P25 TRUNKED SYSTEM OVERVIEW

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1 P25 TRUNKED SYSTEM OVERVIEWWhen discussing an overall P25 Trunked network of systems, three basic terms are important

to the overall understanding of the system:

Site

Region

Network

A P25 Trunked Site refers to the radio equipment located at a tower site. This may include up

to twenty-four MASTR III RF base stations and a Site Interface cabinet. MASTR III base

stations provide the RF radio backbone for the site and the Site Interface cabinet houses the

data management equipment.

Regions are formed when two or more P25 Trunked Sites are connected to a Network

Switching Center (NSC). A NSC provides a centralized management point for the sites within

the region.

A Network is formed when two or more Regions are connected to a Network Operations

Center (NOC) and provides a centralized management point for the entire Network ofRegions.

1.1 MASTR III P25 TRUNKED SITE

The M/A-COM P25 Trunked Site is a high-performance radio communications system

available in VHF and UHF frequency bands with a wide variety of configurations to meet

critical communications requirements for present and future communication needs. The

MASTR III P25 Trunked Site is a highly reliable trunked radio communications system with

a unique architecture that ensures continued operation even under failure conditions. The

MASTR III P25 Trunked infrastructure is based on an industry standard Ethernet architecture

capable of linking multiple RF sites to console controllers and system management devices.

The MASTR III P25 Trunked infrastructure makes use of the industry standard InternetProtocol (IP) over an Ethernet backbone to provide fast, highly reliable and fault-tolerant

management and control communications. Cisco Ethernet switches and routers provide the

connectivity previously provided by serial links. Wide Area Network (WAN) technology

connects the 100 MB Ethernet LAN to the RF sites, dispatch consoles, other data

management locations, etc. Figure 1-1 gives an example of a 5-channel site. Options and

accessories may vary from those represented in Figure 1-1.

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Figure 1-1: Example of a Five Channel MASTR III P25 Trunked RF Site

The MASTR III-P25T base station is the radio backbone for P25 Trunked site configurations.

A P25 Trunked site comprises two or more MASTR III P25 Trunked RF base stations and

supporting hardware. This architecture is portrayed in Figure 5-2 where hardware shown in

the upper portion of the pictorial represents the RF Radio Communication devices while thelower portion of the pictorial shows the Local Area Network (LAN) system and a network of

site management and data communication devices.

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Tranking RepeaterMASTRIII

Sure Call

Ethernet Switch

SiteLinkMain and Back-up

SitePro MMM

NetworkSentry

Router


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Figure 1-2: P25T RF Site Overview

The MASTR III P25 Trunked base station functions much like the traditional MASTR III

base station providing over-the-air transmit and receive paths, with the addition of a DSP card

located in the MASTR III T/R shelf to encode and decode the P25 TX/RX modes of

operation. However, unlike traditional MASTR III stations, P25 Trunked configurations only

support P25 modulation modes of operation. No analog voice paths are provisioned withMASTR III P25 Trunked base station configurations.

1.2 P25 TRUNKED REGION

Regions are formed when two or more P25 Trunked RF Sites are networked together via IP-

based Routers (see Figure 5-3) to the NSC. Regions consist of a minimum of two RF sites and

a NSC. Regions may also be equipped with multiple Communications Console Controllers

and redundant hot standby NSC components to provide one the most reliable trunked

communication backbones available

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Figure 1-3: Example of an P25 Trunked Region

1.3 Network Switching Center

The Network Switching Center is a management system built on software platforms residing

on two or more Personal Computers. The NSC concept minimizes overall hardware

requirements by relying on software driven management and processing applications. The

NSC communicates to P25 Trunked Sites using IP-based point-to-point communications

providing a multi-site and multi-region call management architecture. Site-to-site, regional

communications, IP-based console interfacing, call routing, and system management are all

performed by the NSC.

Several different NSC architectures have been created to provide structured offerings to a

broad marketplace. The current NSC models are:

Pilot NSC

Standard NSC

High Availability NSC

1.3.1 Pilot NSC

The Pilot NSC shown in Figure 1-4 is the basic NSC configuration for P25 Trunked

operations. The Network Switching Server (NSS) is a fully integrated voice and data

controller deployed in a NSC. The NSS runs the data switch (MDIS) and voice switch

(VNIC) software applications.

