Learn more about TETRAPOL voice services

TETRAPOL Features and Functionality
• Immediate channel access can be guaranteed to a
group of users over a wide area, even when the system
is heavily loaded or congested, such as during natural
disasters or major accidents
• Multi-site open channels (MOCH) can be used as
mutual-aid channels where different pre-defined
organisations can communicate with each other
• For instance police officers and firemen can
coordinate their actions at the scene of a fire
• MOCH can also be set-up for the exclusive use of one
organisation· They can be set up to respond in real time
to operational requirements, planned or unexpected
• A radio channel can be
temporarily dedicated to a
group of users for the
duration of their mission
(however long that may be)
• Authorised users of a
given MOCH are one or
more operational groups
defined as one of the
MOCH attributes
• Exclusive use is defined
over one or several radio
cells
• Resources are returned
to the pool of channels as
soon as the MOCH is
closed by an authorised
user
Talk group
• Messages exchanged within a group of users do not
mix with messages exchanged within another group,
therefore eliminating any risk of confusion or distraction
• People cannot overhear communications that have
nothing to do with their business
• For instance, traffic police will not monitor criminal
police communications
• A talk group is a group of
terminals and a geographic
area (ie radio cells) over
which it is valid
• A user can be member of
several talk groups
Scanning
• Users can monitor the communications of several
groups alternately
• For instance the chief of a police department may
want to monitor several different units
• Supplementary service of
the protocol
Talk group merging
• This powerful feature can be used upon request to
• Supplementary service of
allow immediate communication between teams who do the protocol
not communicate with each other under normal
circumstances.
• For instance, police and fire fighters at the scene of an
accident may need to coordinate their actions
• This greatly facilitates multi-disciplinary
communications
Dynamic group number
assignment
• When people in the field are assigned to a new
• Supplementary service of
mission, their TETRAPOL radio terminal can be
the protocol
dynamically updated over the air so that they can
participate to the communications resulting from this new
assignment
• This delivers flexibility and responsiveness regarding
operational changes, since people are not constrained to
a limited number of talkgroups pre-programmed in their
radio terminal
• For instance a fire engine reporting to district 1 may be
unexpectedly dispatched to a forest fire in district 2.
Even if its radio terminal would not recognise district 2
under normal circumstances, it may be reassigned to
district 2 over the air.
Individual call
• Two people anywhere within the coverage of a
TETRAPOL system can have a private conversation
• For instance, in a statewide TETRAPOL system, a
Multi-site open channel
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• Priorities can be used to
interrupt an on-going
private call
TETRAPOL Features and Functionality
superintendent in one county can have a private
conversation with a superintendent in another county.
And an inspector going out of his jurisdiction for an
investigation is still reachable from his normal jurisdiction
• The feature can be
enabled/disabled on a peruser basis (defined in the
user profile)
Multi-party call
• A private conversation can be extended to up to five
parties (similar to a telephone conference call)
• Location registers are
used to find the called
parties anywhere within the
system
PABX/PSTN call
(telephone interconnect)
• People in the field can receive or place telephone calls
from their TETRAPOL terminal
• This can eliminate the need to find a telephone booth
or to have an additional mobile phone when they have to
reach people who are 'external' to the TETRAPOL
system (off-duty, outside the coverage area or ineligible
to use the system ...)
• Calls can be authorised by a dispatcher prior to their
establishment for better control of this service
• For instance the PABX of an hospital can be
connected to a TETRAPOL system so that rescuers at
the scene of an accident or disaster can call physicians
or other emergency personnel on their telephone
extension
• PABX/PSTN gateway·
The feature can be
enabled/disabled on a peruser basis (defined in the
user profile)
• Calls can be
unconditionally routed to
dispatcher first
Call forwarding
• Calls can be automatically rerouted when people are
not available
• For instance a police officer leaving his car can
forward all his calls from his mobile radio to his portable
radio
• Supplementary service of
the protocol
Call transfer
• This feature is similar to telephony and can be used to • Supplementary service of
control the establishment of certain types of
the protocol
communications (for instance inbound/outbound
telephone calls) by authorised individuals (typically
dispatchers). They act as 'operators', connecting two
parties upon request from one of them.
