4RF Aprisa SR+ Users Manual

April 2015

Version 1.3.0b

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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]).

Aprisa SR+ Product Description 1.3.0

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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		50 kHz Channel
		Channel
Radio performance		EN 300 113-2		EN 302 561 (pending)
EMC		EN 301 489 Parts 1 & 5
Environmental		EN 300 019, Class 3.4
		Ingress Protection code IP51
Safety		EN 60950-1:2006
		Class 1 div 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		12 VDC
450-520 MHz	12.5 kHz, 25 kHz		12 VDC

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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 code IP51
Safety		EN 60950-1:2006
		Class 1 div 2 for hazardous locations
Frequency Band *	Channel size			Power	Authorization	FCC ID
				input
135-175 MHz	12.5 kHz, 25 kHz			12 VDC	Part 90	Pending
215-240 MHz	12.5 kHz, 25 kHz,			12 VDC	Part 90	UIPSQ215M141
	50 kHz
400-470 MHz	12.5 kHz, 25 kHz			12 VDC	Part 90	Pending
450-520 MHz	12.5 kHz, 25 kHz			12 VDC	Part 90	UIPSQ450M140
896-902 MHz	12.5 kHz, 25 kHz,			12 VDC	Part 24 /	UIPSQ896M141
	50 kHz				Part 90
928-960 MHz	12.5 kHz, 25 kHz,			12 VDC	Part 24 /	UIPSQ928M140
	50 kHz				Part 90

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.

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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 code IP51
Safety		EN 60950-1:2006
		Class 1 div 2 for hazardous locations
Frequency Band *	Channel size		Power	Authorization	IC
			input
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		12 VDC	RSS-119	Pending
896-902 MHz	12.5 kHz, 25 kHz,		12 VDC	RSS-119 and	6772A-SQ896M141
	50 kHz			RSS-134
928-960 MHz	12.5 kHz, 25 kHz,		12 VDC	RSS-119 and	6772A-SQ928M140
	50 kHz			RSS-134

* 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: 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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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, à moins qu'il ne s'agisse d'un emplacement non dangereux.

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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	Maximum Antenna	Minimum Separation
	(dBm) Note 1	Gain (dBi)	Distance
			(m)
135	+ 37	15	2.5
175	+ 37	15	2.5
215	+ 37	15	2.5
216.5	+ 37	15	2.5
217.5	+ 33	15	2.5
215	+ 37	15	2.5
240	+ 37	15	2.5
320	+ 37	15	2.5
400	+ 37	15	3.0
450	+ 37	15	3.0
470	+ 37	15	3.0
520	+ 37	15	3.0
896	+ 37	28	7.5
902	+ 37	28	7.5
928	+ 37	28	7.5
960	+ 37	28	7.5

Note 1: The Peak Envelope Power (PEP) at maximum set power level is +41 dBm.

Aprisa SR+ Product Description 1.3.0

		Contents | 7
Contents
1.	Introduction............................................................................	11
	The 4RF Aprisa SR+ Radio ......................................................................	11
	Product Overview ...............................................................................	12
	Network Coverage and Capacity .......................................................	12
	Automatic Registration ..................................................................	12
	Remote Messaging........................................................................	12
	Store and Forward Repeater............................................................	13
	Repeater Packet Forwarding.....................................................	13
	Repeater Messaging ...............................................................	16
	Product Features ................................................................................	17
	Functions ..................................................................................	17
	Security ....................................................................................	18
	Performance ..............................................................................	19
	Usability ...................................................................................	19
	System Gain vs FEC Coding .............................................................	20
	Architecture......................................................................................	21
	Interfaces.........................................................................................	22
	Antenna Interface ........................................................................	22
	Ethernet Interface .......................................................................	22
	RS-232 / RS-485 Interface...............................................................	22
	USB Interfaces ............................................................................	22
	Protect Interface .........................................................................	22
	Alarms Interface..........................................................................	22
	Mounting..........................................................................................	23
	DIN Rail Mounting ........................................................................	23
	Rack Shelf Mounting .....................................................................	25
	Wall Mounting.............................................................................	26
2.	Product Options .......................................................................	27
	Interface Ports...................................................................................	27
	Full Duplex Base Station .......................................................................	27
	Protected Station ...............................................................................	28
	Protected Ports ...........................................................................	28
	Operation..................................................................................	29
	Switch Over ........................................................................	29
	Configuration Management ......................................................	29
	Power ...............................................................................	29
	Duplexer Kits.....................................................................................	30
	Radio Duplexer Kits ......................................................................	30
	Protected Station Duplexer Kits........................................................	31
	USB RS-232 / RS-485 Serial Port...............................................................	32
	USB RS-232 / RS-485 operation.........................................................	32

