4RF Aprisa SR+ User manual

November 2015
Version 1.5.3

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Aprisa SR+ User Manual 1.5.3
Copyright
Copyright © 2015 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 ([e-mail]).

2|
Aprisa SR+ User Manual 1.5.3
Compliance General
The Aprisa SR+ 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:
12.5 kHz and 25 kHz
Channel
50 kHz Channel
Radio performance
EN 300 113-2
EN 302 561 (pending)
EMC
EN 301 489 Parts 1 & 4
Environmental
EN 300 019, Class 3.4
Ingress Protection IP51
Safety
EN 60950-1:2006
Class 1 division 2 for hazardous locations
Frequency band
Channel size
Power input
Notified
body
135-175 MHz
12.5 kHz, 25 kHz
12 VDC
320-400 MHz
12.5 kHz, 25 kHz, 50 kHz
12 VDC
400-470 MHz
12.5 kHz, 25 kHz, 50 kHz
12 VDC
450-520 MHz
12.5 kHz, 25 kHz
12 VDC

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Aprisa SR+ User Manual 1.5.3
Compliance Federal Communications Commission
The Aprisa SR+ radio is designed to comply with the Federal Communications Commission (FCC)
specifications as follows:
Radio
47CFR part 24, part 90 and part 101 Private Land Mobile
Radio Services
EMC
47CFR part 15 Radio Frequency Devices, EN 301 489 Parts
1 & 4
Environmental
EN 300 019, Class 3.4
Ingress Protection IP51
Safety
EN 60950-1:2006
Class 1 division 2 for hazardous locations
Frequency Band *
Channel size
Power
input
Authorization
FCC ID
135-175 MHz
12.5 kHz, 25 kHz
12 VDC
Part 90
Pending
215-240 MHz
12.5 kHz, 25 kHz,
50 kHz
12 VDC
Part 90
UIPSQ215M141
400-470 MHz
12.5 kHz, 25 kHz,
50 kHz
12 VDC
Part 90
UIPSQ400M131
450-520 MHz
12.5 kHz, 25 kHz
12 VDC
Part 90
UIPSQ450M140
896-902 MHz
12.5 kHz, 25 kHz,
50 kHz
12 VDC
Part 24 /
Part 90
UIPSQ896M141
928-960 MHz
12.5 kHz, 25 kHz,
50 kHz
12 VDC
Part 24 /
Part 90
UIPSQ928M141
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.
* The Frequency Band is not an indication of the exact frequencies approved by FCC.

4|
Aprisa SR+ User Manual 1.5.3
Compliance Industry Canada
The Aprisa SR+ radio is designed to comply with Industry Canada (IC) specifications as follows:
Radio
RSS-119 / RSS-134
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.
Environmental
EN 300 019, Class 3.4
Ingress Protection IP51
Safety
EN 60950-1:2006
Class 1 division 2 for hazardous locations
Frequency Band *
Channel size
Power
input
Authorization
IC
135-175 MHz
12.5 kHz, 25 kHz
12 VDC
RSS-119
Pending
215-240 MHz
12.5 kHz
12 VDC
RSS-119
6772A-SQ215M141
400-470 MHz
12.5 kHz, 25 kHz,
50 kHz
12 VDC
RSS-119
6772A-SQ400M131
896-902 MHz
12.5 kHz, 25 kHz,
50 kHz
12 VDC
RSS-119 and
RSS-134
6772A-SQ896M141
928-960 MHz
12.5 kHz, 25 kHz,
50 kHz
12 VDC
RSS-119 and
RSS-134
6772A-SQ928M141
* The Frequency Band is not an indication of the exact frequencies approved by IC.
Compliance Brazil
Este produto será comercializado no Brasil com as configurações abaixo:
Faixa de frequência: 406,10 a 413,05, 423,05 a 430 MHz, 451,00625 a 452,0065 MHz, 459 a 460 MHz,
461,0025 a 462,00625 MHz e 469 a 470 MHz.
Modulações: QPSK, 16QAM e 64QAM
BW: 12,5 e 25 KHz.

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Aprisa SR+ User Manual 1.5.3
Compliance Hazardous Locations Notice
This product is suitable for use in Class 1, Division 2, Groups A - D hazardous locations or non-hazardous
locations.
The following text is printed on the Aprisa SR+ fascia:
WARNING: EXPLOSION HAZARD - Do not connect or disconnect while circuits are live unless area is known
to be non-hazardous.
The following text is printed on the Aprisa SR+ where the end user is in Canada:
AVERTISSEMENT: RISQUE D'EXPLOSION - Ne pas brancher ou débrancher tant que le circuit est sous
tension, àmoins qu'il ne s'agisse d'un emplacement non dangereux.
The USB service ports are not to be used unless the area is known to be non-hazardous.

