October 2013
Version 1.6.2
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Aprisa SR User Manual
Copyright
Copyright © 2013 4RF Limited. All rights reserved.
This document is protected by copyright belonging to 4RF Limited and may not be reproduced or
republished in whole or part in any form without the prior written permission of 4RF Limited.
Trademarks
Aprisa and the 4RF logo are trademarks of 4RF Limited.
Windows is a registered trademark of Microsoft Corporation in the United States and other countries. Java
and all Java-related trademarks are trademarks or registered trademarks of Sun Microsystems, Inc. in the
United States and other countries. All other marks are the property of their respective owners.
Disclaimer
Although every precaution has been taken preparing this information, 4RF Limited assumes no liability for
errors and omissions, or any damages resulting from use of this information. This document or the
equipment may change, without notice, in the interests of improving the product.
RoHS and WEEE Compliance
The Aprisa SR is fully compliant with the European Commission’s RoHS (Restriction of Certain Hazardous
Substances in Electrical and Electronic Equipment) and WEEE (Waste Electrical and Electronic Equipment)
environmental directives.
Restriction of hazardous substances (RoHS)
The RoHS Directive prohibits the sale in the European Union of electronic equipment containing these
hazardous substances: lead, cadmium, mercury, hexavalent chromium, polybrominated biphenyls (PBBs),
and polybrominated diphenyl ethers (PBDEs).
4RF has worked with its component suppliers to ensure compliance with the RoHS Directive which came
into effect on the 1st July 2006.
End-of-life recycling programme (WEEE)
The WEEE Directive concerns the recovery, reuse, and recycling of electronic and electrical equipment.
Under the Directive, used equipment must be marked, collected separately, and disposed of properly.
4RF has instigated a programme to manage the reuse, recycling, and recovery of waste in an
environmentally safe manner using processes that comply with the WEEE Directive (EU Waste Electrical
and Electronic Equipment 2002/96/EC).
4RF invites questions from customers and partners on its environmental programmes and compliance with
the European Commission’s Directives (sales@4RF.com).
2 |
Aprisa SR User Manual
12.5 kHz Channel
25 kHz Channel
Radio performance
EN 300 113-2
EN 302 561
EMC
EN 301 489 Parts 1 & 5
Environmental
EN 300 019, Class 3.4
Safety
EN 60950-1:2006
Frequency band
Channel size
Power input
Notified
body
136-174 MHz
12.5 kHz, 25 kHz
12 VDC
400-470 MHz
12.5 kHz, 25 kHz
12 VDC
Compliance General
The Aprisa SR digital radio predominantly operates within frequency bands that require a site license be
issued by the radio regulatory authority with jurisdiction over the territory in which the equipment is
being operated.
It is the responsibility of the user, before operating the equipment, to ensure that where required the
appropriate license has been granted and all conditions attendant to that license have been met.
Changes or modifications not approved by the party responsible for compliance could void the user’s
authority to operate the equipment.
Equipment authorizations sought by 4RF are based on the Aprisa SR radio equipment being installed at a
fixed restricted access location and operated in point-to-multipoint or point-to-point mode within the
environmental profile defined by EN 300 019, Class 3.4. Operation outside these criteria may invalidate
the authorizations and / or license conditions.
The term ‘Radio’ with reference to the Aprisa SR User Manual, is a generic term for one end station of a
point-to-multipoint Aprisa SR network and does not confer any rights to connect to any public network or
to operate the equipment within any territory.
Compliance European Telecommunications Standards Institute
The Aprisa SR radio is designed to comply with the European Telecommunications Standards Institute
(ETSI) specifications as follows:
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Aprisa SR User Manual
Radio performance / EMC
47CFR part 90 Private Land Mobile Radio Services
47CFR part 15 Radio Frequency Devices
Safety
EN 60950-1:2006
Frequency band
limits
Channel
size
Power
input
Authorization
FCC ID
406.1 to 454.0 MHz
456.0 to 470.0 MHz
12.5 kHz
12 VDC
Part 90 Certification
UIPSRN0400012A
Radio performance
RSS-GEN
RSS-119
EMC
This Class A digital apparatus complies with Canadian
standard ICES-003.
Cet appareil numérique de la classe A est conforme à
la norme NMB-003 du Canada.