Priority levels
• Priority levels make sure that important calls are
always treated first in case of system congestion.
• These priorities may reflect a hierarchy (among people
or departments) but also an operational situation
requiring special treatment of the call, whatever the
hierarchy of the person. This second aspect is important
in situations such as a superintendent making a routine
call vs a traffic police officer making an urgent call to
report an accident. Priority should be given to the traffic
police officer although individually ranked in the system
below the superintendent. TETRAPOL makes this kind
of discrimination possible
• Supplementary service of
the protocol
• Combination of priorities:
• User priority
• Talkgroup priority
• Recent-user priority
• Preemption priority
• Retention priority
• User-selectable call
priority
• ...
Pre-emptive emergency call
• In the most critical situations, when life is at risk, users
can always call for help. Even if the TETRAPOL system
is already fully used, the message gets through at once,
cutting off ongoing communications if necessary
• Colleagues or dispatchers can immediately be notified
of the situation
• Frame stealing is used
on a traffic channel to force
transmitter interruption and
to re-allocate the resource
to an emergency call
• Various parameters are
available to adapt to
different operational
requirements for handling
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TETRAPOL Features and Functionality
an emergency call (people
receiving the call, singlecell or multi-cell call, ...)
Ambient listening
• Transmission can be remotely and discreetly activated • Supplementary service of
on a TETRAPOL radio terminal. This means for instance the protocol
that a dispatcher who gets no answer or no news from a
radio terminal can monitor what is going on (shots,
voices, etc...). This is an important feature when people
are unable to use their radio, such as when they are
under attack, held hostage or injured
Direct mode
(ie 'simplex' channels)
emergency call
• Emergency calls can be placed even in areas where
coverage from the system is not planned for (for instance
in remote areas)
• A person in a critical situation can always get help
from colleagues within radio coverage, even from those
who were not on the same direct mode channel (people
no longer have to switch from channel to channel before
they can find somebody)
• For instance, when several teams are working
separately at the same place, this powerful feature will
warn everybody if something goes wrong
Direct mode with dual watch
• Users who have switched to direct mode channels are • Dual watch still monitors
not isolated from the radio network and from their
the control channel to
dispatchers as long as they are within the coverage of
detect incoming calls
the TETRAPOL system.
Late entry
• A user does not miss ongoing communications, even if • Supplementary service of
he arrives late in the TETRAPOL system (when
the protocol
emerging from an underground car park or other area
without coverage) or if he was already engaged on a
different call
Talking party identification
• Radio ID can be sent on each Push-To-Talk activation • Supplementary service of
so that a transmitting terminal can be immediately
the protocol
identified. This helps dispatchers avoid confusion and
discourages misuse of the system
End-to-end encryption
• Communications are protected from commercial and
more sophisticated scanners
• Communications are encrypted within the whole
system: there is no weak section where communications
are transported in clear mode (for instance between a
switch and remote dispatcher consoles, or between
repeater sites and switches). This provides the highest
level of protection against eavesdropping
• Repeater sites do not need extra protection since they
do not need to include encryption modules
• Encryption algorithms
may comply with
TETRAPOL specifications
or specific algorithms can
be used
Secured over-the-air key
distribution
• Key loaders are no longer used to change encryption
keys in the radio terminals
• This eliminates many important issues associated with
key loaders, such as errors when downloading new
keys, missed terminals, loss of programming devices
used in the field ...
• Keys can be renewed and downloaded in the
terminals more often (typically daily) whatever the size of
the terminal fleet
• Key management center
• New encryption keys are
automatically distributed
periodically to the terminals.
• Keys are distributed overthe-air in an encrypted
format and following
authentication procedures
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• The direct mode
emergency frame is
transmitted on a preprogrammed channel
monitored by all radio
terminals
TETRAPOL Features and Functionality
• It is not necessary to bring terminals back to reprogam
the encryption keys, therefore saving time and
eliminating downtime and disruption for users
User-friendly encryption
mechanisms
• Users do not have to remember key selections,
whether for voice or for data communications, because
this is done automatically by the system. They can fully
concentrate on the operational aspects of their missions
and do not have to worry about the 'technical' ones
• Encryption is maintained and automatic while the
terminal roams through a nationwide system.