6|
Aprisa SR+ User Manual 1.5.3
RF Exposure Warning
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) Note 1
Maximum Antenna
Gain (dBi)
Minimum Separation
Distance
(m)
135
+ 37
15
3.5
175
+ 37
15
3.5
215
+ 37
15
3.5
240
+ 37
15
3.5
320
+ 37
15
3.5
400
+ 37
15
3.0
450
+ 37
15
3.0
470
+ 37
15
3.0
520
+ 37
15
3.0
896
+ 37
28
10.0
902
+ 37
28
10.0
928
+ 37
28
9.5
960
+ 37
28
9.5
Note 1: The Peak Envelope Power (PEP) at maximum set power level is +41 dBm.

Contents | 7
Aprisa SR+ User Manual 1.5.3
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
Automatic Registration ..................................................................18
Remote Messaging........................................................................18
Store and Forward Repeater............................................................19
Repeater Packet Forwarding.....................................................19
Repeater Messaging ...............................................................22
Peer To Peer Communication Between Remote Radios......................23
Product Features ................................................................................24
Functions ..................................................................................24
Security ....................................................................................25
Performance ..............................................................................26
Usability ...................................................................................26
System Gain vs FEC Coding .............................................................27
Architecture......................................................................................28
Product Operation........................................................................28
Physical Layer.............................................................................28
Data Link Layer / MAC layer ............................................................29
Channel Access ....................................................................29
Hop by Hop Transmission.........................................................30
Adaptive Coding Modulation .....................................................30
Network Layer ............................................................................31
Packet Routing.....................................................................31
Static IP Router....................................................................32
Bridge Mode with VLAN Aware ..................................................35
VLAN Bridge Mode Description ..................................................36
Avoiding Narrow Band Radio Traffic Overloading....................................38
Interfaces.........................................................................................40
Antenna Interface ........................................................................40
Ethernet Interface .......................................................................40
RS-232 / RS-485 Interface...............................................................40
USB Interfaces ............................................................................40
Protect Interface .........................................................................40
Alarms Interface..........................................................................40

8| Contents
Aprisa SR+ User Manual 1.5.3
Front Panel Connections .......................................................................41
LED Display Panel ...............................................................................42
Normal Operation ........................................................................42
Single Radio Software Upgrade.........................................................43
Network Software Upgrade .............................................................43
Test Mode .................................................................................44
Network Management ..........................................................................45
Hardware Alarm Inputs / Outputs ............................................................46
Alarm Input to SNMP Trap...............................................................46
Alarm Input to Alarm Output ...........................................................46
Aprisa SR Alarm Input to Aprisa SR+ Alarm Output ..................................46
4. Implementing the Network.......................................................... 47
Network Topologies .............................................................................47
Point-To-Point Network ..........................................................47
Point-to-Multipoint Network.....................................................47
Point-to-Multipoint with Repeater 1............................................47
Point-to-Multipoint with Repeater 2............................................47
Initial Network Deployment ...................................................................48
Install the Base Station ..................................................................48
Installing the Remote Stations .........................................................48
Install a Repeater Station ...............................................................48
Network Changes................................................................................49
Adding a Repeater Station ..............................................................49
Adding a Remote Station ................................................................49
5. Preparation ............................................................................ 51
Bench Setup......................................................................................51
Path Planning ....................................................................................52
Antenna Selection and Siting ...........................................................52
Base or Repeater Station.........................................................52
Remote station ....................................................................53
Antenna Siting .....................................................................54
Coaxial Feeder Cables ...................................................................55
Linking System Plan ......................................................................55
Site Requirements...............................................................................56
Power Supply..............................................................................56
Equipment Cooling .......................................................................56
Earthing and Lightning Protection .....................................................57
Feeder Earthing....................................................................57
Radio Earthing .....................................................................57
6. Installing the Radio ................................................................... 58
Mounting..........................................................................................58
Required Tools............................................................................58
DIN Rail Mounting ........................................................................59
Rack Shelf Mounting .....................................................................60
Wall Mounting.............................................................................61
Installing the Antenna and Feeder Cable ....................................................62
Connecting the Power Supply .................................................................63
External Power Supplies.................................................................63
Spare Fuses................................................................................64
Additional Spare Fuses............................................................65

