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TaitNet P25 Conventional Network with TB7300/TB9400 Base Stations for Simulcast System Overview [Enter Client Name]

TD-0037-06[Enter a client ID] Issue 6 July 2019

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of 36 TaitNet P25 Conventional Network with TB7300/TB9400 System Overview for Simulcast ▪ Issue 6

CONTACT INFORMATION

Tait Communications Corporate Head Office Tait International Limited P.O. Box 1645 Christchurch New Zealand For addresses and telephone numbers of regional offices, refer to http://www.taitradio.com.

COPYRIGHT AND TRADEMARKS

All information contained in this document is the property of Tait International Limited. All rights reserved. This manual may not, in whole or in part, be copied, photocopied, reproduced, translated, stored, or reduced to any electronic medium or machine-readable form, without prior written permission from Tait International Limited.

The word Tait and the Tait logo are trademarks of Tait International Limited.

All trade names referenced are the service mark, trademark or registered trademark of the respective manufacturers

PUBLICATION INFORMATION

While Tait has taken every care to ensure that the information and contents are correct and up-to-date at the time of publication, the information may contain technical inaccuracies and/or printing errors.

Tait does not guarantee the accuracy and correctness of the information. Tait cannot be held liable or responsible for errors or omissions in the contents of the technical documentation. All information contained in the technical documentation is given without any warranties or representations, expressed or implied.

http://www.taitradio.com/

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GLOSSARY AND DEFINITIONS

AAA Authentication, Authorization, and Accounting

ANI Automatic Number Identification

C4FM Continuous Four-level Frequency Modulation

DFSI Digital Fixed Station Interface

E&M Ear & Mouth

HTTP Hypertext Transfer (or Transport) Protocol

IP Internet Protocol

LAN Local Area Network

LSM Linear Simulcast Modulation

NMS Network Management System

NTP Network Time Protocol

RF Radio Frequency

SNMP Simple Network Management Protocol

WAN Wide Area Network


CONTENTS

CONTACT INFORMATION .................................................................................................................................. 2

TAIT COMMUNICATIONS CORPORATE HEAD OFFICE .................................................................................. 2

COPYRIGHT AND TRADEMARKS ...................................................................................................................... 2

PUBLICATION INFORMATION ............................................................................................................................ 2

GLOSSARY AND DEFINITIONS .......................................................................................................................... 3

LIST OF FIGURES ............................................................................................................................................... 5

1. INTRODUCTION ........................................................................................................................................ 6 1.1 The Basic Network .................................................................................................................................... 6 1.2 Tait P25 Conventional Base Stations ....................................................................................................... 8 1.3 Interface to DFSI Console ...................................................................................................................... 10 1.4 Interface to Analog Console ................................................................................................................... 11

2. NETWORK ELEMENTS ........................................................................................................................... 12 2.1 TB9400 Base Stations ............................................................................................................................ 12 2.2 TB7300 Base Stations ............................................................................................................................ 12 2.3 TB9400 Receive-only Base Stations ...................................................................................................... 13 2.4 GPS Timing Units ................................................................................................................................... 13 2.5 IP Backbone ........................................................................................................................................... 14 2.6 Mobile and Portable Radios.................................................................................................................... 16 2.7 Network Management System ............................................................................................................... 16 2.8 Digital Dispatch Console ......................................................................................................................... 16 2.9 RF Console ............................................................................................................................................. 16 2.10 Console Gateway ................................................................................................................................... 17

3. SIMULCAST OPERATION ....................................................................................................................... 19 3.1 Radio Calls ............................................................................................................................................. 20 3.2 Dispatch Console Calls ........................................................................................................................... 20 3.3 Central Voting Redundancy .................................................................................................................... 20 3.4 Linking ..................................................................................................................................................... 21 3.5 Performance under Failure Conditions ................................................................................................... 21

4. SYSTEM INTERFACES ........................................................................................................................... 22 4.1 DFSI ........................................................................................................................................................ 22 4.2 Console Gateway ................................................................................................................................... 23

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4.3 Digital Inputs ........................................................................................................................................... 23

5. SECURITY FEATURES ........................................................................................................................... 24 5.1 Centralized User Authentication (AAA) .................................................................................................. 24 5.2 Access to TB7300/TB9400 Base Stations ............................................................................................. 24 5.3 Access to Console Gateways ................................................................................................................. 24 5.4 Access to EnableMonitor ........................................................................................................................ 24 5.5 Encryption ............................................................................................................................................... 25 5.6 Remote Access ...................................................................................................................................... 25

6. MIGRATION FROM ANALOG TO P25 .................................................................................................... 26

7. MONITORING .......................................................................................................................................... 27 7.1 Network Management System ............................................................................................................... 27 7.2 Base Station Web UI .............................................................................................................................. 28

APPENDIX A: TB9400 BASE STATIONS .......................................................................................................... 29

APPENDIX B: TB7300 BASE STATIONS .......................................................................................................... 32

APPENDIX C: TN9110 P25 CONSOLE GATEWAY .......................................................................................... 33

APPENDIX D: SUPPORTED LICENSES .......................................................................................................... 35

LIST OF FIGURES Figure 1: P25 conventional network with three sites, two channels, a console gateway and an RF console ............. 7

Figure 2: Receive-only base stations ......................................................................................................................... 13

Figure 3: IP backbone ................................................................................................................................................ 15

Figure 4: RF console .................................................................................................................................................. 17

Figure 5: Console gateway ......................................................................................................................................... 17

Figure 6: Simulcast overlaps ...................................................................................................................................... 19

Figure 7: Radio calls ................................................................................................................................................... 20

Figure 8: Example of a DFSI console connection to a TB9400 ................................................................................. 22

Figure 9: System interfaces using console gateway .................................................................................................. 23

Figure 10: AAA authentication .................................................................................................................................... 24

Figure 11: Network Management System (NMS) ....................................................................................................... 27

Figure 12: TB7300 Base Station Web UI ................................................................................................................... 28


1. INTRODUCTION Tait TB7300 and TB9400 base stations provide a flexible platform offering Tait’s trusted reliability and performance. They form the basis of the Tait P25 conventional channels as well as P25 trunked channels. They also have voted and simulcast capability.