• For instance, with a nationwide TETRAPOL system,
narcotics officers can use end-to-end encrypted
communications anywhere and at any time without
having to do any manual action on their radio terminal
• Encryption can be
activated in direct mode but
it is a voluntary action from
the users
Mutual authentication
• A TETRAPOL system is protected against
sophisticated smart attacks, such as the intrusion of
unauthorised terminals by 'masquerading' or the use of a
'decoy' infrastructure
• Mutual authentication
between system
components
• Challenge response
mechanisms
Protection against lost or stolen • Lost or stolen TETRAPOL terminals can be
terminals
neutralised over the air, either on a temporary basis (i.e.
the terminal can return to normal operation after it
receives the right command from the system) or on a
permanent basis (i.e. requiring subsequent maintenance
of the terminal)
• When terminals are lent to an organisation hosted on
a TETRAPOL system for the duration of a special event,
they can be disabled as soon as the event is over, even
before they are returned. This guarantees a strict control
of their use
• If the radio terminal was
switched off, it is disabled
as soon as it is switched on
(at the next registration
transaction)
• Different organisations can share capital expenditure
and running costs while getting a better common system
• Each organisation maintains full operational and
tactical independence and privacy
• Communications between organisations are possible
when required and if authorised at the system level
• Higher operational efficiency and responsiveness
during mutual-aid operations
• A TETRAPOL system can reflect the administrative
structure of each organisation in terms of its hierarchy,
functions and jurisdiction
• Each organisation can have a guaranteed quota of
resources, even when the system is heavily loaded, such
as following a major incident
• Technical, tactical and
operational management
functions are addressed
separately
• Tactical and operational
functions are managed by
each organisation, technical
management functions are
the responsibility of the
system 'operator'
Virtual private networking
Common platform for voice and • The same infrastructure and radio terminals are used
data communications
for voice and data communications
• This is a simple solution for users since they do not
have to switch between voice and data channels or
terminals.
• Vehicles and radio sites are not overloaded with
equipment
• Costs can be saved on
• spare parts
• training of maintenance personnel
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• Integrated voice and data
solution
TETRAPOL Features and Functionality
• system supervision, installation and maintenance
• site equipment and radio terminals
Mobile data
• Databases can be accessed and updated in real time
from the field, eliminating discrepancies or interaction
with a third-party.
• People are relieved from paperwork in the field since
they can immedialtely update databases, send reports,
etc
• Voices messages are prone to misunderstandings,
especially in a noisy environment. Data messages are
not, so people always get the right address or the right
name
• A data transmission can be much richer than a voice
communication, including maps, text, pictures, etc.
People in the field can get more information about their
assignments, which can increase safety and
effectiveness
• Voice traffic can be reduced, in turn reducing the
background noise for radio operators in cars and control
rooms, enabling them to concentrate on important radio
traffic
• Information is distributed more selectively. Only people
who read the message know it, whereas a voice
message can be overheard by more people, perhaps
even those who should not hear it (eg a suspect may
hear communications about his criminal record while in a
police car)
• Information can be stored if the addressee is not
available, whereas a voice message would have to be
repeated later
• Integrated data services·
electronic mail
• status· short messages
(SMS)
• IP
• Standard data interfaces
• APIs (Application
Programming Interfaces)
are available for the
development of specific
data applications
Connection to other
telecommunication networks
• A TETRAPOL system can extend an existing
information system
• Past investments can be preserved
• Field personnel can get access to information systems
they are already familiar with
• People in the field get a real 'mobile office'
• They do not have to return to their office to complete
their admin jobs (job tickets, database queries, e-mails,
reports, ...)
• TETRAPOL
specifications include
various gateways to other
networks (TETRAPOL
networks, other PMR
networks, Packet Data
Networks, PTSN/PABX
networks, ...)