The NSS performs the routing functions for digital trunked voice and packet data messages

through an IP backbone. It assures that voice and data messages are delivered only to those

radio sites necessary to reach the defined mobile subscribers known as peers. The NSS routes

calls to and from each voice group or mobile data user on a real-time basis and regulates

voice and data traffic on the network.

Each voice user belongs to a voice group of peers. A network administrator assigns the

members of a voice group and sets the voice group parameters including priority, hang time,

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preferred site, and response time. The NSS maintains these voice group files. The NSS routes

the IP voice traffic of one member to all the other members of a given voice group.

The Unified Administration Server (UAS) and the Regional Network Manager (RNM)

software reside on the Regional Management Server (RMS) PC. The UAS enables the System

Administrator to set up and configure a P25 radio network including the configuration of

users, their privileges, their organization, their security, and their capabilities within theregion. The RNM provides monitoring and troubleshooting of the land mobile radio region

defined by the NSS.

The optional Key Management Facility (KMF) maintains security key access codes for

regions employing data encryption features.

Figure 1-4: Example of a Pilot-NSC

1.3.2 Standard NSC

The Standard NSC shown in Figure 1-5 employs all the features of the Pilot NSC and includes

a Regional Site Manager (RSM) to manage specific call routing and site-to-si

communications requirements.

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Figure 1-5: Example of a Standard Network Switching Center (NSC)

1.3.3 High Availability NSC

The High Availability NSC (HA-NSC) shown in Figure 1-6 includes redundant (hot

standby) hardware and software applications for the Network Switching Server PC, Access

Router, and Ethernet Switch.

Figure 1-6: Example of a High Availability NSC (HA-NSC)

1.4 P25 TRUNKED NETWORK

A P25 Trunked Network consists of two or more Regions connected together and with a

NOC. The NOC provides a centralized management function for all regions within the

network.

The NOC can be located anywhere within any region, or external of all regions. The linkingpaths between Regions may be accomplished in any order, and may consist of multiple paths

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to provide Network redundancy and increased traffic handling capacity. In other words,

remote locations, such as Region 4 (see Figure 5-7) may have multiple communication paths

that improve the performance of the overall Network through redundancy and load sharing.

Figure 1-7: Example of a P25 Trunked Network with a NOC

1.4.1 NETWORK OPERATIONS CENTER

A NOC is utilized when two or more Regions are connected together. At the NOC, the

Centralized Management Server (CMS) manages the basic operations of the connected

Regions. At Regions with NOC connectivity, the RNM forwards operational info to the

Centralized Network Management (CNM) allowing the CNM to monitor regional site

activities. At the regional level, Regional Site Management activity is reported to the RSM for

historical archiving. However, when connected to a NOC, all regional RMS activity is

reported to the Centralized Site Manager (CSM) at the NOC for historical record keeping.

Optional Security Key operations are maintained by the optional Key Management Facility

(KMF). KMF operations may be maintained by a single KMF and can be located at the

regional level or at the NOC.

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Network Switching

Center

Network Switching

Center

Network Switching

Center

WAN

Centralized Network

Administration and Management

Dispatch

Consoles

Dispatch

ConsolesWAN

WAN

WAN

LAN

Dispatch

Consoles

DVU Gateway

DVU Gateway

NetworkOperating

Center

Region A

Region B

Region C

P25IP

Radio Site

Network Switching

Center

Network Switching

Center

Network Switching

Center

WAN

Centralized Network

Administration and Management

Dispatch

Consoles

Dispatch

ConsolesWAN

WAN

WAN

LAN

Dispatch

Consoles

DVU Gateway

DVU Gateway

NetworkOperating

Center

Region A

Region B

Region C

P25IP

Radio Site


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Figure 1-8: Example of a Network Operations Center (NOC)

1.5 P25 TRUNKED SITE INFRASTRUCTURE

The Station SitePro, is the heart of a MASTR III P25 Trunked station. Its primary purpose is

to provide digital signaling and transmitter control of the associated base station. The Station

SitePro interprets and directs inbound calls, processes these calls, and issues appropriate

commands about how calls are handled.

