Host Modbus/IP
HUB Access Point
MDS 4710 Remote
MDS 9710 Remote
MDS 9710 Remote
MDS 9810 Remote
MDS 9810 Remote
Remote Serial
Remote Serial
Remote Serial
NETWORK
ROUTER
ROUTER Serial
Device
Serial
Device
Serial
Device
Serial
Device
Serial
Device
Serial
Device
N
ETview SCADA Host
Total Flow
Access Point
Remote Serial
Remote Serial
SCADA Host
Modbus/IP
Remote Serial
Access Point
RTU
Flow Meter
EIA-232
EIA-232
EIA-232
EIA-232
EIA-232
EIA-232
ROUTER
HUB Serial
Device
Serial
Device
Serial
Device
Serial
Device
HUB
HUB
HUB
WAN

05-4446A01, Rev. C Mercury Reference Manual 11
By using a single radio, the cost of deployment is cut in half. Beyond
requiring only one radio instead of two, the biggest cost reduction comes
from using half of the required infrastructure at the remote site: one
antenna, one feedline, one lightning protector and ancillary hardware.
Other cost reductions come from the system as a whole, such as reduced
management requirements. And above all, the radio provides the poten-
tial for future applications that run over Ethernet and IP, such as video
for remote surveillance.
1.3.6 Wireless LAN with Mixed Services
The transceiver is an excellent solution for a long-range industrial wire-
less LAN. It offers several advantages over commercial solutions, pri-
marily improved performance over extended distances. The rugged
construction of the radio and its extended temperature range make it an
ideal solution even in harsh locations. In extreme environments, a
simple NEMA enclosure is sufficient to house the unit.
The transceiver trades higher speed for longer range. Commercial
802.11a/b/g solutions are designed to provide service to relatively small
areas such as offices, warehouses and homes. They provide high data
rates but have limited range. The Mercury transmits at a higher power
level, uses a different frequency band, has higher sensitivity, and a nar-
rower channel to concentrate the radio energy, reaching farther dis-
tances. It is designed for industrial operation from the ground up.
IP-based devices that may be used with the transceiver include new,
powerful Remote Terminal Units (RTUs) and Programmable Logic
Controllers (PLCs). These, as well as other devices, may be used in
applications ranging from SCADA/telemetry monitoring, web-based
video, security monitoring, and Voice over IP. Figure 1-8 shows a typ-
ical wireless IP network.
Invisible place holder
Figure 1-8. Extended-Range LAN with Mixed Applications
N
MS Control
Point SCADA Host Modbus/IP
Access Point
Remote Bridge
Printer
IP/Ethernet
IP/Ethernet
Remote Bridge
IP/Ethernet
IP Camera

12 Mercury Reference Manual 05-4446A01, Rev. C
1.3.7 Upgrading Older Wireless Network with Serial
Interfaces
Millions of wireless data products have been installed in the last two
decades for licensed and license-free operation, many of them manufac-
tured by GE MDS. There are several ways that these systems can benefit
from incorporating Mercury equipment. The chief advantages are inter-
face flexibility (serial and Ethernet in one unit), and higher data
throughput. By taking advantage of its built-in serial and Ethernet inter-
faces, the transceiver is well suited to replace leased lines, dial-up lines,
or existing 900 MHz “multiple address” data transceivers.
Replacing Legacy Wireless Products
In most cases, legacy radio transceivers supporting serial-interface
equipment can be replaced with Mercury transceivers. Legacy equip-
ment can be connected to the transceiver through the COM1 port with a
DB-25 to DB-9 cable wired for EIA-232 signaling. The COM1 port acts
as a Data Communications Equipment (DCE) port.
NOTE: Several previous GE MDS-brand products had non-standard
signal lines on their interface connectors (for example, to
control sleep functions and alarm lines). These special func-
tions are not provided nor supported by the Mercury trans-
ceiver. Consult equipment manuals for complete pinout
information.
1.4 NETWORK DESIGN
CONSIDERATIONS
1.4.1 Extending Network Coverage with Repeaters
What is a Repeater System?
A repeater works by re-transmitting data from outlying remote sites to
the Access Point, and vice-versa. It introduces some additional
end-to-end transmission delay but provides longer-range connectivity.
In some geographical areas, obstacles can make communications diffi-
cult. These obstacles are commonly large buildings, hills, or dense
foliage. These obstacles can often be overcome with a repeater station.
Option 1—Using two transceivers to form a repeater station
(back-to-back repeater)
Although the range between fixed transceivers can be up to 40 km (25
miles) over favorable terrain, it is possible to extend the range consider-
ably by connecting two units together at one site in a “back-to-back”
fashion, creating repeater as shown in Figure 1-9. Use this arrangement
whenever the objective is to utilize the maximum range between sta-