Safety
EN 60950-1:2006
Frequency band
limits
Channel
size
Power
input
Authorization
IC ID
406.1 to 430.0 MHz
450.0 to 470.0 MHz
12.5 kHz,
25 kHz
12 VDC
RSS-119
6772A-SRN400
Compliance Federal Communications Commission
The Aprisa SR radio is designed to comply with the Federal Communications Commission (FCC)
specifications as follows:
NOTE: This equipment has been tested and found to comply with the limits for a Class A digital device,
pursuant to part 15 of the FCC Rules. These limits are designed to provide reasonable protection against
harmful interference when the equipment is operated in a commercial environment. This equipment
generates, uses, and can radiate radio frequency energy and, if not installed and used in accordance with
the instruction manual, may cause harmful interference to radio communications. Operation of this
equipment in a residential area is likely to cause harmful interference in which case the user will be
required to correct the interference at his own expense.
Compliance Industry Canada
The Aprisa SR radio is designed to comply with Industry Canada (IC) specifications as follows:
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Aprisa SR User Manual
Compliance Hazardous Locations Notice
This product is suitable for use in Class 1, Division 2, Groups A - D hazardous locations or non-hazardous
locations.
WARNING - EXPLOSION HAZARD - DO NOT REPLACE FUSE UNLESS POWER HAS BEEN SWITCHED OFF OR THE
AREA IS KNOWN TO BE NON-HAZARDOUS.
AVERTISSEMENT - RISQUE D'EXPLOSION - COUPER LE COURANT OU S'ASSURER QUE L'EMPLACEMENT EST
DESIGNE NON DANGEREUX AVANT DE REPLACER LE FUSIBLE.
WARNING - EXPLOSION HAZARD - DO NOT DISCONNECT EQUIPMENT UNLESS POWER HAS BEEN SWITCHED
OFF OR THE AREA IS KNOWN TO BE NON-HAZARDOUS.
AVERTISSEMENT - RISQUE D'EXPLOSION - AVANT DE DECONNECTER L'EQUIPEMENT, COUPER LE COURANT OU
S'ASSURER QUE L'EMPLACEMENT EST DESIGNE NON DANGEREUX.
Protection switch remote control connection diagram for hazardous locations.
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Aprisa SR User Manual
WARNING:
The installer and / or user of Aprisa SR radios shall ensure that a separation distance
as given in the following table is maintained between the main axis of the terminal’s
antenna and the body of the user or nearby persons.
Minimum separation distances given are based on the maximum values of the
following methodologies:
1. Maximum Permissible Exposure non-occupational limit (B or general public) of
47 CFR 1.1310 and the methodology of FCC’s OST/OET Bulletin number 65.
2. Reference levels as given in Annex III, European Directive on the limitation of
exposure of the general public to electromagnetic fields (0 Hz to 300 GHz)
(1999/519/EC). These distances will ensure indirect compliance with the
requirements of EN 50385:2002.
Frequency (MHz)
Maximum Power
(dBm)
Maximum Antenna
Gain (dBi)
Minimum Separation
Distance
(m)
136
+ 37
15
2.5
174
+ 37
15
2.5
330
+ 37
15
2.5
400
+ 37
15
2.5
470
+ 37
15
2.3
RF Exposure Warning
Contents | 7
Aprisa SR User Manual
Contents
1. Getting Started ........................................................................ 13
2. Introduction ............................................................................ 15
About This Manual ............................................................................... 15
What It Covers ............................................................................ 15
Who Should Read It ...................................................................... 15
Contact Us ................................................................................. 15
What’s in the Box ............................................................................... 15
Aprisa SR Accessory Kit .................................................................. 16
Aprisa SR CD Contents ................................................................... 16
Software ............................................................................ 16
Documentation .................................................................... 16
3. About the Radio ....................................................................... 17
The 4RF Aprisa SR Radio ........................................................................ 17
Product Overview ............................................................................... 18
Network Coverage and Capacity ....................................................... 18
Remote Messaging ........................................................................ 18
Repeater Messaging ...................................................................... 19
Product Features ................................................................................ 20
Functions .................................................................................. 20
Performance .............................................................................. 20
Usability ................................................................................... 20
Architecture ............................................................................... 21
Product Operation ................................................................. 21
Physical Layer ............................................................................. 21
Data Link Layer / MAC layer ............................................................ 21
Channel Access .................................................................... 21
Hop by Hop Transmission ......................................................... 22
Network Layer ............................................................................ 23
Packet Routing ..................................................................... 23
Security ........................................................................................... 24
Interfaces ......................................................................................... 25
Antenna Interface ........................................................................ 25
Ethernet Interface ....................................................................... 25
RS-232 Interface .......................................................................... 25
USB Interfaces ............................................................................ 25
Alarms ...................................................................................... 25
Front Panel Connections ....................................................................... 26
LED Display Panel ............................................................................... 27
Normal Operation ........................................................................ 27
Single Radio Software Upgrade ......................................................... 27
Network Software Upgrade ............................................................. 28
Test Mode ................................................................................. 28
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Aprisa SR User Manual
4. Product Options ....................................................................... 29
Dual Antenna Port ............................................................................... 29
Protected Station ............................................................................... 30
Protected Ports ........................................................................... 30
Operation .................................................................................. 31
Configuration Management ............................................................. 31
Switch Over ............................................................................... 31