Contents | 9
Aprisa SR+ User Manual 1.5.3
7. Managing the Radio ................................................................... 67
SuperVisor ........................................................................................67
PC Requirements for SuperVisor .......................................................68
Connecting to SuperVisor ...............................................................69
Management PC Connection .....................................................70
PC Settings for SuperVisor .......................................................71
Login to SuperVisor................................................................75
Logout of SuperVisor..............................................................76
SuperVisor Page Layout...........................................................77
SuperVisor Menu ...................................................................79
SuperVisor Menu Access ..........................................................80
SuperVisor Menu Items ...........................................................82
Standard Radio............................................................................83
Terminal ............................................................................83
Radio ................................................................................97
Serial .............................................................................. 118
Ethernet .......................................................................... 129
IP................................................................................... 139
QoS ................................................................................ 148
Security ........................................................................... 170
Maintenance ..................................................................... 192
Events ............................................................................. 210
Software .......................................................................... 223
Monitoring ........................................................................ 241
Network Status .................................................................. 259
Protected Station ...................................................................... 266
Terminal .......................................................................... 267
Radio .............................................................................. 275
Ethernet .......................................................................... 277
IP................................................................................... 278
Security ........................................................................... 282
Maintenance ..................................................................... 284
Events ............................................................................. 295
Software .......................................................................... 298
Command Line Interface ..................................................................... 317
Connecting to the Management Port ................................................ 317
CLI Commands .......................................................................... 320
Viewing the CLI Terminal Summary........................................... 321
Changing the Radio IP Address with the CLI ................................. 321
8. In-Service Commissioning ..........................................................322
Before You Start............................................................................... 322
What You Will Need.................................................................... 322
Antenna Alignment............................................................................ 323
Aligning the Antennas ................................................................. 323

10 | Contents
Aprisa SR+ User Manual 1.5.3
9. Product Options ......................................................................324
Data Interface Ports .......................................................................... 324
Full Duplex Base Station ..................................................................... 324
Protected Station ............................................................................. 325
Protected Ports......................................................................... 326
Operation................................................................................ 326
Switch Over ...................................................................... 326
Switching Criteria ............................................................... 327
Monitored Alarms................................................................ 328
Configuration Management .................................................... 329
Hardware Manual Lock ......................................................... 330
Remote Control.................................................................. 330
L2 / L3 Protection Operation .................................................. 331
Hot-Swappable................................................................... 331
Antenna and Duplexer Options ................................................ 332
Installation .............................................................................. 334
Mounting.......................................................................... 334
Cabling............................................................................ 335
Power ............................................................................. 337
Alarms............................................................................. 337
Maintenance ............................................................................ 338
Changing the Protected Station IP Addresses ............................... 338
Creating a Protected Station .................................................. 339
Replacing a Protected Station Faulty Radio ................................. 339
Replacing a Faulty Power Supply.............................................. 340
Replacing a Faulty Protection Switch ........................................ 340
Spares .................................................................................... 340
Data Driven Protected Station............................................................... 341
Operation................................................................................ 341
Over The Air Compatibility .................................................... 341
Switch Over ...................................................................... 342
Configuration Management .................................................... 342
Power ............................................................................. 342
Installation .............................................................................. 343
Mounting.......................................................................... 343
Cabling............................................................................ 343
Duplexer Kits................................................................................... 344
Radio Duplexer Kits .................................................................... 344
Protected Station Duplexer Kits...................................................... 346
USB RS-232 / RS-485 Serial Port............................................................. 348
USB RS-232 / RS-485 operation....................................................... 348
USB RS-232 Cabling Options........................................................... 349
USB RS-485 Cabling Options........................................................... 349
USB Retention Clip .............................................................. 350
Migration Master Station ..................................................................... 351
Operation................................................................................ 351
RF Switch ......................................................................... 352
Redundancy ...................................................................... 352
Operating Configurations....................................................... 352
Configuration Management .................................................... 352
Power ............................................................................. 353
Migration Plan .......................................................................... 354
Installation .............................................................................. 356
Mounting.......................................................................... 356
Cabling............................................................................ 357
Accessories ....................................................................... 358