Aprisa SR+ Product Description 1.3.0

8 | Contents

3. Specifications ..........................................................................	33
RF Specifications ................................................................................	33
Frequency Bands .........................................................................	33
Channel Sizes .............................................................................	34
Receiver ...................................................................................	39
Transmitter ...............................................................................	42
Modem .....................................................................................	42
Data Payload Security ...................................................................	42
Interface Specifications ........................................................................	43
Ethernet Interface .......................................................................	43
RS-232 Asynchronous Interface.........................................................	44
Hardware Alarms Interface .............................................................	45
Protection Switch Specifications .......................................................	45
Power Specifications............................................................................	46
Power Supply..............................................................................	46
Power Consumption ......................................................................	47
Power Dissipation ........................................................................	47
General Specifications..........................................................................	48
Environmental ............................................................................	48
Mechanical ................................................................................	48
Compliance................................................................................	49

4. Management ...........................................................................	51
SuperVisor ........................................................................................	51
Viewing the Aprisa SR+ Terminal Settings ............................................	52
Configuring the Aprisa SR+ Terminal Details .........................................	53
Configuring the Aprisa SR+ RF Network Details ......................................	53
Configuring the Aprisa SR+ Radio Settings ............................................	54
Command Line Interface .......................................................................	55
SNMP ..............................................................................................	55
LED Display Panel ...............................................................................	56
Normal Operation ........................................................................	56
Single Radio Software Upgrade.........................................................	57
Network Software Upgrade .............................................................	57
Test Mode .................................................................................	57

5. Applications ............................................................................	58
Basic point-to-multipoint application ........................................................	58
Advanced point-to-multipoint application with repeater .................................	59
Multi-interface point-to-multipoint application ............................................	60
Multi-hop Daisy Chain Repeaters in LBS Mode Application ................................	61
Pseudo Peer to Peer using Base-Repeater Application ....................................	62

Aprisa SR+ Product Description 1.3.0

	Contents	| ix
6.	Product Architecture.................................................................	63
	Product Operation ..............................................................................	63
	Physical Layer.............................................................................	63
	Data Link Layer / MAC layer ............................................................	63
	Channel Access ....................................................................	63
	Hop by Hop Transmission.........................................................	64
	Adaptive Coding Modulation .....................................................	65
	Network Layer ............................................................................	66
	Packet Routing.....................................................................	66
	Static IP Router ....................................................................	67
	Bridge Mode with VLAN Aware ..................................................	70
	VLAN Bridge Mode Description ..................................................	71
	Avoiding Narrow Band Radio Traffic Overloading....................................	73
	Product Architecture ...........................................................................	75
	Aprisa SR+ Radio Block Diagram........................................................	76
	Aprisa SR+ Protected Station Block Diagram .........................................	76
7.	Contact Us ..............................................................................	77

Aprisa SR+ Product Description 1.3.0

Introduction | 11

1.Introduction

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 packet data and Ethernet data between the base station, repeater stations and remote stations.

The Aprisa SR+ is configurable as a point-to-multipoint base station, a remote station or a repeater station.

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12 | Introduction

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 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 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.

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Introduction | 13

Store and Forward Repeater

The Aprisa SR+ in Repeater mode is used to link remote stations to the base station when direct communication is not possible due to terrain, distance, fade margin or other obstructions in the network. The following example depicts a repeater on the hill top to allow communication between the base station and the remote stations on the other side of hilly terrain.

Repeater Packet Forwarding

The Aprisa SR+ works in packet Store and Forward (S&F) for simple and low cost repeater network.

Repeater mode is available in both Access Request (AR) and Listen Before Send (LBS/CSMA) MAC operating modes. It allows a radio in Repeater mode to store a received packet and retransmit it.

Single Repeater Single Hop

The following example depicts an Aprisa SR+ single repeater single hop Store and Forward network.

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14 | Introduction

Multiple Repeater Single Hop

The following example depicts an Aprisa SR+ multiple repeater single hop store and forward network supporting both overlapping and non-overlapping coverage repeater networks. An overlapped RF coverage area creates radio interference and might affect network performance and reduce throughput, as show in figure (a), where Remote 1 is in overlapped RF coverage with Repeater 1 and Repeater 2.