Switching Criteria ................................................................. 32
Hardware Manual Lock ........................................................... 33
Remote Control .................................................................... 33
Installation ................................................................................ 34
Mounting ............................................................................ 34
Cabling .............................................................................. 34
Power ............................................................................... 34
Maintenance .............................................................................. 35
Changing the Protected Station IP Addresses ................................. 35
Protected Station Software Upgrade ........................................... 35
Replacing a Protected Station Faulty Radio ................................... 36
Spares ...................................................................................... 37
Replacing a Faulty Protection Switch .......................................... 37
Data Driven Protected Station................................................................. 38
Operation .................................................................................. 38
Switch Over ........................................................................ 39
Configuration Management ...................................................... 39
Installation ................................................................................ 40
Mounting ............................................................................ 40
Cabling .............................................................................. 41
Power ............................................................................... 41
Duplexer Kits ..................................................................................... 42
UHF Duplexer Kits ................................................................. 42
VHF Duplexer Kits ................................................................. 42
USB RS-232 Serial Port .......................................................................... 43
USB RS-232 operation ............................................................. 43
Cabling Options .................................................................... 44
USB Retention Clip ................................................................ 44
5. Implementing the Network.......................................................... 45
Network Topologies ............................................................................. 45
Point-To-Point Network .......................................................... 45
Point-to-Multipoint Network ..................................................... 45
Point-to-Multipoint with Repeater 1 ............................................ 45
Point-to-Multipoint with Repeater 2 ............................................ 45
Initial Network Deployment ................................................................... 46
Install the Base Station .................................................................. 46
Installing the Remote Stations ......................................................... 46
Install a Repeater Station ............................................................... 46
Network Changes ................................................................................ 47
Adding a Repeater Station .............................................................. 47
Adding a Remote Station ................................................................ 47
Contents | 9
Aprisa SR User Manual
6. Preparation ............................................................................ 49
Bench Setup ...................................................................................... 49
Path Planning .................................................................................... 50
Antenna Selection and Siting ........................................................... 50
Base or Repeater Station ......................................................... 50
Remote station .................................................................... 51
Antenna Siting ..................................................................... 52
Coaxial Feeder Cables ................................................................... 53
Linking System Plan ...................................................................... 53
Site Requirements ............................................................................... 54
Power Supply .............................................................................. 54
Equipment Cooling ....................................................................... 54
Earthing and Lightning Protection ..................................................... 55
Feeder Earthing .................................................................... 55
Radio Earthing ..................................................................... 55
7. Installing the Radio ................................................................... 56
Mounting .......................................................................................... 56
Required Tools ............................................................................ 56
DIN Rail Mounting ........................................................................ 57
Rack Shelf Mounting ..................................................................... 58
Wall Mounting ............................................................................. 58
Installing the Antenna and Feeder Cable .................................................... 59
Connecting the Power Supply ................................................................. 60
External Power Supplies ................................................................. 60
Spare Fuses ................................................................................ 61
Additional Spare Fuses ............................................................ 62
10 | Contents
Aprisa SR User Manual
8. Managing the Radio ................................................................... 63
SuperVisor ........................................................................................ 63
Connecting to SuperVisor ............................................................... 63
Management PC Connection ..................................................... 64
PC Settings for SuperVisor ....................................................... 65
Login to SuperVisor................................................................ 69
Logout of SuperVisor .............................................................. 70
SuperVisor Page Layout ........................................................... 71
SuperVisor Menu .......................................................................... 75
SuperVisor Menu Access .......................................................... 76
SuperVisor Menu Items ........................................................... 77
Standard Radio............................................................................ 78
Terminal ............................................................................ 78
Radio ................................................................................ 90
Serial .............................................................................. 102
Ethernet .......................................................................... 107
Networking ....................................................................... 112
Security ........................................................................... 116