Common equipment and product flexibility provides a straightforward migration path between these network types.

This system overview focuses on the Tait P25 simulcast conventional channel operation. The P25 conventional functionality described here can also be used in non-simulcast channels—specifically in stand-alone repeater or line controlled base operation, or receiver voting configurations. This document also describes dual mode (analog and P25) conventional features and operation.

Simulcast transmission provides a means of achieving wide-area coverage with multiple transmitters utilizing a single frequency. In simulcast systems, audio is broadcast simultaneously over multiple transmitters on a single frequency. Essentially each transmitter in the system transmits the same signal, with the same characteristics, at the same time.

Simulcast is very useful because frequency allocations in many countries are problematic, and reusing the same frequency over a large area is cost-effective and sometimes the only possible way.

Tait Communications has decades of experience in private mobile radio systems and is well known for its TaitNet AS-IP solution with TB9400 or TB7300 (voted and simulcast channel in analog mode). For more information on AS-IP, refer to TD-0025-xx.

1.1 The Basic Network Similar to a Tait AS-IP network, a Tait P25 simulcast conventional network may include a number of sites. Each site can have several base stations (one per channel) linked via IP/Ethernet to form a local area network. The sites are linked through switches or routers by an IP backbone. For synchronization, each site also needs a GPS timing unit. The base stations across physical sites are grouped together to form channel groups. One of the base stations in each channel group is declared as the central voter (a function of the master base station) and the other base stations are its satellites. The central voter base station controls the operation of the channel group and performs central voting.

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Simulcast operation must be synchronized, which means the transmitters all transmit exactly in unison with each other, with slight adjustments to the launch times depending on the overlap zone. The central voter base station timestamps the voted voice signal to be transmitted and sends it to all channel group members. The timestamp tells members when to transmit each voice packet. Each channel group may use a console which can be either a digital dispatch console via DFSI, or dispatch console connected to the central site via a console gateway, or an RF console that is a mobile on a desktop. The DFSI interface connects the conventional base station or channel group to digital dispatch equipment and enables calls between the console and subscriber units. This DFSI interface may provide redundancy.

P25 conventional

dispatch console

IP b

ackb

one

CH1

CH2

GPS timing unit

Remote site 1 (Satellite)

CH1

CH2

GPS timing unit

Remote site 2 (Satellite)

CH1

CH2

Central site (Master)

Console gateway

CH1

CH2

RF console

CH2

CH1

GPS timing unit

Figure 1: P25 conventional network with three sites, two channels, a console gateway and an RF console

An AS-IP analog simulcast overlay can be added to a P25 conventional or P25 trunking solution—for example, for analog paging applications or legacy analog radio users such as mutual aid channels.


1.2 Tait P25 Conventional Base Stations Tait has three base stations supporting the P25 conventional mode: the TB7300, the TB9100 and the TB9400.

The subject of this overview is to describe P25 conventional networks with TB7300 and TB9400 base stations, and to explain the similarities and differences compared to the TB9100 base stations. • A non-simulcast, non-voted P25 conventional network can mix TB9100 and TB7300/TB9400 • For simulcast or voted P25 conventional network, a channel group can only have base stations of the same

type either all TB9100s, all TB7300s, or all TB9400s • For simulcast or voted P25 conventional network, the TB7300 and TB9400 support two types of channel group:

o the TB7300/TB9400 channel group with base stations at each physical site and o the console gateway channel group with only one TN9110 console gateway as the central voter and

the active central voter of the TB7300/TB9400 channel group as a satellite

The table provides a comparison of conventional system features between TB9100 and TB7300/TB9400, both analog (AS-IP) and P25.

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Feature TB9100 P25 Conventional Simulcast

TB7300/TB9400 Analog Simulcast

TB7300/TB9400 P25 Conventional Simulcast

Channel group size supported

Up to 60 TB9100 Tx / Rx or Rx and TN9110 console gateway provided that not more than 14 open the

receiver gate at the same time

20 TB73/9400 Tx / Rx or Rx (plus the console gateway channel group)

20 TB73/9400 Tx / Rx or Rx (plus the console gateway channel group)

Modulation P25 C4FM (simulcast) Analog FM (non-simulcast) dual mode (non-simulcast)

Analog FM (simulcast) P25 C4FM (simulcast) P25 LSM (simulcast)

dual mode (simulcast)

Management CSS windows application SNMP v2c

syslog

Web browser SNMP v2c, v3

syslog

Frequency bands (MHz)

B2 = 136 .. 156 B3 = 148 .. 174 H1 = 400 .. 440 H2 = 440 .. 480 H3 = 470 .. 520

K4 = Rx 794 .. 824, Tx 762 .. 870 L1 = 852 .. 930

B2 = 136 .. 156a B3 = 148 .. 174

H1 = 400 .. 440 a H2 = 440 .. 480 a H3 = 470 .. 520 H5 = 400 .. 470b

K4 = Rx 794 .. 824, Tx 762 .. 870

Transmit power 5W / 2x 50 W / 100 W TB7300 = 40/50 W

TB9400 = 2x 50 W / 100 W

Fill in receivers 6 per sub-rack 4 per sub-racka

Task manager Yes No

Sub-audible signalling CTCSS / DCS (four independent uplink / downlink) P25 NAC independent uplink / downlink

CTCSS / DCS (independent uplink / downlink)

NAC (independent uplink / downlink)

Redundant central voter

Yes Yes

Console options DFSI RF (trigger base)

Analog (E&M, tone remote)

Up to 3 DFSI (redundant) RF (trigger base)

Analog (E&M) on TB9400 E&M with optional interface PCB)

Analog (E&M, tone remote) – via console gateway.