The SitePro-SiteLink(SP-SL) is a variation of the Station SitePro hardware. Its primary

function is to provide downlink communication with the NSC via the switch/router/ path. The

SP-SL in concert with the Control Channel Station SitePro, passes Control Channel data to

the NSC.

The SitePro MME uses the same hardware as the SitePro-SiteLink. However, it uses a

different software configuration that allows it to manage data call traffic.

The Site Interface cabinet also contains the SureCall P25 Test Unit (TU) system. The TU is

an optional feature of a P25 Trunked site that tests the radio channels at the P25 Trunked RF

site. It monitors the outgoing messages on the Control Channel and places test calls under thedirection of the Site Control Channel. A test call consists of sending a call request on the

Control Channel, receiving a Working Channel assignment, and checking data transmission in

both directions on the assigned Working Channel. Any failure of the Control or Working

Channels to perform as expected is reported to the Control Channel Station SitePro and/or to

the NSC. The SureCall System can also be used as a service or test radio for maintenance

personnel.

Two basic LAN communication ports exist at the base station SitePro Controller shelf, the

Management and Control LAN (MLAN), and the P25 Local Area Network (PLAN).

One or more Cisco 2950 series routers provide connectivity to all co-located site equipment.

Both the MLAN and the PLAN are Virtual LANs (VLANs) created by the routers to improveoverall throughput and data management. VLANs operate as though each VLAN is a distinct

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physical switch. The function is used at the RF Site location to provide two separate logical

networks, one for inter-site signaling and management data (MLAN) and the other for

digitized RX/TX audio and data packet handling (PLAN).

The P25 Trunked infrastructure makes use of the industry standard IP over its Ethernet

backbone to provide fast, highly reliable and fault-tolerant management and control

communications. Cisco Ethernet switches and routers provide the connectivity.WAN technology connects the 100 MB Ethernet LAN to the RF sites, dispatch consoles,

other data management locations, etc. Routers are used to create the point-to-point

connections between physical locations.

At the RF Site (see Figure 1-9), SitePro Base Station Controllers (one per channel)

communicate on a local 10 MB LAN that supports call management. Each Station SitePro,

SitePro-SiteLink (SP-SL), SitePro Mini-Mobility Exchange (MME), and the SMI-Network

Sentry communicate through a Router to the NSC via a 100 MB T1/E1 connection provided

to the router. The T1/E1 connection is routed to the Ethernet switches which divide the T1/E1

signal into two VLANs, one for data management (MLAN) and the other for voice IP packets

(PLAN), thus forming the operational appearance of two separate LAN services.

The Ethernet switches multiplex up to 24 individual Ethernet ports into a single 100BaseT I/Oport. The 100BaseT I/O ports of two or more Ethernet switches may be daisy chained together

forming a single 100BaseT port I/O portal. The daisy chain is then connected to the site

router, which provides connectivity to the T1/E1 WAN connection.

As previously discussed, the switches are programmed to provide two VLANs within the site

infrastructure. This configuration improves overall data handling by separating management

and control data from voice IP packets. Each IP-based hardware device connected to an

Ethernet switch has a unique IP address. The Ethernet switches maintain port identities and

route IP data packets to their respective hardware device.

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Figure 1-9: MASTR III-P25 Trunked RF Site Detailed System Overview

1.5.1 MASTR III P25 TRUNKED STATION OPERATION

The MASTR III P25 Trunked base station is the RF backbone for a P25 site. The station

consists of a Power Supply, Transmitter/Receiver (T/R) shelf, RF Power Amplifier and a

Station SitePro. In addition to the standard T/R shelf, the station is equipped with a Digital

Signal Processor (DSP) Module to provide the necessary encoding and decoding required for

P25 mode of operation.

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0

1.5.2 P25 Trunked Repeater Operation

In P25 Trunked repeater operation, the MASTR III base station functions much like

traditional trunked repeater stations. However, the mode of operation is 4-Level digital FM

using the industry standard APCO P25 trunked digital protocol. The P25 protocol utilizes the

digital capable features of the T/R shelf. The demodulated analog signal path from the

Receiver IF Module, as well as most analog signal paths associated with the System Module,

are not used for P25 signal processing.