Maintenance ..................................................................... 131
Events ............................................................................. 144
Software .......................................................................... 152
Network Status .................................................................. 167
Protected Station ...................................................................... 174
Terminal .......................................................................... 175
Maintenance ..................................................................... 190
Events ............................................................................. 194
Software .......................................................................... 197
Command Line Interface ..................................................................... 213
Connecting to the Management Port ................................................ 213
CLI Commands .......................................................................... 216
Viewing the CLI Terminal Summary ........................................... 217
Changing the Radio IP Address with the CLI ................................. 217
In-Service Commissioning .................................................................... 218
Before You Start ............................................................................... 218
What You Will Need .................................................................... 218
Antenna Alignment ............................................................................ 219
Aligning the Antennas ................................................................. 219
9. Maintenance .......................................................................... 221
No User-Serviceable Components ........................................................... 221
Radio Software Upgrade ...................................................................... 222
Network Software Upgrade ........................................................... 222
Upgrade Process ................................................................. 222
Single Radio Software Upgrade ....................................................... 223
File Transfer Method ............................................................ 223
USB Boot Upgrade Method ..................................................... 224
Software Downgrade ............................................................ 225
Contents | 11
Aprisa SR User Manual
10. Interface Connections ............................................................... 226
RJ45 Connector Pin Assignments ............................................................ 226
Ethernet Interface Connections ............................................................. 226
RS-232 Serial Interface Connections ........................................................ 227
Hardware Alarms Connections ............................................................... 227
Protection Switch Remote Control Connections .......................................... 227
11. Alarm Types and Sources ........................................................... 228
Alarm Types .................................................................................... 228
Alarm Events ............................................................................ 228
Informational Events ................................................................... 231
12. Specifications ......................................................................... 232
RF Specifications .............................................................................. 232
Frequency Bands ....................................................................... 232
Channel Sizes ........................................................................... 232
Transmitter ............................................................................. 232
Receiver ................................................................................. 233
Modem ................................................................................... 233
Data Payload Security ................................................................. 233
Interface Specifications ...................................................................... 234
Ethernet Interface ..................................................................... 234
RS-232 Asynchronous Interface ....................................................... 235
Hardware Alarms Interface ........................................................... 235
Protection Switch Specifications ............................................................ 235
Power Specifications .......................................................................... 236
Power Supply ............................................................................ 236
Power Consumption .................................................................... 236
Power Dissipation ...................................................................... 237
General Specifications ........................................................................ 238
Environmental .......................................................................... 238
Mechanical .............................................................................. 238
Compliance .............................................................................. 238
13. Product End Of Life .................................................................. 239
End-of-Life Recycling Programme (WEEE) ................................................. 239
The WEEE Symbol Explained .......................................................... 239
WEEE Must Be Collected Separately ................................................. 239
YOUR ROLE in the Recovery of WEEE ................................................ 239
EEE Waste Impacts the Environment and Health .................................. 239
14. Abbreviations ......................................................................... 241
15. Index ................................................................................... 242
Getting Started | 13
Aprisa SR User Manual
Phase 1:
Pre-installation
1.
Confirm path planning.
Page 50
2.
Ensure that the site preparation is complete:
Power requirements
Tower requirements
Environmental considerations, for example, temperature control
Mounting space
Page 53
Phase 2:
Installing the radios
1.
Mount the radio.
Page 56
2.
Connect earthing to the radio.
Page 55
3.
Confirm that the:
Antenna is mounted and visually aligned
Feeder cable is connected to the antenna
Feeder connections are tightened to recommended level
Tower earthing is complete
4.
Install lightning protection.
Page 55
5.
Connect the coaxial jumper cable between the lightning protection and the
radio antenna port.
Page 59
6.
Connect the power to the radio.
Page 60
1. Getting Started
This section is an overview of the steps required to commission an Aprisa SR radio network in the field:
14 | Getting Started
Aprisa SR User Manual
Phase 3:
Establishing the link
1.
If radio’s IP address is not the default IP address (169.254.50.10 with a subnet
mask of 255.255.0.0) and you don’t know the radio’s IP address see ‘Command
Line Interface’ on page 213.
Page 213
2.
Connect the Ethernet cable between the radio’s Ethernet port and the PC.
3.
Confirm that the PC IP settings are correct for the Ethernet connection:
IP address
Subnet mask
Gateway IP address
Page 65
4.
Open a web browser and login to the radio.
Page 69
5.
Set or confirm the RF characteristics:
TX and RX frequencies
TX output power
Page 92
6.
Compare the actual RSSI to the expected RSSI value (from your path planning).
7.
Align the antennas.
Page 219
8.