Up to 3 DFSI (redundant) RF (trigger base)

Analog (E&M, tone remote) – via console

gateway.

Simplex support Yes Yes a. TB9400 only

b. TB7300 only


1.3 Interface to DFSI Console The DFSI functionality is licensed.

Feature TB9100 Dual Mode / P25 Conventional Simulcast

TB7300/TB9400 Dual Mode / P25 Conventional Simulcast

DFSI 1

This connection can also support control functionality.

3 (from version 3)

One of the connections is the primary connection and has control for operations such as channel change or change of repeat state. Two of the connections are called secondary, and have no control capability.

DFSI Duplex console operation Yes if the DFSI connection is on the central voter base station.

If the DFSI connection is on a satellite and if duplex console operation is needed, a duplex channel group is needed with twice the IP bandwidth than a normal channel group.

Yes (as the DFSI connection is on the central voter base station)

Console pre-empt RF Yes Yes

Encryption P25 only (not available in analog)

Yes transparent to base station

P25 only (not available in analog)

Yes transparent to base station

Base station control

(repeat, squelch, channel change)

Yes to all Yes to repeat and channel change

No to squelch

Active Connection To any member of the channel group To the central voter

Number per channel group As many as the members 3 (from version 2.55)

Redundancy No (but many active DFSI can be used for a similar result)

Yes if the backup central voters have the DFSI license and are configured for DFSI.

In a TB7300 or TB9400 channel group, more than one base station can have the DFSI interface enabled but only the central voter base station DFSI interface will operate. In case of a change of central voter base station, the new central voter base station will start operating its DFSI interface (if licensed). It is recommended that the console sub-system has a list with all the potential DFSI interfaces and search for the active one.

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1.4 Interface to Analog Console Feature TB9100 Dual Mode / P25

Conventional Simulcast

TB7300/TB9400 Dual Mode / P25

Conventional Simulcast

Signaling types E&M

Tone-remote keying

Limited E&M

Tone-remote keying

Console ANI MDC 1200 transparent in analog and P25

MDC1200 <-> P25

MDC 1200 transparent in analog

MDC1200 <-> P25

Duplex console operation Yes, if the TN9110 the analog console is connected to is a standalone base station with analog line connectivity.

Yes, if the TN9110 the analog console is connected to is the central voter (in case of channel group).

Yes, if the TN9110 the analog console is connected to is a satellite and if all the gateways and base stations with analog line connections are configured as duplex in their channel group profiles.

Yes, if the TN9110, that is the central voter of the console gateway channel group, is configured as duplex in its channel group profile.

Console pre-empt RF Yes Yes

Encryption P25 only (not available in analog)

Yes P25 encryption end-point

P25 only (not available in analog)

No but the console gateway if included the P25 conventional network with TB9400 can act as an encryption end-point

Base station control

(repeat, squelch, channel change)

Yes No


2. NETWORK ELEMENTS A P25 conventional simulcast channel contains the following network elements.

2.1 TB9400 Base Stations TB9400 base stations provide:

• RF channels. Each 4U subrack has one or two reciters (modules providing a receiver and an exciter). Each reciter and power amplifier combination provides one frequency pair.

• Analog conventional mode, P25 conventional mode, dual mode conventional (analog, P25) and P25 trunking mode

• Built-in intelligent voting, used in simulcast

• DFSI connection for digital dispatch console in analog, P25 conventional and dual mode

• Analog line connectivity for analog dispatch console in analog mode only

• Selection of local repeat or channel group operation by NAC or subaudible tones

• Controlled operation when the base station is isolated from the channel group

• Ability to use a TN9110 console gateway to provide connectivity to an analog console

• Remote management from a computer using a web-based application

The TB9400 base station provides digital inputs that can be used for general purposes, such as the monitoring of site access doors. The base station can be set up to generate alarms to an SNMP manager or the base station’s web application.

For more information about the TB9400 base station, see Appendix A.

2.2 TB7300 Base Stations TB7300 base stations provide:

• RF channels. Each 4U subrack has one or two reciters (modules providing a receiver and an exciter). Each reciter and power amplifier combination provides one frequency pair.

• Analog conventional mode, P25 conventional mode, dual mode conventional (analog, P25), AS-IP, DMR conventional (Tier 2), DMR trunked (Tier 3) and MPT

• Built-in intelligent voting, used in simulcast

• DFSI connection for digital dispatch console in analog, P25 conventional and dual mode

• Analog line connectivity for analog dispatch console in analog mode only

• Selection of local repeat or channel group operation by NAC or subaudible tones

• Controlled operation when the base station is isolated from the channel group

• Ability to use a TN9110 console gateway to provide connectivity to an analog console

• Remote management from a computer using a web-based application

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For more information about the TB7300 base station, see Appendix B.