Over-the-Air P25 signals are received at the RX Front End Module and passed through a band

pass filter, mixed with the local oscillator signal from the RX Synthesizer Module and the

resulting products sent to the RX IF Module. At the RX IF Module, the IF signal goes through

a series of band pass and image rejection filters, amplification and a second mixer stage

resulting in a 455 kHz second IF signal. For P25 Trunked applications, the 455 kHz IF signal

is routed to a series of amplifiers that produce a balanced 455 kHz IF output signal ( 455 kHz

IF + and 455 kHz IF -) that is sent to the DSP Module via the back plane.

At the DSP Module, the 455 kHz IF signal is processed and passed to the System Module via

the high Speed Data line EXT_HSD. The System Module acts as a toll gate, only permitting

retransmission of received signals per commands from the Station SitePro controller. The 455

kHz IF signal is also decoded and sent to the Station SitePro as serial data via the 9.6kHz-RX-

DATA-OUT line.

At the Station SitePro, the serial data signal is processed for group and unit identification andcompared to the user database stored in the Station SitePro. Validated requests are processed

and control signaling sent the System Module allowing retransmission of the received P25

signal. The System Module responds to control commands from the Station SitePro controller

and routes the P25 signal to the TX Synthesizer for retransmission.

Operational control of the TX Synthesizer Module comes from the System Module. The TX

Synthesizer Module utilizes a reference oscillator signal to lock the Phased Locked Loop

(PLL) circuitry to the frequency defined by the System Module. The resulting TX exciter

signal is modulated with the P25 intelligence, amplified and passed to the RF Power

Amplifier and ultimately to the antenna system.

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1.5.2.1 P25 Outbound Remote Control Signaling

Serial data arriving at the Station SitePro via the 9.6kHz-RX-DATA-OUT from the MASTR

III receiver is also processed into IP based packets and sent to the NSC.

At the NSC, voice packets are routed by the NSS which utilizes a system configuration

database provided by the RSM. The NSS assures that voice and data messages are delivered

only to those radio sites necessary to reach the defined mobile subscribers. The NSS routescalls to and from each voice group or mobile data user on a real-time basis and regulates

voice and data traffic on the network.

Each voice user belongs to a voice group of peers. The network administrator assigns the

members of a voice group and sets the voice group parameters including priority, hang time,

preferred site, and response time. The NSS maintains these voice group files. The NSS routes

the IP voice traffic of one member to all the other members of a given voice group.

1.5.2.2 P25 Inbound Remote Control Signaling

Voice and data packets arriving at the Station SitePro from the NSC are processed and

stripped of all IP routing information. The resulting information is passed to the DSP Modulevia the 9.6K-TX-DATA-IN line as serial data.

At the DSP Module, the serial voice data is processed into a P25 formatted signal and placed

on the high Speed Data line EXT_HSD for P25 repeater operations. The System Module

responds to control commands from the Station SitePro controller and routes the P25 signal to

the TX Synthesizer for transmission.

Frequency assignment and operational control of the TX Synthesizer Module comes from the

System Module. The TX Synthesizer Module utilizes a reference oscillator signal to lock the

Phased Locked Loop (PLL) circuitry to the frequency defined by the System Module. The

resulting TX exciter signal is modulated, amplified and passed to the RF Power Amplifier and

ultimately to the antenna system.

1.6 P25 TRUNKED SITE OPERATIONAL FEATURES

Two types of radio channel designations are used in MASTR III-P25 Trunked RF sites: The

Control Channel (CC) and Working Channels (WC). The CC is used to manage the WC

assignments of inbound and outbound repeater activity. WCs are used to repeat P25 Trunked

digital voice and data communications between radios, data systems, and console controllers.

1.6.1 RF Site Distributed Control

Distributed control of the MASTR III-P25T RF site is performed by the Station SitePro and

the SitePro-SiteLink. The Station SitePro-SiteLink combination interprets, processes, and

directs inbound and outbound calls by creating and reading IP based data packets to and fromthe NSC.