Confirm that the radio is operating correctly; the OK, DATA, CPU and RF LEDs
are light green (the AUX LED will be off).
Introduction | 15
Aprisa SR User Manual
4RF Limited
26 Glover Street, Ngauranga
PO Box 13-506
Wellington 6032
New Zealand
E-mail
support@4rf.com
Web site
www.4rf.com
Telephone
+64 4 499 6000
Facsimile
+64 4 473 4447
Attention
Customer Services
2. Introduction
About This Manual
What It Covers
This user manual describes how to install and configure an Aprisa SR point-to-multipoint digital radio
network.
It specifically documents an Aprisa SR radio running system software version 1.6.2.
It is recommended that you read the relevant sections of this manual before installing or operating the
radios.
Who Should Read It
This manual has been written for professional field technicians and engineers who have an appropriate
level of education and experience.
Contact Us
If you experience any difficulty installing or using Aprisa SR after reading this manual, please contact
Customer Support or your local 4RF representative.
Our area representative contact details are available from our website:
What’s in the Box
Inside the box you will find:
One Aprisa SR radio fitted with a power connector.
One Aprisa SR Accessory kit containing the following:
Aprisa SR CD
Aprisa SR Quick Start Guide
Management Cable
16 | Introduction
Aprisa SR User Manual
Aprisa SR Quick Start Guide
Aprisa SR CD
Management Cable
USB Cable USB A to USB micro B, 1m
Aprisa SR Accessory Kit
The accessory kit contains the following items:
Aprisa SR CD Contents
The Aprisa SR CD contains the following:
Software
The latest version of the radio software (see ‘Radio Software Upgrade’ on page 222)
USB Serial Driver
Web browsers - Mozilla Firefox and Internet Explorer are included for your convenience
Adobe™ Acrobat® Reader® which you need to view the PDF files on the Aprisa SR CD
Documentation
User manual - an electronic (PDF) version for you to view online or print
Product collateral - application overviews, product description, quick start guide, case studies,
software release notes and white papers
About the Radio | 17
Aprisa SR User Manual
3. About the Radio
The 4RF Aprisa SR Radio
The 4RF Aprisa SR is a point-to-multipoint digital radio providing secure narrowband wireless data
connectivity for SCADA, infrastructure and telemetry applications.
The radios carry a combination of serial data and Ethernet data between the base station, repeater
stations and remote stations.
A single Aprisa SR is configurable as a point-to-multipoint base station, a remote station or a repeater
station.
18 | About the Radio
Aprisa SR User Manual
Configuration
Maximum Number Of Remotes
Non Protected Base Station
500
Protected Base Station
150
Product Overview
Network Coverage and Capacity
In a simple point-to-multipoint network, an Aprisa SR, configured as a base station, will communicate with
multiple remote units in a given coverage area. With a link range of up to 60 km, a typical deployment
will have 30 – 150 remote stations operating to the base station. However, geographic features, such as
hills, mountains, trees and foliage, or other path obstructions, such as buildings, tend to limit radio
coverage. Additionally, geography may reduce network capacity at the edge of the network where errors
may occur and require retransmission. However, the Aprisa SR uses Forward Error Correction (FEC) which
greatly improves the sensitivity performance of the radio resulting in less retries and minimal reduction in
capacity.
Ultimately, the overall performance of any specific network will be defined by a range of factors including
the geographic location, the number of remote stations in the base station coverage area and the traffic
profile across the network. Effective network design will distribute the total number of remote stations
across the available base stations to ensure optimal geographic coverage and network capacity.
The following are the maximum number of remotes that can operate to a base station for the product
configuration:
Remote Messaging
On start-up, the remote station transmits a registration message to the base stations which responds with
a registration response. This allows the base station to record the details of all the remote stations active
in the network.
If a remote station cannot register with the base station after multiple attempts (RF LED flashing red)
within 10 minutes, it will automatically reboot. If a remote station has registered with the base station
but then loses communication, it will automatically reboot within 6 minutes.
There are two message types in the Aprisa SR network, broadcast messages and unicast messages.
Broadcast messages are transmitted by the base station to the remote stations and unicast messages are
transmitted by the remote station to the base station.
All remotes within the coverage area will receive broadcast messages and pass them on to either the
Ethernet or serial interface. The RTU determines if the message is intended for it and will accept it or
discard it.
Only the base station can receive the unicast messages transmitted from the remote station. Unicast
messages are ignored by other remote stations which may be able to receive them.