2.3 TB9400 Receive-only Base Stations Mobile and portable radios transmit at a lower power than base stations. In order to improve RF coverage of the RF channels, fill-in receiver sites can be used. Each 4U subrack has one to four receiver modules.

Tx/Rx base station Rx-only base station

IP backbone

Figure 2: Receive-only base stations

TB9400 receive-only base stations accept the same configuration file as the fully featured TB9400 base stations to provide a simple configuration management of the system. The TB9400 channel group votes fill-in receivers and transceivers as part of normal channel group operation.

Note: a standard TB7300 or TB9400 reciter may be used as receive only by disabling the transmitter in the configuration. When in this setup, the reciter does not need a PA module.

2.4 GPS Timing Units Simulcast operation requires a GPS timing unit at each site, providing an external frequency reference, 1 PPS signal, and an NTP server. The 1 PPS timing pulse and NTP must be GPS disciplined, and ensure that simulcast transmissions from each physical site in the channel group are aligned with microsecond precision. The NTP server provides time-of-day, the 1PPS signal provides the precise second boundary and the external frequency reference enables counting the number of ticks from the last 1PPS signal.

The console gateway, if used, and any other IP connected third-party should also be connected to NTP in order to align log timestamps.

Features:

• 800 MHz base stations must have a 0.1 ppm external frequency reference source, to ensure the accuracy of the transmit frequency

• NTP maintains simulcast time-of-day, and is also used for accurate time stamping of the logs

• Tait recommends using the Spectracom SecureSync synchronization system, which can provide a 1 PPS signal and a frequency reference, as well as NTP


• One GPS timing unit connector can support up to eight daisy-chained TB9400 base stations

• Fill-in receivers only need NTP for log alignment purposes or if (against recommendation) it is to be used as central voter for simulcast (then needs 1PPS and external reference). The NTP may be sourced via the IP network.

2.5 IP Backbone The IP backbone connects the various elements of the network. TaitNet equipment can use any COTS IP based network fabric. TaitNet equipment is not sensitive to the network type or configuration, but traffic integrity, voice quality, security, are consequences of those choices.

Overall, the network must provide for user audio, user data, signaling, and management. Networks links must be sufficiently well provisioned, with QoS management to ensure a user experience with good-quality speech.

Networks may be switched, routed, VLANed, and firewalled.

The appropriate security precautions (firewalling, VPN) should be applied to any interface to other networks (company LAN, public Internet).

The public Internet itself is generally not suited to provide the backbone as it cannot guarantee performance or provide a high level of security.

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Central site

Remote site 1

Network Management System

Base stations

Base stations

IP

IP

IP

GPS timing unit

Remote site 2

Base stations

GPS timing unit

GPS timing unit

Firewall

P25 conventional

dispatch consoles

Console gateways

IP

Organization’s LAN

database

Dedicated IP backbone

RF Link

Figure 3: IP backbone

Various physical links can be used in the backbone, including microwave, DSL, E1/T1, MiMOMax narrowband wireless, leased line, and fiber-optic cable. The link must provide Ethernet interfaces at each end and meet bandwidth, latency, jitter and quality of service (QoS) requirements.

Depending on the topology, remote sites may need to be linked using a high-bandwidth, low-latency RF link infrastructure, such as MiMOMax Tornado. The data bandwidth of the link depends on the selected frequency RF link. For more information, refer to the specifications on www.mimomax.com.

http://www.mimomax.com/


2.6 Mobile and Portable Radios Tait radios are designed with simple user interfaces and flexible group configurations, allowing users to maintain reliable communications within their team and also to other teams or individuals when required. Tait radios are built for durability.

If an organization plans to use the TaitNet P25 conventional system as a basis for eventual migration to a P25 Phase 2 system, Tait recommends the TM9400 and TP9400 series of subscriber units which support a large range of modes: analog, dual mode, P25 conventional, P25 Phase1, and P25 Phase 2 Trunking. TB9400 base stations support analog, dual and P25 conventional operation (simulcast and non-simulcast) and P25 Phase 1 and Phase 2 trunking. TB7300 base stations support dual and P25 conventional operation (simulcast and non-simulcast), AS-IP, DMR conventional (Tier 2) and DMR trunked (Tier 3), and MPT. This is important for interoperability with other vendors and also for working with other agencies that may have a different system.

Radios of both the TM9000 and TP9000 series can be managed using the Tait EnableFleet application. This allows for the management of installation information and for the updating of configuration and firmware. The P25 conventional system doesn’t provide over-the-air programming so any updates are made using the wired EnableFleet client. For more information, please see the system overview document of the Tait Enable suite (TD-0004).

2.7 Network Management System TaitNet P25 conventional networks support an SNMP-based network management system (NMS) such as Tait EnableMonitor. For more information, see section 7.1. Tait recommends that all supporting equipment (such as RF links, switches) support SNMP.

2.8 Digital Dispatch Console Through the integration third-party equipment and software, dual mode or P25 conventional networks with TB7300 or TB9400 can optionally provide additional capabilities such as dispatch integration.

Tait has partnered with Omnitronics, Avtec and Zetron to provide a range of digital dispatch solutions.

In its Global Solution Partner Program, Tait has an extensive partner network and highly developed processes that enable us to be responsive in innovative ways to rapidly create turn-key solutions.

Console solutions include Omnitronics RediTALK-Flex and DX-Altus, Avtec Scout, and Zetron Acom and MAX. Contact Tait for more information.