Similar audio quality in clear
and encrypted modes
• Since encryption does not degrade the audio quality,
users can activate it whenever required to protecting
themselves and/or their missions
• Encrypted voice is always crisp and clear. It does not
impair efficiency since repetitions of messages are not
necessary
• Excellent speaker recognition helps team members
engaged in a critical operation to communicate quickly
with each other, without having necessarily to identify
themselves each time they talk
• The voice is already
transmitted in a binary
format in clear mode. Since
the digital encryption is
applied to already-digital
information, it is not
noticeable to the user
High-performing vocoder in
noisy environments
• Noisy backgrounds (shouting crowds, fire engines,
sirens, ...) are suppressed
• This eliminates the audio 'discomfort' created by
interfering background noises
• Messages are received crisp and clear all the time,
• RP-CELP vocoder
• 14 Mips
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TETRAPOL Features and Functionality
avoiding repetitions or misunderstandings
• This means greater efficiency and less stress for radio
operators
Flexibility / modularity
• TETRAPOL systems can adapt to / grow with
organisations, serving local to nationwide users
• Star, daisy-chain, and meshed topologies are possible
• Local systems can be connected later on into a
seamless system
• TETRAPOL
specifications leave open
the size and the topology of
the systems developped by
the manufacturers
Wider radio coverage than
competing solutions
• Fewer repeater sites are necessary to cover a given
area
• Large radio cells suit rural areas where dense cellular
architectures are not an economically viable solution
• Time can be saved on system engineering, installation
and maintenance activities: wide-area systems can be
set-up more quickly
• Costs can be saved on
• system engineering, installation and maintenance
• leased lines
• site rentals
• civil work
• site equipment
• Finding repeater sites is not an issue when going from
analog to digital. System operators can reuse their
existing analog sites without having to add new ones and
can even reduce the number of sites in some cases
• Oustanding sensitivity (121 dBm) thanks to
• narrow channels (12.5
kHz)
• robust modulation
(GMSK)
• sophisticated channel
coding (FEC) including
block coding, cyclic coding
and interleaving· coherent
demodulation
• non-transparent base
stations
• non-transparent packet
data transmissions
• Sensitivity can be even
further enhanced with
antenna diversity
techniques
• RF power amplifiers with
high efficiency (Class C)
Same radio coverage for voice
and data communications,
whether clear or encrypted
• Users do not have to worry about getting a good signal
from a repeater before transmitting data or encrypted
voice. They get an efficient and reliable communication
tool whenever required
• Different codings for
voice and data, with a much
stronger protection for data
• Non-transparent packet
data transmissions
• Residual error rate (ie
quality) is the prime
concern in a TETRAPOL
system, not raw data rate
Data transmissions do not
require additional sites
• Radio engineering is identical for voice and data
communications, whether clear or encrypted
• Engineering is easier, quicker and cheaper
• The later introduction of data services or encryption in
a voice system does not require re-engineering of the
system (from a coverage point of view). Systems can be
upgraded smoothly
• Different codings for
voice and data, with a much
stronger protection for data
• Non-transparent packet
data transmissions
• Residual error rate (ie
quality) is the prime
concern in a TETRAPOL
system, not raw data rate
Spectrum-efficient solution
• Users get more traffic capacity within the same radio
spectrum. This may eliminate channel congestion
problems
• For example, a TETRAPOL solution can more than
triple the traffic capacity that would be available with a 25
kHz analog wide-area system
• 12-cell reuse pattern
thanks to an Carrier-toInterference ratio (C/I) of 15
dB
• Simulcast capabilities·
Trunking techniques
• 12.5 kHz minimum
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TETRAPOL Features and Functionality
requirement in all
configurations (direct mode,
repeated direct mode, trunk
mode)
Trunking (automatic and
dynamic allocation of system
resources)
• People do not have to think in terms of radio channels
anymore. Operational entities are the only things they
have to be familiar with for their communications (like
'traffic police', 'criminal police', 'fire department', 'chief'
etc)