About the Radio | 19
Aprisa SR User Manual
Repeater Messaging
The Aprisa SR uses a routed protocol throughout the network whereby messages contain source and
destination addresses. Upon registration, the radios populate an internal neighbor table to identify the
radios in the network. The remote stations will register with a base station, or a repeater, and the
repeater registers with a base station. In networks with a repeater, the repeater must register with the
base station before the remotes can register with the repeater.
Additionally, all messages contain a ‘message type’ field in the header and messages are designated as
either a ‘broadcast’ message, originating from a base station, or a ‘unicast’ message, originating from a
remote station.
In a network with a repeater, or multiple repeaters, the base station broadcasts a message which contains
a message type, a source address and a destination address. The repeater receives the message and
recognizes it is a broadcast message, from the message type and source address and re-broadcasts the
message across the network. All remote stations in the coverage area will receive the message but only
the radio with the destination address will act upon the message.
Similarly, the remote station will send a unicast message which contains a message type (unicast) a source
address and a destination address (the base station). The repeater will receive this message; recognize
the message type and source address and forward it to the destination address.
It is this methodology which prevents repeater-repeater loops. If there is repeater (A) which, in some
circumstances, is able to pick up the RF signal from another repeater (B), it will not forward the message
as it will only forward broadcast messages from the base station (recognized by the source address). Fo r
unicast messages the repeater (A) will recognize that the message (from repeater (B)) is not from a
remote with which it has an association and similarly ignore the message.
20 | About the Radio
Aprisa SR User Manual
Product Features
Functions
Point-to-Point (PTP) or Point-to-Multipoint (PMP) operation half duplex
Licensed frequency bands:
VHF 136-174 MHz
UHF 400-470 MHz
Channel sizes:
12.5 kHz
25 kHz
Typical deployment of 30 remote stations from one base station with a practical limit of a few
hundred remote stations
Transparent to all common SCADA protocols; e.g. Modbus, IEC 60870-5-101/104, DNP3 or similar
Dual antenna port option for external duplexers or filters (half duplex operation)
Two Ethernet data interfaces plus two RS-232 asynchronous data interfaces
Terminal server operation for transporting RS-232 traffic over IP
Data encryption and authentication
Layer 2 Ethernet and layer 3 IP filtering
SNMPv2 and SNMPv3 support
Radio and user interface redundancy (provided with Aprisa SR Protected Station)
Complies with international standards, including ETSI RF, EMC, safety and environmental standards
Performance
Long distance operation
High transmit power
Low noise receiver
Forward Error Correction
Electronic tuning over the frequency band
Thermal management for high power over a wide temperature range
Usability
Configuration / diagnostics via front panel Management Port USB interface, Ethernet interface
Built-in webserver with full configuration, diagnostics and monitoring functionality, including
remote station configuration / diagnostics over the radio link
LED display for on-site diagnostics
Software upgrade and diagnostic reporting via the Host Port USB flash drive
Over-the-air software distribution and upgrades
Simple installation with integrated mounting holes for wall, DIN rail and rack shelf mounting
About the Radio | 21
Aprisa SR User Manual
Option
Function
Access Request
Channel access scheme where the base stations controls the
communication on the channel. Remotes ask for access to the
channel, and the base station grants access if the channel is not
occupied.
Listen Before Send
Channel access scheme where network elements listen to ensure
the channel is clear, before trying to access the channel.
Architecture
Product Operation
There are three components to the wireless interface: the Physical Layer (PHY), the Data Link Layer (DLL)
and the Network Layer. These three layers are required to transport data across the wireless channel in
the Point-to-Multipoint (PMP) configuration. The Aprisa SR DLL is largely based on the 802.15.4 MAC layer
using a proprietary implementation.
Physical Layer
The Aprisa SR PHY uses a one or two frequency ½ duplex transmission mode which eliminates the need for
a duplexer. However, a Dual Antenna port option is available for separate transmit and receive antenna
connection to support external duplexers or filters (half duplex operation).
Remote nodes are predominantly in receive mode with only sporadic bursts of transmit data. This reduces
power consumption.
The Aprisa SR is a packet based radio. Data is sent over the wireless channel in discrete packets / frames,
separated in time. The PHY demodulates data within these packets with coherent detection.
The Aprisa SR PHY provides carrier, symbol and frame synchronization predominantly through the use of
preambles. This preamble prefixes all packets sent over the wireless channel which enables fast
Synchronization.
Data Link Layer / MAC layer
The Aprisa SR PHY enables multiple users to be able to share a single wireless channel; however a DLL is
required to manage data transport. The two key components to the DLL are channel access and hop by
hop transmission.