2.9 RF Console Depending on the type of network and the possible migration path, Tait recommends the use of TM9400 mobile radios as RF consoles of channel groups on small systems.

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RF console

Custom dispatch

application

RS-232

CCDI/API

Figure 4: RF console

Customers have the ability to create their own dispatch solution using the CCDI or API protocol features available with these radios. For more information visit www.taitradio.com and search for the API Protocol manuals on the Technical Resources website.

2.10 Console Gateway The console gateway supports P25 conventional and analog for migration to P25 conventional.

The console gateway consists of a gateway module in a subrack, optionally with a PMU. A subrack can contain several gateway modules. The console gateway’s analog line connects to the dispatch system, and its Ethernet interface connects to the IP backbone of the P25 conventional network with TB7300 or TB9400. It has no RF functionality.

P25 conventional

dispatch console

IP b

ackb

one

Remote site 1

CH1

Central site

Console gateway

CH1

GPS timing unit

Remote site 2

Switch/router

Analog I/O(E&M)

Figure 5: Console gateway

The console gateway can be managed remotely from a PC using a Windows application called the Customer Service Software (CSS). The Tait console gateway supports any type of analog console using the E&M, a subset of the tone remote control signaling, and analog inputs and outputs.

A unique console gateway is supported by the central voter base station. In case of redundant console gateway, contact Tait for possible configuration.

The signaling schemes used on the analog line with analog consoles are MDC1200, tone remote and E&M. Most subscriber signaling is passed over the analog line as MDC1200. Where MDC1200 is not available, a dispatcher can use tone remote signaling for transceiver operation which allows calling profiles to be selected for digital P25 calls that specify an individual or group address and a sender ID.

http://www.taitradio.com/


For more information on the console gateway, see Appendix C.

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3. SIMULCAST OPERATION In a simulcast network, audio is broadcast:

• simultaneously by multiple transmitters

• using a single frequency

• over a wide area

The received voice signals from all TB7300/TB9400 base stations of a channel group are forwarded to the central voter, which uses highly sophisticated algorithms to create the best composite RF signal for retransmission. The voter then sends the signal, time-stamped using the timing signal of the GPS timing unit, to all base stations. IP latency will result in variable arrival times at the base stations. Timestamps guarantee that the signals are launched simultaneously from the base stations. Coverage overlaps can be optimized with slight adjustments to the launch times. See the relevant Tait system manual for further information.

Site 1Coverage overlap

Site 2

IP backbone

Voter

Figure 6: Simulcast overlaps

Sites of a simulcast network are usually located close together to provide good coverage allowing users to move seamlessly between sites without having to change the channel.

In areas where one signal is significantly stronger than other signals, the mobile and portable radio will capture the strongest received signal. Other lower-strength signals will not be heard.

In overlap areas, the radio receives two or more RF signals which could corrupt each other. Simulcast reduces this effect by ensuring the transmissions arrive at the radio at the same time, reinforcing, rather than corrupting each other.


3.1 Radio Calls When a radio transmits, more than one base station (cell) may receive the signal. Each base station receiving the signal sends it to the central site (the central voter base station). There a central voter creates a composite signal and then sends it, time-stamped for synchronization, to all base stations. The base stations transmit the call with the same characteristics at a known time to reach the overlap area at the same time.

Radios Base stations Central voter

Site 2

Site 1RF IP

Rx

Site 2

Site 1RF IP

Tx

Figure 7: Radio calls

NAC subaudible signaling provides a squelch function so radio users only hear other radios with the same signaling.

Radios can be programmed with channels that bypass the radio network and communicate directly with one another. This can be useful for geographically limited incidents such as local emergencies, or as a fall-back solution in case of a partial or complete network failure.

3.2 Dispatch Console Calls Calls from a line connected (analog or IP) dispatch console take priority over radio calls. If a dispatch call is initiated while a radio is transmitting, radio users hear the dispatch audio, not the radio user. The console user can hear the radio user even while talking (duplex audio on the dispatch interface).

Digital dispatch console connected via the DFSI to the TB7300/TB9400 (in analog, dual mode or P25) can manage the channel group. It can control the RF repeat as well as the change of channel across the channel group, it is recommended in this scenario for all the base station of the channel group to have similar configurations of channels. It also receives voter reports from the central voter.

3.3 Central Voting Redundancy Because each base station has a built-in voting capability, eliminating a single point of failure in a simulcast channel group is straightforward. The most centrally located site generally handles the voting and simulcast control, but other sites can easily be configured to take over these functions should that site fail. No additional hardware is required. The DFSI interface follows the same principle and can be operational on any central voter.

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3.4 Linking The linking requirements include user, control, and management traffic. The management bandwidth requirements are the same for all technologies.

Any central voter needs enough linking capacity to handle the traffic from all receiving satellites. This applies also to a backup central voter.

Please contact your Tait representative for more information.

3.5 Performance under Failure Conditions The TaitNet P25 conventional network has multiple strategies for continuing to provide service under failure conditions. Its architecture gives it a tolerance of failure as single points of failure can be avoided.

The following table details the effect of different failures.

If this fails... Then...

Satellite base station in a simulcast channel group

The channel group is still working but the base station’s physical site does not contribute to coverage.

Link between satellite base station and channel group

The channel group is still working but this base station does not contribute to the overall coverage. The isolated base station’s physical site can either become a central voter of its own channel group and operate locally (with the right license) or it can be declared unsynchronized and depending on the configuration can or cannot transmit.