• They get a more user-friendly tool
• They do not have to select radio channels anymore,
whether for voice or for data transmissions, clear or
encrypted
• They do not run the risk of selecting or staying on the
wrong channel
• They do not notice the failure of a radio channel, since
another one would be automatically allocated by the
system
• Trunking of resources is
part of the system protocol
(message trunking, quasitransmission trunking)
Simulcast capabilities
• Systems can be rolled out even when few channels
are available, as in most big cities
• With a simulcast configuration, moving from one radio
cell to another is totally imperceptible for all the people
involved in the communication
• For instance, with a simulcast TETRAPOL system
installed along a highway, highway patrols involved in a
common operation over tens of kilometres will enjoy
uninterrupted communications, although they may be
quickly crossing radio cells
• A radio cell can be extended to difficult areas (for
instance, behind a group of buildings) where there is no
radio coverage otherwise
• The limited impact of
inter-symbol interference in
a TETRAPOL system
eases the engineering
issues of simulcast
configurations
Cellular radio coverage
• Local and individual communications can be better
distributed among / confined within radio cells
• The overall system capacity is increased
• Traffic within one jurisdiction does not disturb traffic
within an adjacent one
• Cell sizes can be adapted to the type of coverage
(mobile or portable)
• Better grade of service
• TETRAPOL is based on
a cellular architecture
concept
• 12-cell reuse pattern with
C/I = 15 dB
• Mixing pure cellular
coverage and simulcast is
possible
• Late-entry service
• Controls channels
broadcast information about
neighbouring cells
Seamless roaming
• Users do not have to worry about channel selection or
repeater coverage while roaming within the system
• A dispatcher is always able to reach people in the right
cells, even when they leave their jurisdiction
• Cellular concept with
mobility management
• Home Location
Registers, Visitor Location
Registers
• Registration mechanisms
with attach/detach
• Cell Selection /
Reselection mechanisms
• Late-entry service
12.5 kHz solution
• TETRAPOL systems can easily fit in current PMR
• GMSK modulation with
20.2.2009
TETRAPOL Features and Functionality
frequency plans and rasters without prior spectrum
BT = 0,25
refarming, which is a complex and lengthy process
• Analog channels can be easily converted into digital
channels. System conversion can be planned on a perchannel basis and an analog repeater can be simply
swapped for a digital one
• Simple system configurations (Direct Mode, Repeated
Direct Mode) do not require more than 12.5 kHz
GMSK modulation
• Even clear communications cannot be monitored with
commercial scanners (digital radio transmission)
• Easy implementation of high-output RF power
amplifiers increases possible radio coverage
• GMSK with BT=0,25·
Constant envelop
• Class-C RF power
amplifier
• Power in adjacent 12.5
kHz channel: - 60 dBc (-70
dBc in an adjacent 25 kHz
channel)
FDMA on narrow channels
• Large cells are available for rural areas, reducing the
number of repeater sites needed to cover a given area
• Simulcast configurations are possible
• Saving radio channels when required
• Allowing fully-transparent hand-overs
• Good intrinsic protection again the loss of a radio
channel (shutdown, jamming, failure, ...) at a repeater
site
• It only slightly reduces the overall system capacity
(loss of one communication resource only) compared to
a TDMA system where several communication resources
are lost when a radio channel is inoperative (eg four with
TETRA)
• Direct mode (ie 'walky-talky' mode) is higly-reliable
• The same radio terminals can be used in any
environment (urban areas, hilly terrains, simulcast
systems, ...)
• Limited impact of intersymbol interferences
• No equalisation required
in the TETRAPOL radio
receivers
• Receiver noise limited
due to the use of narrow
channels
• No tricky multi-slot
synchronisation constraints
Peaceful coexistence with other • Radio spectrum can be used at best (no need to leave
PMR systems
radio channels unused between existing ETS 300-113
systems and new TETRAPOL systems).. This means no
wasted traffic capacity
• During a transition period, a user can run its analog
system and its new TETRAPOL system in parallel on the
same repeater sites
• GMSK modulation with
BT = 0,25· Constant
envelop
• Power in adjacent 12.5
kHz channel: - 60 dBc (-70
dBc in an adjacent 25 kHz
channel)
• Compliance with
European ETSI standard
ETS 300 113
20.2.2009