At the site, the SitePro-SiteLink handles the Group and Unit ID database and all other

parameter database transfers from the NSC. The Station SitePro-SiteLink provides digital

signaling and transmitter control of the associated base station. The SitePro-SiteLink monitors

control channel call activity, test call result messages and site alarm data, then passes the

information and data to the NSC.

1.6.2 System Call Definition

P25 Trunked supports voice and data communications modes using the APCO Project 25

Trunked protocol. Four call types are supported:

System All Call Group

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Group Emergency

Individual

Furthermore, a common infrastructure platform is used for both voice IP and data IP

communications.

1.6.3 System Call ProcessingIn a well-designed trunked system, trunked operation may be considered as providing a

"virtual" channel a communications path that always exists and is available for

communications.

The group call is the standard call on a P25 trunked radio system and may operate in one of

two different modes: P25 voice or P25 data. P25 Trunked radios can scan between the

different modes automatically.

Addressing for individual voice or data calls may be accomplished by a dispatcher or another

radio unit and can be pre-programmed into a radio.

System All Call is a pre-programmed special call in a supervisory radio and allows a

supervisor to communicate immediately to all radios within the assigned system.

1.6.4 Emergency Call Request

When a P25 Trunked system receives a group emergency call request it notifies the dispatcher

immediately and it assigns the call to a free working channel. If all working channels are

busy, the P25 Trunked system still notifies the dispatcher immediately, and the call is

assigned the next available working channel.

1.6.5 System Addressing

The signaling system has been designed to provide flexibility in partitioning the systems

users into working groups. Groupings of the radios can occur at five levels to tailor a

communications plan to fit the needs of the system: System

Agency

Fleet

Sub-fleet

Individual

P25 Trunked supports large, statewide systems with an addressing scheme that allows over

one million (1,000,000) radio IDs and 64,000 Talk Group IDs.

1.6.6 Dynamic Message/Transmission Trunking Capability

Message trunking is the process that assigns a channel in the system for the duration of the

conversation. Transmission trunking is the process that assigns a new channel every time aradio is keyed to maximize the capacity of radio channels. P25 Trunked uses transmission

trunking as the preferred mode to maximize efficiency. Message trunking is also supported if

the customer desires.

1.6.7 Transmit Busy Lock-out

The Transmit Busy Lock-out feature prevents two users from talking at the same time. When

a user keys his radio to make a call (transmits) the site validates the radio ID, assigns a

working channel, and all receiving units are prohibited from transmitting until the first user

completes their transmission.

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1.6.8 Busy Conditions

A Busy Condition is defined as when all channels at a site are in use, and another user

attempts a call. Queuing of call requests will occur. Each request is positioned in the queue

with respect to the priority of the call. Individual users and groups can be given different

priority levels. The ranking of importance for a call typically depends upon the callers level

of responsibility, the nature of his activity, and the urgency of the information beingtransmitted. If the site/system is fully loaded, any group or individual that has used the system

within the last 15 seconds is given a half-step increase in priority to ensure continuity.

Overall, under heavy traffic conditions, P25 Trunked provides intelligent traffic distribution

to facilitate non-stop critical communications.

1.6.9 Digital Operation

The P25 Trunked network combines the proven functionality and reliability of M/A-COMs

MASTR III P25 Trunked stations with state-of-the-art voice coding techniques to provide the

best possible audio quality and security in two-way radio systems.

1.6.10 Inherent Security

Since P25 is digital, it is inherently secure. Ordinary analog scanners are unable to listen to

conversations in the P25 mode. For enhanced security, a P25 radio can be encrypted with the

Data Encryption Standard (DES) orAdvanced Encryption Standard (AES) algorithms. These

types of encryption are useful for preventing unwanted interception of sensitive

communications and critical information.

1.6.11 Interoperability (Network First)

P25 Trunked Networks may incorporate Network First, the latest technology revolutionizing

the industry in Interoperability communications. As part of the Network First platform of

communications, interoperability between conventional, trunked and OpenSky systems aremade practical. Network First uses Interoperability Gateways to provide cross-platform

communications between existing trunked, conventional, and data communications systems

where otherwise not possible. They can also provide telephone interconnect capability and

access to most any source of analog audio communications.