Channel Access
The Aprisa SR radio has two modes of channel access, Access Request and Listen Before Send.
22 | About the Radio
Aprisa SR User Manual
Access Request
This scheme is particularly suited to digital SCADA systems where all data flows through the base station.
In this case it is important that the base station has contention-free access as it is involved in every
transaction. The channel access scheme assigns the base station as the channel access arbitrator and
therefore inherently it has contention-free access to the channel. This means that there is no possibility
of contention on data originating from the base station. As all data flows to or from the base station, this
significantly improves the robustness of the system.
All data messages are controlled via the AG (access grant) control message and therefore there is no
possibility of contention on the actual end user data. If a remote station accesses the channel, the only
contention risk is on the AR (access request) control message. These control messages are designed to be
as short as possible and therefore the risk of collision of these control messages is significantly reduced.
Should collisions occur these are resolved using a random back off and retry mechanism.
As the base station controls all data transactions multiple applications can be effectively handled,
including a mixture of polling and report by exception.
Listen Before Send
The Listen Before Send channel access scheme is realized using Carrier Sense Multiple Access (CSMA). In
this mode, a pending transmission requires the channel to be clear. This is determined by monitoring the
channel for other signals for a set time prior to transmission. This results in reduced collisions and
improved channel capacity.
There are still possibilities for collisions with this technique e.g. if two radios simultaneously determine
the channel is clear and transmit at the same time. In this case an acknowledged transaction may be used.
The transmitter requests an ACK to ensure that the transmission has been successful. If the transmitter
does not receive an ACK, then random backoffs are used to reschedule the next transmission.
Hop by Hop Transmission
Hop by Hop Transmission is realized in the Aprisa SR by adding a MAC address header to the packet. For
802.15.4, there are 2 addresses, the source and destination addresses.
About the Radio | 23
Aprisa SR User Manual
Network Layer
Packet Routing
Packet routing is realized in the Aprisa SR by adding a network address header to the packet. This contains
source and destination addresses. For the Network Layer, there are 2 addresses, the address of the
originating radio and the address of the terminating radio (i.e. end to end network). This is required for
routing packets across multiple hops e.g. PMP with repeaters.
The Aprisa SR uses an automated method for performing address assignment and routing information.
There are two types of packets: unicast and broadcast. Only the base station sends broadcasts which are
received by all remote stations. User packets are not interpreted as the radio link is transparent.
Traffic
Data originating on the base station is broadcast to all repeater stations and remote stations
Data originating on a remote station is unicast to the base station only
This can be via multiple repeater stations.
Data originating on a repeater station is unicast to the base station only
Data originating on a base station serial port is terminated on remote station serial ports only
Data originating on a base station Ethernet port is terminated on remote station Ethernet ports or
serial ports (Terminal Server mode)
User Traffic
User traffic is prioritized depending on the Serial and Ethernet Data Priority options (see Traffic Settings
on ‘Radio > Channel Setup’ on page 97).
If the Serial and Ethernet Data Priority options are equal, then first come first served is invoked.
Repeater stations repeat traffic also on a first come first served basis.
Management Traffic
Management Traffic is prioritized relative to user traffic priority (see Traffic Settings on ‘Radio > Channel
Setup’ on page 97).
24 | About the Radio
Aprisa SR User Manual
Security
The Aprisa SR provides security features to implement the key recommendations for industrial control
systems. The security provided builds upon the best in class from multiple standards bodies, including:
IEC/TR 62443 (TC65) ‘Industrial Communications Networks – Network and System Security’
IEC/TS 62351 (TC57) ‘Power System Control and Associated Communications – Data and
Communication Security’
The security features implemented are:
Data encryption
Counter Mode Encryption (CTR) using Advanced Encryption Standard (AES)
Data authentication
Cipher Block Chaining Message Authentication Code (CBC-MAC) using Advanced Encryption
Standard (AES)
Data payload security
CCM Counter with CBC-MAC integrity (NIST special publication 800-38C)
Secured management interface protects configuration
Address filtering enables traffic source authorization
Proprietary physical layer protocol and modified MAC layer protocol based on standardized IEEE
802.15.4
Licensed radio spectrum protects against interference
About the Radio | 25
Aprisa SR User Manual
Interfaces
Antenna Interface
Single Antenna Option
1 x TNC, 50 ohm, female connector
Dual Antenna Port Option
2 x TNC, 50 ohm, female connectors
Ethernet Interface
2 x ports 10/100 base-T Ethernet layer 2 switch using RJ45
Used for Ethernet user traffic and product management.