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Introduction | 15

Multiple Repeater Multiple Hop

The following example depicts an Aprisa SR+ daisy chain multiple repeater multiple hop store and forward network i.e. multiple hops and multiple repeaters in non-overlapping RF coverage. The Aprisa SR+ daisy chain store and forward repeaters are currently supported in LBS MAC mode only.

In any type of store and forward repeater network base, repeater and remote radios must have their Tx/Rx frequencies sets to match to their appropriate linking devices as shown in the figures.

Note: Frequencies shown in the figures relates to the device on the left where {Tx, Rx} = {fx, fy}. In this example, the Base Station, Repeater 2 and remotes are deployed with Tx=f1 and Rx=f2. On the other hand Repeater 1 and Repeater 3 are deployed with Tx=f2 and Rx=f1, creating the required linking for daisy chain operation.

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16 | Introduction

Repeater Messaging

The Aprisa SR+ uses a routed protocol throughout the network whereby messages contain source and destination addresses. The remote and repeater stations will register with a base station. In networks with a repeater, the repeater must register with the base station before the remotes can register with the base station.

Additionally, based on destination address, messages are designated as either a ‘broadcast’ message, (mostly originating from a base station) or a ‘unicast’ message (mostly originating from a remote station).

In a network with a repeater, or multiple repeaters, the base station broadcasts a message which contains a source address and a destination address. The repeater receives the message and recognizes it is a broadcast message, from the destination address and re-broadcasts the message across the network. In IP routing mode 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 unicast destination address (the base station). The repeater will receive this message; recognize the destination address and forward it to the appropriate destination address.

In order to prevent repeater-repeater loops, a detection mechanism of ‘duplicate message’ and use of unicast messaging in remote to base/repeater direction is used.

For example, in the Multiple Repeater Single Hop figure above, the topology is of Base, Repeater 1, Repeater 2 and Remote 1 connected to Repeater 1 in overlapping coverage, where Remote 1 can also hear Repeater 2. When the Base station broadcasts a message, Remote1 will receive this message from both

Repeater 1 and Repeater 2 but will drop one of them as ‘duplicate message’. It is possible that Repeater 1, for example, can also hear the broadcast sent out by Repeater 2. In this case, Repeater 1 will drop this broadcast as a ‘duplicate message’.

These phenomena will not happen in the upstream direction as all messages are sent ‘unicast’. Remote 1 will send a packet to Base station, setting the destination address in packet to Base station and ‘next hop’ address in packet to Repeater 1. Thus, only Repeater 1 will forward the packet to Base station and

Repeater 2 will drop the packet as the ‘next hop’ address is not Repeater 2.

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Introduction | 17

Product Features

Functions

Point-to-Point (PTP) or Point-to-Multipoint (PMP) operation

Licensed frequency bands:

VHF 135	135-175 MHz
VHF 220	215-240 MHz
UHF 320	320-400 MHz
UHF 400	400-470 MHz
UHF 450	450-520 MHz
UHF 896	896-902 MHz
UHF 928	928-960 MHz

Channel sizes – software selectable:

12.5kHz 25 kHz 50 kHz

Adaptive Coding Modulation (ACM): QPSK to 64 QAM

Half duplex or full duplex RF operation

Ethernet data interface and RS-232 / RS-485 asynchronous multiple port options

Software selectable dual / single antenna port options (dual antenna port for external duplexers or filters)

Data encryption and authentication using 128,192 and 256 bit AES and CCM security standards

Terminal server operation for transporting RS-232 / RS-485 traffic over IP or Ethernet

IEEE 802.1Q VLAN support with single and double VLAN tagged and add/remove VLAN manipulation to adapt to the appropriate RTU / PLCs

QoS supports using IEEE 802.1p VLAN priority bits to prioritize and handle the VLAN / traffic types

QoS per port (Ethernet, serial, management)

L2/3/4 filtering for security and avoiding narrow band radio network overload

L3 Router mode with standard static IP route for simple routing network integration

L2 Bridge mode with VLAN aware for standard Industrial LAN integration

Ethernet header and IP/TCP / UDP ROCH header compression to increase the narrow band radio capacity

Ethernet and serial payload compression to increase the narrow band radio capacity

Pseudo peer to peer communication between remote stations through base-repeater or repeater stations

SuperVisor web management support for element and sub-network (base-repeater-remotes) management

SNMPv1/2/3 & encryption MIB supports for 4RF SNMP manager or third party SNMP agent network management

SNMPv3 context addressing for compressed SNMP access to remote stations

SNTP for accurate wide radio network time and date

Build-configuration / flexibility of serial and Ethernet interface ports (3+1, 2+2, 4+0)