1.7 System Management Control

The NSC promotes efficiency and effectiveness of system administrators and dispatchers by

greatly simplifying the management of trunked radio systems. Through a graphical user

interface, the System Administrator can configure the system, monitor system activity in real

time, maintain user databases, monitor alarms, and simultaneously control other types ofactivity for each subsystem. Changes in system status can be displayed visually and audibly to

alert the System Administrator. Even for very large systems, group and unit database uploads

to P25 Trunked sites and other infrastructure devices occur rapidly over a 100 MHz Ethernet

backbone.

1.7.1 Regional Network Manager (RNM)

The RNM provides for real-time monitoring and fault tracking on the P25IP network. The

RNM uses a collection of applications and administrative programs that permit the operator to

view and monitor a P25IP network from a centralized access point. At its highest level, the

RNM uses a graphically oriented interface as a visual representation of the P25 IP network. In

addition, the RNM can be accessed remotely by multiple concurrent users with UNIXworkstations or PCs. The RNM is partitionable, and multiple levels of RNM security are

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provided to ensure that an agency manager accessing the RNM does not interfere with the

operation of sections of the network outside of his or her jurisdiction.

The RNM displays fault and performance information for all managed objects in the P25IP

network, so the operator can locate trouble spots in the system and fix them quickly. It can be

set up to provide an audible alert when problems occur.

1.8 Unified Administration Server (UAS)

While the RNM is concerned with monitoring the overall performance of the network, the

UAS is concerned with configuration of subscriber units, their privileges, their organization,

their security and their capabilities.

Administrators use off-the-shelf web browsers (the UAS Clients) to access the UAS Server,

which manages the master database and downloads configuration changes to the network

switch (VNIC) and P25IP sites.

Each time a change is completed in the network database, the UAS server distributes the

changes to all network components. The database is distributed to each site and Network

Switching Center so that in the rare event that a UAS becomes inoperative, the system is able

to continue to operate with all features.

There are two types of users of interest to the UAS: subscribers (radio users) and

administrators. Subscribers are organized by agency, allowing a single administrator to

manage a collection of users and assign them, for example, the same Project 25 Talkgroup.

Three types of administrators are defined by the NAS:

Radio System Administrators The highest level of privilege available. The

UAS allows a radio system administrator to define and modify other

administrator user accounts and privileges, to define regions, and to define the

geographic scope of voice groups.

Regional Administrators The UAS allows a regional administrator to createand manage agencies, to assign pools of user IDs and talkgroups to an agency,

and to manage the range of related parameters that are available to the agency.

Agency Administrators The UAS allows an agency administrator to create

users and passwords, manage voice groups and keys, and define gateways and

consoles.

A particular person may have a combination of privileges, and may serve as the administrator

for a collection of agencies. In many typical installations, the radio system administrators and

regional administrators are the same.

1.9 Trunked Data

Data on P25 Trunked can be divided into two groups. The first type of digital information is

generated by the user mobile and portable products and includes Unit Identification,

Emergency function, as well as Status and Message handling. This data is embedded in the

P25 Trunked control channel signaling. The second data group is the digital information

generated externally by other equipment such as mobile data terminals, automatic vehicle

tracking devices, and host data computers. This type of user data passes between host

computers and MASTR III-P25T RF sites using the Ethernet infrastructure and IP based

MME Servers.

P25 Trunked totally assimilates both types of data onto a single communication system toprovide integrated voice and data trunking. The key to voice and data integration is that data

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calls are trunked in the same manner as P25 voice calls, thus bringing to data the trunking

advantages of adaptive load balancing, single radio for voice and data, fault tolerance, and

future growth opportunities.

1.10ProFile

Optional ProFile eliminates downtime commonly associated with radio personality updates.Entire radio personalities may be reprogrammed over the air for radios equipped with

ProFile. No action is required by the radio operator. ProFile Manager (a standard component

of the package) provides a user-friendly, PC-based interface for the System Administrator.