RS-232 Interface
1x RS-232 asynchronous port using RJ45 connector
1x RS-232 asynchronous port using USB host port with USB to RS-232 converter
Used for RS-232 asynchronous user traffic only.
USB Interfaces
1 x Management Port using USB micro type B connector
Used for product configuration with the Command Line Interface (CLI).
1 x Host Port using USB standard type A connector
Used for software upgrade and diagnostic reporting.
Alarms
2 x hardware alarm inputs on the power and alarm connector
The alarm states can be transported over the radio link and used to generate SNMP traps.
26 | About the Radio
Aprisa SR User Manual
Designator
Description
A1 / A2
The A1, A2 are alarm connections are used in the Protected
Station.
10 - 30 VDC; 3A
+10 to +30 VDC (negative ground) DC power input using
Phoenix Contact 4 pin male screw fitting connector.
AC/DC and DC/DC power supplies are available as accessories.
See ‘External Power Supplies’ on page 60.
ETHERNET 1
Integrated 10Base-T/100Base-TX layer-2 Ethernet switch using
RJ45 connector.
Used for Ethernet user traffic and product management.
See ‘Ethernet > Port Setup’ on page 108.
ETHERNET 2
Integrated 10Base-T/100Base-TX layer-2 Ethernet switch using
RJ45 connector.
Used for Ethernet user traffic and product management.
See ‘Ethernet > Port Setup’ on page 108.
MGMT
Management Port using USB micro type B connector.
Used for product configuration with the Command Line
Interface.
See ‘Connecting to the Management Port’ on page 213.
Host Port using USB standard type A connector.
Used for software upgrade and diagnostic reporting.
See ‘Radio Software Upgrade’ on page 222 and ‘Maintenance >
General’ on page 134.
SERIAL
RS-232 traffic interface using a RJ45 connector.
Used for RS-232 asynchronous user traffic only.
See ‘Serial’ on page 102.
ANT
(Antenna connector)
TNC, 50 ohm, female connector for connection of antenna
feeder cable.
See ‘Coaxial Feeder Cables’ on page 53.
Front Panel Connections
All connections to the radio are made on the front panel. The functions of the connectors are (from left to
right):
About the Radio | 27
Aprisa SR User Manual
OK
DATA
CPU
RF
AUX
Solid
Red
Alarm present
with severity
Critical, Major
and Minor
RF path fail
Flashing
Red
Radio not
connected to a
base station
Solid
Orange
Alarm present
with Warning
Severity
Standby radio
in Protected
Station
Flashing
Orange
Tx Data or Rx
Data on the
USB
management
or data port
Device detect
on the USB
host port
RF path TX is
active
Diagnostics
Function
Active
Flashing
Green
Tx Data or Rx
Data on the
serial port
RF path RX is
active
Solid
Green
Power on and
functions OK
and no alarms
All interface
ports are OK
Processor Block
is OK and
Active radio in
Protected
Station
RF path is OK
LED Colour
Severity
Green
No alarm – information only
Orange
Warning alarm
Red
Critical, major or minor alarm
LED Display Panel
The Aprisa SR has an LED Display panel which provides on-site alarms / diagnostics without the need for
PC.
Normal Operation
In normal radio operation, the LEDs indicate the following conditions:
Single Radio Software Upgrade
During a radio software upgrade, the LEDs indicate the following conditions:
Software upgrade started - the OK LED flashes orange
Software upgrade progress indicated by running AUX to DATA LEDs
Software upgrade completed successfully - the OK LED solid orange
Software upgrade failed - any LED flashing red during the upgrade
28 | About the Radio
Aprisa SR User Manual
Network Software Upgrade
During a network software upgrade, the AUX LED flashes orange on the base station and all remote
stations.
Test Mode
Remote station and repeater station radios have a Test Mode which presents a real time visual display of
the RSSI on the LED Display panel. This can be used to adjust the antenna for optimum signal strength (see
‘Maintenance > Test Mode’ on page 137 for Test Mode options).
To enter Test Mode, press and hold the ENTER button on the radio LED panel until all the LEDs flash green
(about 3 - 5 seconds). The response time is variable and can be up to 5 seconds.
To exit Test Mode, press and hold the ENTER button until all the LEDs flash red (about 3 – 5 seconds).
The RF LED will be green if the network is operating correctly.
Note: Test Mode traffic has a low priority but could affect customer traffic depending on the relative
priorities setup.
The RSSI result is displayed on the LED Display panel as a combination of LED states:
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