Central Voter base station in a simulcast channel group

If there is a backup central voter base station, it takes over the central voter role. If there is only one central voter-capable base station in the TB9400 channel group, the whole channel group won’t be operational. If the DFSI license is available on the backup central voter, the DFSI interface will become operational. If a console gateway is used in the system and if there is a backup central voter base station, then the new central voter base station will become a member of the console gateway channel group.

1 PPS timing signal in a Phase 1 system

The GPS timing unit has a holdover period, which means that if the GPS fix is lost in a simulcast system, the GPS timing unit will continue to send 1PPS timing. After the holdover time, all base stations of that site lose the 1PPS signal and are immediately unsynchronized. Base stations in a simulcast channel group can be configured to transmit or not to transmit after they become unsynchronized. If they do transmit, coverage and signal quality may become degraded in overlap zones over a period of time.

1 PPS and GPS timing unit loss at one entire physical site

The site has lost synchronization so cannot operate in simulcast. The base stations at the site will not transmit. (In the United States, if the transmitters are 800 MHz, the system may contravene US law if it continues to operate for an extended period of time in a known unsynchronized state.)

Base station Radios can still operate in direct mode (see Radio Calls).

EnableMonitor Central monitoring of the network is not available. Maintainers can still monitor base stations. Syslog messages can still be sent to syslog collectors.

Console gateway The central voter supports a unique console gateway in its own channel group. If the console gateway fails, then the analog line connecting to the analog dispatch console is lost and the P25 conventional group will be without a dispatch console.


4. SYSTEM INTERFACES

4.1 DFSI The DFSI interface allows a dispatcher to view and exercise control over a channel group, for example by seeing which receivers are active and which receiver wins the vote.

The interface allows a digital console, which is important for the different modes of operation (single TB9400, voted TB9400 group, and simulcast channel group), or a voice recorder to be connected to the TB9400. This interface is available in analog, dual mode and P25 conventional.

TB9400 DFSI supports:

• Traffic: Voice and supplementary services

• Channel control: repeat, change channel, squelch

• Analog and digital transmission

The TB9400 supports up to three DFSI devices:

One connection for traffic and channel control called the primary DFSI

Two secondary connections for traffic only

These three interfaces are independent and any of them can be used.

For DFSI redundancy of the primary connection, it is recommended to have the two DFSI compliant consoles configured on the primary DFSI. The TB9400 will connect to the first one and if the connection to the first DFSI device fails, the TB9400 will connect to the second device automatically.

P25 conventional

dispatch consoleCH1

Site GPS timing unit

Switch/router

CH2CH1

Third-party voice recorder

Site door

database

E-mail/Base station application/SNMP

IP backbone

Custom alarm via IO

DFSI

Figure 8: Example of a DFSI console connection to a TB9400

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4.2 Console Gateway The console gateway provides an interface to the dual mode and P25 conventional network by means of an analog 4-wire E&M connection which uses a 4-wire (2-pair) transmission path for the voice signal.

The E&M interface can be used to connect an analog dispatch console or a paging console. Any other third-party devices such as voice recorders need to be connected through the console or through a mobile radio.

P25 conventional

dispatch console

CH1

Site

Console gateway 1

GPS timing unit

Switch/router

4-wire E&M

CH2

Console gateway 2

Paging console

CH2

4-wire E&M

CH1

Third-party voice recorder

Site door

database

E-mail/Base station application/SNMP

IP backbone

Custom alarm via IO

Figure 9: System interfaces using console gateway

4.3 Digital Inputs The TB7300 or TB9400 base station provides digital inputs which can be used for general purposes, such as the monitoring of site access doors. The base station can be set up to generate alarms to an SNMP manager or the base station’s web application. Some digital inputs may have other uses in relation to the analog line functionality (e.g. receive disable) or to the simplex functionality. Check the Tait Base Station Features Overview (TD-0047-xx) for further information.


5. SECURITY FEATURES

5.1 Centralized User Authentication (AAA) TaitNet conventional networks can be set up with an AAA server to provide centralized user authentication for all logins to the TB7300 or TB9400 base stations. LDAP and Radius protocols are supported. When users attempt to connect to a network element, that element passes the request to the AAA server, which replies indicating whether the user has permission and what the level of access should be. If a Radius server is used, passwords are always encrypted.

Network users (maintainers and administrators)

AS-IP network AAA server and user directory

Login/password

Access granted/denied

Authentication request

Authentication response

database

Figure 10: AAA authentication

Centralized user authentication creates an audit trail of all login attempts in a single log. A user’s credentials can be revoked quickly and easily if they become compromised. Even with centralized user authentication, Tait equipment still requires one locally authenticated user for access to remain possible in case the AAA server fails or loses connection. That user’s name and password should not be used routinely.

5.2 Access to TB7300/TB9400 Base Stations Web-based browser access to the base station is protected by HTTPS. Users only gain access through a user name and password. The base station also supports centralized user authentication (AAA). The base station supports multiple access levels, so users can be restricted to monitoring only or can be permitted to change base station configurations and carry out diagnostic tests. Only those with Administrator level can add or modify the accounts of other users.

5.3 Access to Console Gateways The console gateway itself and its Customer Service Software (CSS) are both password-protected. Both protections are optional. The gateway supports multiple access levels, so users can be restricted to monitoring only or be permitted to change gateway configurations and carry out diagnostic tests. A CSS user can give the gateway a password. The CSS then optionally remembers the password. Each time you connect to the gateway, the CSS must authenticate itself to the gateway. The console gateway doesn’t provide centralized user authentication (AAA).