1.11Dispatch Operation

Voice dispatch operation can be provided by IP-based dispatch consoles such as the C3

Maestro IP. The C3 Maestro IP console provides intuitive, user-friendly, and powerful

dispatch operations. Consoles are connected to a network/dispatch switch to provide

conventional and trunked system dispatch features. Classic features include simulselect,

patch, emergency, group calls, and call history. The C3 Maestro provides advanced featuressuch as sending Status Messages (off duty, en route, etc.) and Request-to-Talk directly to the

dispatcher without tying up a voice channel. The console also supports other advanced

features such as paging, call director, supervisory functionality, and user-definable screens.

Traditional analog-based tone remote consoles may be incorporated into a P25 Trunked

system through the use of Interoperability Gateways. Interoperability Gateways provide the

analog and digital conversions necessary for traditional analog consoles to communicate over

an IP-based system.

The MaestroIP comes with a core package that includes computer, mouse, enhanced audio

enclosure, desktop microphone, dual headset jacks, footswitch, and two rack-mount speakers.

The mouse, as part of the core package, is the standard user interface to the console, providing

an ergonomic workstation.

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The MaestroIP can monitor up to 112 different communication modules simultaneously. This

enables the dispatcher to monitor and communicate with up to 112 P25 talkgroups, individual

radios, conventional radio channels and other dispatchers. If the dispatcher does not require

112 modules, they can be left blank or filled with individual radio names to allow rapid,

private communications with key individuals. The Maestro also stores a database of units and

groups, plus alphanumeric alias information for units and groups.The dispatcher can individually program each of the MaestroIP communication modules. This

means that a dispatcher can customize the Maestro IP to meet personal preferences or agency

standards. In addition, dispatchers in response to special situations can dynamically add new

talkgroups. Each MaestroIP consoles access menu is controlled by a console permission list.

This list defines each dispatch consoles permitted communications.

Additional standard features include:

Individual calls entered by unit ID number (LID)

Console intercom calls

Dynamic integration of talkgroups with console patch

Single button press (Instant Transmit) communication on any displayed module

Microphone, transmit key, or footswitch press for selected channel communication

Notification alert tones allows programmable tones to be associated with the

following console functions: I-Call, Request To Talk, Auxiliary input alarms, and

Un-key Beep

The MaestroIP dispatch console can be connected to an external Multiline Telephone device

provided by the customerfor telephone interconnect operations. Telephone lines can be

accessed by the dispatcher and either used for standard telephone call operations or patched

to radio entities in the radio system. The Radio/Telephone patch feature allows a dispatcher to

interconnect a telephone line at the Telephone to a talk group or to an individual radio unit.

Each console equipped with a Radio/Telephone patch can patch one telephone line at a timeto the radio system. During Radio/Telephone patch operationsnormal dispatch

communications can continue.

1.11.1 VIP Console

The VIPConsole provides powerful, yet compact dispatch capabilities when the full-featured

MaestroIP Console is not required. With four communications modules, it is perfect for

administrative monitoring of system communications. Since the console can run on a standard

PC desktop workstation, no extra equipment is needed.

The VIP Console supports the basic dispatch functions such as selected and unselected

talkgroup monitoring, selected and instant transmitting, and independent volume and mute

controls for each monitored talkgroup. Additional basic features include selective calling andcaller alias. Enhanced functionality includes emergency status monitoring and clearing and

creating Patches and Simulselects.

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The console can be equipped with optional hardware:

Footswitch (single button) Dispatch grade desk mic Dispatch grade operator headset User Interface Adapter.

Optional Software Features:

Additional Dispatch IP Interface Talkpath License Integrated Call Check recorder Call History Patch License Simulselect License M/A-COM Messaging Service - TextLink

1.12CADLink II

To interface with the customers existing CAD system, M/A-COM as an option may propose

the CADLink II. This feature makes available to the CAD system up-to-the-minute

information on unit status and field activity. CADLink II efficiently and cost-effectively

provides the messaging required to implement true digital incident handling by providing the

CAD system access to P25 unit identification, push-to-talk, and emergency indications. The

CADLink II product provides data to the CAD system; no data is received or processed from

the CAD system except for a connection message used to determine the existence of the CAD

system. Specifically, CADLink II is a set of Application Programmer Interfaces (APIs) that

allows the CAD vendor to easily develop an interface to the P25 system. This interface

provides information from the P25 system to the CAD system.