Contents | 11
Aprisa SR+ User Manual 1.5.3
10. Maintenance ..........................................................................359
No User-Serviceable Components........................................................... 359
Software Upgrade ............................................................................. 360
Network Software Upgrade ........................................................... 360
Non-Protected Network Upgrade Process.................................... 360
Protected Network Upgrade Process ......................................... 362
Single Radio Software Upgrade....................................................... 364
File Transfer Method............................................................ 364
USB Boot Upgrade Method ..................................................... 365
Software Downgrade ............................................................ 365
Protected Station Software Upgrade ................................................ 366
11. Interface Connections...............................................................367
RJ45 Connector Pin Assignments............................................................ 367
Ethernet Interface Connections ............................................................. 367
RS-232 Serial Interface Connections........................................................ 368
RS-232 Pinout .................................................................... 368
RS-232 Customer Cable Wiring ................................................ 368
RS-232 RJ45 LED Indicators .................................................... 368
Alarm Interface Connections ................................................................ 369
Protection Switch Remote Control Connections .......................................... 369
12. Alarm Types and Sources...........................................................370
Alarm Types.................................................................................... 370
Alarm Events ............................................................................ 371
Informational Events................................................................... 376
13. Specifications .........................................................................377
RF Specifications .............................................................................. 377
Frequency Bands ....................................................................... 377
Channel Sizes ........................................................................... 378
Receiver ................................................................................. 385
Transmitter ............................................................................. 388
Modem ................................................................................... 389
Data Payload Security ................................................................. 389
Interface Specifications ...................................................................... 390
Ethernet Interface ..................................................................... 390
RS-232 Asynchronous Interface....................................................... 391
Hardware Alarms Interface ........................................................... 392
Protection Switch Specifications..................................................... 392
Power Specifications.......................................................................... 393
Power Supply............................................................................ 393
Power Consumption .................................................................... 394
Power Dissipation ...................................................................... 394
General Specifications........................................................................ 395
Environmental .......................................................................... 395
Mechanical .............................................................................. 395
Compliance.............................................................................. 396

12 | Contents
Aprisa SR+ User Manual 1.5.3
14. Product End Of Life..................................................................397
End-of-Life Recycling Programme (WEEE) ................................................. 397
The WEEE Symbol Explained.......................................................... 397
WEEE Must Be Collected Separately ................................................. 397
YOUR ROLE in the Recovery of WEEE................................................ 397
EEE Waste Impacts the Environment and Health .................................. 397
15. Copyrights .............................................................................398
16. Abbreviations .........................................................................399
17. Index ...................................................................................400

Getting Started | 13
Aprisa SR+ User Manual 1.5.3
1. Getting Started
This section is an overview of the steps required to commission an Aprisa SR+ radio network in the field:
Phase 1:
Pre-installation
1.
Confirm path planning.
Page 52
2.
Ensure that the site preparation is complete:
Power requirements
Tower requirements
Environmental considerations, for example, temperature control
Mounting space
Page 55
Phase 2:
Installing the radios
1.
Mount the radio.
Page 58
2.
Connect earthing to the radio.
Page 57
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 57
5.
Connect the coaxial jumper cable between the lightning protection and the
radio antenna port.
Page 62
6.
Connect the power to the radio.
Page 63

14 | Getting Started
Aprisa SR+ User Manual 1.5.3
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 317.
Page 317
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 71
4.
Open a web browser and login to the radio.
Page 75
5.
Set or confirm the RF characteristics:
TX and RX frequencies
TX output power
Page 99
6.
Compare the actual RSSI to the expected RSSI value (from your path planning).
Page 44
7.
Align the antennas.
Page 323
8.
Confirm that the radio is operating correctly; the OK, MODE and AUX LEDs are
green.

Introduction | 15
Aprisa SR+ User Manual 1.5.3
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 1.5.3 .
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 training 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:
4RF Limited
26 Glover Street, Ngauranga
PO Box 13-506
Wellington 6032
New Zealand
E-mail
[email protected]
Web site
www.4rf.com
Telephone
[phone]
Facsimile
[phone]
Attention
Customer Services
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 1.5.3
Aprisa SR+ Accessory Kit
The accessory kit contains the following items:
Aprisa SR+ Quick Start Guide
Aprisa SR+ CD
Management Cable
USB Cable USB A to USB micro B, 1m
Aprisa SR+ CD Contents
The Aprisa SR+ CD contains the following:
Software
The latest version of the radio software (see ‘Software Upgrade’on page 360)
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 1.5.3
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 1.5.3
Product Overview
Network Coverage and Capacity
The Aprisa SR+ has a typical link range of up to 120 km, however, geographic features, such as hills,
mountains, trees and foliage, or other path obstructions, such as buildings, will 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 10W output power and Forward Error Correction
(FEC) which greatly improves the sensitivity and system gain 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 RF output power, the modulation used and its related receiver sensitivity, 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.
One base station can register and operate with up to 500 remote / repeater stations.
The practical limit of remote / repeater stations that can operate with one base station is determined by
a range of factors including the number of services, the packet sizes, the protocols used, the message
types and network timeouts.
Automatic Registration
On start-up, the remote station transmits a registration message to the base station 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 within 10 minutes, it will
automatically reboot. If remote is not able to register with base station in 5 attempts, then a ‘Network
Configuration Warning’ alarm event will be raised indicating that a remote is not registered with the base
station.
If a remote station has registered with the base station but then loses communication, it will
automatically reboot within 2 minutes.
Remote Messaging
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. These messages are commonly referred to as uplink
(unicast remote to base) and downlink (broadcast base to remote).
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.