5.4 Access to EnableMonitor All parts of EnableMonitor provide secured access to data. As a minimum, access is provided through a username-password pair. Access to all databases is logged against the user and a basic activity record is kept to allow a degree of forensic examination after network events.

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5.5 Encryption P25 calls can be encrypted. The P25 conventional network supported end -to-end encryption. The TB7300/TB9400 base stations pass the encrypted calls transparently in the channel group, to the digital dispatch console via DFSI or to a console gateway with analog line connectivity. The digital dispatch console is responsible for decrypting/encrypting the calls. In general, encrypted audio quality is indistinguishable from unencrypted audio. However there may be situations where encrypted audio experiences more degradation than unencrypted audio due to the additional overhead of the encryption key identifier.

When an analog line is necessary, the console gateway performs P25 encryption and decryption. The console gateway supports Project 25 compliant DES (via the basic encryption license) and AES (Advanced Encryption Standard) with the AES license.

5.6 Remote Access The network can be set up with secure remote access for use by authorized support personnel or by on-call network administrators working from home. Tait offers several tiers of service contract that can provide remote technical support of the network. Contact Tait for further details.


6. MIGRATION FROM ANALOG TO P25 Migration is made easier by the common equipment practice and feature sets among TB9400 analog, dual mode and P25 conventional channels and P25 trunked channels.

Things to think about when migrating a network are:

• The simulcast modulations analog FM, C4FM, LSM, and HDQPSK do not have the same delay spread characteristics, thus the possible site separation is different for different channel types. Upgrading a simulcast channel may require additional sites to achieve the same coverage.

• Changing the modulation type on a TB9400 base station is a straightforward configuration change. TB9400 base stations making up a simulcast channel group must have the same software version and compatible channel settings to work as a simulcast channel.

• TB7300 base stations are capable of both P25 and DMR functionality via a simple configuration change. TB7300 base stations making up a simulcast channel group must have the same software version and compatible channel settings to work as a simulcast channel.

• A conventional overlay channel can be a good way of verifying RF operation without the complexity associated with a trunked network

• Refer to the feature list in section 2.1 for a detailed feature breakdown and comparison among channel types

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7. MONITORING The TB7300/TB9400 provides two main means of monitoring:

• SNMP-based Network Management System (NMS) of network elements

• the base station’s web UI to monitor the base station’s performance

7.1 Network Management System TB7300/TB9400 networks support an SNMP-based network management system (NMS) such as Tait EnableMonitor. EnableMonitor communicates with devices on the network using SNMP and delivers a range of core functions useful for managing the network.

EnableMonitor sends polls to configured devices and receives SNMP messages from all the devices on the network (including 3rd party equipment), storing them in its database. Each monitored device has a software process called an SNMP agent that handles these messages. Maintainers can access the NMS locally or remotely using a web browser.

base station

WANMicrowave linking

NMS

Maintainer’s computer

SNMP agent

SNMP agent

IP switchMicrowave linking

SNMP agent

GPS timing unit

database

Web browser

Console gateway

SNMP agent

SNMP agentRouter/switch

Remote access

Figure 11: Network Management System (NMS)

EnableMonitor can check whether a device is present, receive syslog messages, store them in a daily file and email the duty maintainer when a problem occurs.

For more information on EnableMonitor, please see the system overview document of the Tait Enable suite (TD-0004).


7.2 Base Station Web UI The web UI of the TB7300 or TB9400 base station allows monitoring of a wide range of performance parameters and the digital input/output line.

Figure 12: TB7300 Base Station Web UI

The base station can be configured to trigger alarms when a configured parameter crosses a defined threshold. Some thresholds are fixed, being part of the firmware. Depending on their severity, alarms are reported to the internal log, the syslog and the SNMP manager.

The online help of the base station provides detailed information about all fields and parameters.

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APPENDIX A: TB9400 BASE STATIONS The TB9400 Base Station/Repeater provides excellent analog conventional or P25 digital repeater performance and conforms to the Project 25 digital TIA standards.

It has the following key features:

IP Connectivity The base station uses its IP connection for voice and data, and control signaling and monitoring, making for efficient network design and easy scaling.

Modular Design The base station consists of a separate reciter, PA and PMU, making for easy installation, customization and maintenance. These modules come in different variants depending, for example, on the RF band or the supply voltage. Each module is inserted into the subrack from the front and is secured at the front with a metal clamp. Both clamp and module are easily removed for rapid module replacement.

Built-in Intelligent Voting In both simulcast and non-simulcast channels, the central voter base station uses its built-in voting facility to compare the received signals, selecting the best quality signal for transmission by the wide area simulcast channel. No external voter is required. Providing a backup voter is straightforward.

Remote Management The base stations can be managed remotely from a PC or workstation, including, for example, the following:

• Alarm monitoring and management

• Fault diagnosis

• Configuration

• Firmware downloads

The TB9400 has a web-based management interface.

Support for Integrated Network Management The base stations have detailed MIBs, enabling EnableMonitor or other SNMP-based network managers to monitor base station operation along with all the other devices making up the network.


Power Supply Options A Power Management Unit (PMU) can be supplied with any of the options below:

• 88 V to 264 V AC

• 12 V, 24 V or 48 VDC

• AC / DC with auto-changeover

Connections The base station uses no backplane PCB or rear inter-module wiring. This allows modules to be installed in a range of hardware configurations according to your requirements. All internal wiring between modules is behind the front panel in a tidy cable tray. At the rear of the base station, you have only the connections that are required to connect to a radio system to allow for clean and tidy installation.

Linear Simulcast Modulation The TB9400 supports LSM for simulcast operation, enabling simulcast networks to have fewer physical sites.