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18 | Introduction

Radio and user interface redundancy (provided with Aprisa SR+ Protected Station)

Protected Station fully hot swappable and monitored hot standby

Transparent to all common SCADA protocols; e.g. Modbus, IEC 60870-5-101/104, DNP3 or similar

Complies with international standards, including ETSI, FCC, IC, ACMA, EMC, safety and environmental standards

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’

FIPS PUB 197, NIST SP 800-38C, IETF RFC3394, RFC3610 and IEEE P1711/P1689/P1685

FIPS 140-2: Security Requirements for Cryptographic Modules

The security features implemented are:

Data encryption

Counter Mode Encryption (CTR) using Advanced Encryption Standard (AES) 128, 192, 256 bit, based on FIPS PUB 197 AES encryption (using Rijndael version 3.0)

Data authentication

NIST SP 800-38C Cipher Block Chaining Message Authentication Code (CBC-MAC) based on RFC 3610 using Advanced Encryption Standard (AES)

Data payload security

CCM Counter with CBC-MAC integrity (NIST special publication 800-38C)

Secured management interface protects configuration

L2 / L3 / L4 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 provides recourse against interference

SNMPv3 with Encryption for NMS secure access

Secure USB software upgrade

Key Encryption Key (KEK) based on RFC 3394, for secure Over The Air Re-keying (OTAR) of encryption keys

User privilege allows the accessibility control of the different radio network users and the user permissions

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Introduction | 19

Performance

Typical deployment of 30 remote stations from one base station with a practical limit of a few hundred remote stations

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 SuperVisor with full configuration, diagnostics and monitoring functionality, including remote station configuration / diagnostics over the radio link

LED display for on-site diagnostics

Dedicated alarm port

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

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20 | Introduction

System Gain vs FEC Coding

This table shows the relationship between modulation, FEC coding, system gain, capacity and coverage.

Maximum FEC coding results in the highest system gain, the best coverage but the least capacity

Minimum FEC coding results in lower system gain, lower coverage but higher capacity

No FEC coding results in the lowest system gain, the lowest coverage but the highest capacity

This table defines the modulation order based on gross capacity:

Modulation	FEC Coding	Capacity
QPSK (High Gain)	Max Coded FEC	Minimum
QPSK (Low Gain)	Min Coded FEC
16QAM (High Gain)	Max Coded FEC
QPSK	No FEC
16QAM (Low Gain)	Min Coded FEC
16QAM	No FEC
64QAM (High Gain)	Max Coded FEC
64QAM (Low Gain)	Min Coded FEC	Maximum

This table defines the modulation order based on receiver sensitivity:

Modulation	FEC Coding	Coverage
QPSK (High Gain)	Max Coded FEC	Maximum
QPSK (Low Gain)	Min Coded FEC
16QAM (High Gain)	Max Coded FEC
QPSK	No FEC
16QAM (Low Gain)	Min Coded FEC
64QAM (High Gain)	Max Coded FEC
16QAM	No FEC
64QAM (Low Gain)	Min Coded FEC	Minimum

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Introduction | 21

Architecture

The Aprisa SR+ Architecture is based around a layered TCP/IP protocol stack:

Physical Proprietary wireless

RS-232 and Ethernet interfaces

Link

Proprietary wireless (channel access, ARQ, segmentation) VLAN aware Ethernet bridge

Network Standard IP

Proprietary automatic radio routing table population algorithm

Transport TCP, UDP

Application

HTTPS web management access through base station with proprietary management application software including management of remote stations over the radio link

SNMPv1/2/3 for network management application software

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22 | Introduction

Interfaces

Antenna Interface

2 x TNC, 50 ohm, female connectors

Single or dual antenna ports (with or without the use of external duplexer/filter)

Ethernet Interface

2, 3 or 4 ports 10/100 base-T Ethernet layer 2 switch using RJ45 Used for Ethernet user traffic and radio sub-network management.

RS-232 / RS-485 Interface

2, 1 or 0 RS-232 asynchronous ports using RJ45 connector

Optional 1x RS-232 or RS-485 asynchronous port using USB host port with USB to RS-232 or USB to RS-485 converters

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.

Protect Interface

1x Protect interface port

Used for the Protected Station operation.

Alarms Interface

1x Alarm port using RJ45 connector

Used to provide 2 x hardware alarm inputs and 2 x hardware alarm outputs

Aprisa SR+ Product Description 1.3.0