CADLink II runs on standard PC computer hardware and the Microsoft Windows operatingsystem. All external software interfaces and internal messaging systems conform to

international standards and can be upgraded/added with minimal costs and operational impact.

Important CADLink II advantages are as follows:

Simplified CAD interface to P25 - Ethernet physical host connections and TCP/IP

protocol

Transparent messaging from P25 to CAD system

Unit ID

Emergency

PTT Activity

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CAD

IntraSystem

Interface

CADLink II

Application

(workstation)

SocketInterface (APIs)

ApplicationNSC


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2.1.6 Repeater Talk-Around

All units are capable of operation in simplex, repeater talk-around mode to communicate

radio to radio when out of system repeater range or conducting a special detail intentionally

isolated from the system.

2.1.7 Group ScanThe radio monitors the control channel and responds to all group channel assignments

associated with the user-programmable scan list. This enables field users to monitor other

group activity that may affect their mission.

2.1.8 Priority Group Scan

This feature includes the Group Scan function described above with the following

enhancement. If a call occurs on the Priority group during a non-priority call, the radio

immediately transfers into the priority conversation and when concluded, returns to the

non-priority channel. This assures all calls directed to a specific user get through while

enabling cross-functional communication.

2.1.9 Transmit Lockout

This essential feature assures communication once the initiating unit is assigned a working

channel. Other users in the talk-group are precluded from interrupting (or stepping on) the

transmitting unit, assuring critical messages get through. This prevents a higher-powered

mobile unit from overriding a lower powered portable and forces discipline during stressful

situations.

2.1.10 System Failure Indicators

Display flags provide indications of system failures to enable key field personnel to diagnose

system malfunctions and provide appropriate direction to group personnel.

2.1.11 Prompt Tone

Notifies caller that communication may proceed on the assigned available working channel.

2.1.12 Late Entry

Prevents missed calls. A call late enters when the original channel assignment was missed.

2.1.13 Time-out Timer

A programmable timer will inhibit the transmitter when RF transmission exceeds a

predetermined length of time.

2.1.14 Disable/Enable

Radios can be remotely disabled, so that the radio can no longer transmit or receive. Public

safety communications are protected in the event of a stolen or lost radio. In the event that the

radio is recovered, it can then be remotely enabled, without need of reprogramming at the

shop.

2.1.15 Emergency ID and Alarm

All radios have an emergency alert button. For radios programmed with the emergency

feature, activating this button immediately alerts the other members of the units talkgroupand the dispatcher of an urgent situation and forwards the unit ID.

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2.1.16 ProScan Roaming

A wide-area system scan algorithm designed to select the system that will provide the best

voice quality for automatic roaming within a multisite network.

2.1.17 Priority System Scan

A preferred home system can be programmed into the radio to improve network efficiency

within a multisite network by keeping as many radios as possible on the primary system.

2.1.18 Data

Radios are equipped with internal modem to support data communications. All that is

required is a data cable to connect the radio to the data device.

2.1.19 OTAR & OTAP

Over-The-Air-Reprogramming of the encryption key (OTAR) and radio personality (OTAP)

reduces the amount of time and labour to rekey and/or reprogram radios.

2.1.20 Status Message & RTT

Short, pre-programmed control messages can be sent to the dispatcher with the press of a

single button.

2.1.21 TextLink

TextLink is M/A-COMs messaging application, which utilizes standard P25 packet data

transmission. It provides:

Free form text sent to and displayed on portable and mobile radios (up to 200

characters)

Two way canned messages and responses Message routing and logging

Console, Dispatch, CAD Workstation and/or 3rd Party Interface Application

support

2.1.22 Encryption

Encryption based on Digital Encryption Standard (DES) or Advanced Encryption Standard

(AES) algorithms protect sensitive communications from eavesdroppers.

2.1.23 APCO Project 25 Interoperability

P25 Digital radios are Project 25 compliant for Common Air Interface (CAI) interoperability

with other Project 25 users in the conventional talkaround mode. This makes the radio ideal

for use either as a primary P25 digital conventional radio or as a trunked radio with

talkaround interoperability.

P25 TRUNKED SYSTEM OVERVIEW

Documents