Phase 2 Upgradable The TB9400 hardware supports P25 Phase 2 operation.

Frequency Bands The TB9400 is available in the following frequency bands:

Frequency identification

Frequency band and sub-band 50 W 100 W Receive

only

VHF B band B2 = 136 MHz to 156 MHz B3 = 148 MHz to 174 MHz

✔ ✔ ✔

UHF H band HH = 378 MHz to 420 MHz H1 = 400 MHz to 440 MHz H2 = 440 MHz to 480 MHz H3 = 470 MHz to 520 MHz

✔ ✔ ✔

700/800 MHz K band K4 = 762 MHz to 870 MHz (transmit: 762 MHz to 776 MHz and 850 MHz to 870 MHz, receive: 792 MHz to 824 MHz)

✔ ✔ ✔

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Improved Firmware Upgrade Upgrading firmware in a TB9400 is a two-stage process that minimizes disruption to the network. The new firmware can be remotely uploaded at any time without affecting network operation. This allows all base stations to have their firmware uploaded prior to the switchover. The TB9400 retains the previous firmware version in case a decision to revert is made.

Front Panel LCD Display and Keypad The front panel interface has a large LCD display, four status indicator LEDs, and a keypad for navigating the menus provided on the display. It allows a basic level of local monitoring and control without the use of a PC but can be locked if required. You can for example: optionally display and enter the IP address and network identity see from the alarm LED whether any alarms are active

More Information For more information, please ask for the TB9400 Specifications Manual (MBC-00002).


APPENDIX B: TB7300 BASE STATIONS The TB7300 Base Station/Repeater has a 1U form factor with a 12V power supply, and no front panel LCD or keypad. It provides an air interface capable of: P25 conventional Dual conventional ASIP DMR conventional (Tier 2) DMR trunked (Tier 3) MPT

Frequency Bands The TB7300 is available in the following frequency bands:

Frequency identification

Frequency band and sub-band 40 W 50 W

VHF B band B3 = 148 MHz to 174 MHz X ✔

UHF H band H3 = 470 MHz to 520 MHza H5 = 400 MHz to 470 MHz

✔ X

a. H3 band is not supported by P25 air interface operation

Note: Transmit powers are defined in MBD-00002-xx TB7300 Base Station/Repeater Specifications Manual.

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APPENDIX C: TN9110 P25 CONSOLE GATEWAY The Tait P25 console gateway has the following key features:

IP Connectivity The console gateway uses its IP connection for voice and data, and control signaling and monitoring, making for efficient network design and easy scaling.

Modular Design The console gateway consists of a separate gateway module and PMU, making for easy installation, customization and maintenance. Each module is inserted into the subrack from the front and is secured at the front with a metal clamp. Both clamp and module are easily removed for rapid module replacement.

Interfaces The console gateway provides the following connectivity to a dispatch console:

• 4-wire E&M and analog

• DFSI (Tait recommends using the native DFSI interface on TB9400)

• Switching between MDC1200 and P25.

Remote Management The console gateway can be managed remotely from a PC or workstation, including for example the following:

• Alarm monitoring and management

• Fault diagnosis

• Configuration

• Firmware download

The console gateway uses the Customer Service Software (CSS), a Windows-based application.

Support for Integrated Network Management The console gateway has detailed MIBs, enabling EnableMonitor or other SNMP-based network managers to monitor base station operation, along with all the other devices making up the network.


Power Supply Options A Power Management Unit (PMU) can be supplied as any of the options below:

• 88 V to 264 V AC

• 12 V, 24 V or 48 VDC

• AC / DC with auto-changeover

In addition, the console gateway can operate from 12 V DC with no PMU.

Connections The console gateway uses no backplane PCB or rear inter-module wiring. This allows modules to be installed in a range of hardware configurations according to requirements. All internal wiring between modules is behind the front panel in a tidy cable tray. At the rear of the console gateway, you have only the connections that are required to allow for clean and tidy installation.

More Information For more information, please ask for the TB9100/P25 CG/P25 TAG Specifications Manual (MBA-00014).

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APPENDIX D: SUPPORTED LICENSES

Licenses The following licenses will be required for the TaitNet P25 Conventional Simulcast LSM TB9400 system to operate:

TB7300/TB9400 Base Station License (SFE) License description Central

Voter Backup Central Voter

Satellite Satellite Receive only

TBAS041 (per default)1 Analog Air Interface ✔ ✔ ✔ ✔

TBAS050 CAI (Common Air Interface) ✔ ✔ ✔

TBAS050—RO CAI Receive Only ✔

TBAS061 Central Voter ✔ ✔

TBAS071 IP Networking Satellite ✔

TBAS071—RO IP Networking Satellite ✔

Options

TBAS060 Digital Fixed Station Interface ✔ ✔

TBAS062 Simulcast Enable (C4FM Modulation)

✔ ✔ ✔

TBAS0652 LSM (Linear Simulcast Modulation)

✔* ✔* ✔*

1 Per default: the license is supplied with the equipment and doesn’t need to be ordered. 2 TBAS062 is a prerequisite to TBAS065.


TN9110 Console Gateway License (SFE) License description Console

Gateway

TBAS000 (per default) Default Radio System ✔

TBAS059 (per default) SNMP ✔

Options

TBAS051 Analog line ✔

TBAS057 Base encryption ✔

TBAS061 Central Voter ✔

Support Limitations A site does not have any limits of channel support as long as the IP links, the power, the RF equipment (such as combiners) and the synchronization signals are provided.

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