Transcript
St an d ar d by b y ETS ETSI f o r Digita igitall Mobile Ra Radio Systems
Apr-10
© Copyr Copyright ight SELEX SELEX Communications Communications.. All rights reserv reserved. ed.
Tabl ble e of co cont nte ent nts s
What is TETRA? Functionality and characteristics TETRA technology basics Technology comparison Some scenarios and applications User specific considerations The future of TETRA
Apr-10
© Copyr Copyright ight SELEX SELEX Communications Communications.. All rights reserv reserved. ed.
Tabl ble e of co cont nte ent nts s
What is TETRA? Functionality and characteristics TETRA technology basics Technology comparison Some scenarios and applications User specific considerations The future of TETRA
Apr-10
© Copyr Copyright ight SELEX SELEX Communications Communications.. All rights reserv reserved. ed.
Wha hatt is TETRA ?
Apr-10
© Copyr Copyright ight SELEX SELEX Communications Communications.. All rights reserv reserved. ed.
TETRA in short
> TETRA means TErrestrial Trunked RAdio > It is a standard specified by the ETSI during the ‘90s in response to the need of a common digital trunked standard for professional mobile radio (PMR) > TETRA has been specified by ETSI together with users and it is defined to meet the needs of the most demanding users > TETRA is an open st andard
Apr-10
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The leading technology
> TETRA is a consolidated standard and has been fully accepted by the Administrations of all European countries and in many other countries in the rest of the world. > ETSI is currently working on TETRA release 2, that will further enhance the services of TETRA and will maintain the standard future-proof.
Apr-10
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ETSI - (1/2) (European Telecommuni cations Standards Institute)
What > Produce the telecommunication standards of the future > Promote the world-wide standardization process whenever possible
Apr-10
Who > Non-profit making organization > It unites approximately 800 members from 56 countries inside and outside Europe > It represents:
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• Administrations, •
Network operators
•
Users
•
Manufacturers
•
Service providers
•
Research bodies
ETSI - (2/2) (European Telecommuni cations Standards Institute)
How
Results
> Deep analysis of customer requirements
Some references:
> Exploitation of its long experience and of the rich set of skill s of the members > Coordination with most important international standardization bodies (mainly the ITU-T and the ITU-R)
Apr-10
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GSM, DECT, TETRA, UMTS,...
TETRA MoU - (1/2)
The TETRA Memorandum of Understanding (MoU) was established in December 1994. Today it represents 100 organisations from 30 countries.
Who
Apr-10
All TETRA stakeholders: users manufacturers (the entire European PMR industry, exclusive of EADS) operators test houses telecom agencies
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TETRA MoU - (2/2)
What
Act on behalf of all interested parties in order to support TETRA adoption and evolution
Promote TETRA events and exhibitions collect users feedback support interoperability testing (IOP)
How
Results TETRA is the world-wide consolidated standard for PMR A large number of the deployed systems are multi-vendor solutions. TETRA actually is a real open standard. Apr-10
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Interoperability certification
> The Interoperability Certificate (IOP) assures that various manufacturers terminals can indistinctly operate on any TETRA network. > Tests are supervised from an independent accredited test house: initially was Teledanmark (Danish operator) now ISCTI (Italian Telecommunications Public Institute) > All functionality tested and approved are summarized in public tables
http://www.tetramou.com/facts/index.asp?pagereq=interoperability/interoperability.asp&setsub=2
Apr-10
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SCHENGEN position
> SCHENGEN Police Telecom Group (now replaced by Police Co-operation Working Group - PCWG) adopted TETRA for pan-European police communications. > ETSI confirmed that TETRA standard is compliant and supports the SCHENGEN operational and security requirements. > CEPT/ERC designated a 5 MHz spectrum in the frequency band 380÷400 MHz, for Police Forces usage of TETRA across Europe.
Apr-10
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TETRA references
(December 2005 - sou rce TETRA MoU)
> Total 788 contracts in 77 countries
Apr-10
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Functionalities and Characteristics
What are the PMR user needs? F
ul l s u pp o s r t t p u o o e f f ic r g n ie e n t a e g w t n c o n t i nd i nt e v b o r s o l r o m n eg ra t o i t ed s t u o b p m s r u i c a e o n r h u t g e m e g m o g t o w c o r k i n g o f o r l a r s w a l s s u s e r d e n t l y ; st on f ast and reli abl e communication Tru a n e e r d e p w i d e a especially under crit ical con diti ons or a n i n d under em erg enc y t e T e r as y an mi n n i c a e r e d f as t a u al m h h v ai l ab a m f o r m a w r o s h e s a bl e y i l i t y o f c r t i o n ( d e y t o v l l n v i r al l at a) ne j ob I d e a y t i m e / e o n m w o r k i ed ed t o c n r e n t ar r y o u e v e s t T ru s t o n s ons ti a c li e c u r i t y p p a d n a ls e o o a o f c o m T g ai nst h e t h d n a m u n i c a p o u d s e t e i p l s e i nt e rc t to d n t i o n s te i u e s e m p t io s t l a n n io a s s n fe d i nt er ru p impro ve pro t io n t n e r fe f i d n tasks e e n be t w n ec t io n o c r e bo rde r s ) s s o r Ea s y i n t c a c e s o i s l v a ( r s n e io o i t d s c o s t s o rgan i sa t t h n c e t
TETRA unique feature set sers that take advantage of these technologies are spread over any sectors of both public services and private companies, that eed mobile communications to support their workforce Full ile phony
Air Interface Encryption
Duplex Voice
End-to-End Encryption Status Messaging
Packet Mode
DMO
Group Priority
Mobile Security
Main features (1/2)
> Real open standard in digital mobile radio tailored for professional users > Unlimited support to point-to multipoint (group) voice and data communications, with an extensive set of enhanced ancillary services > Focus on communications between radio terminals and control room/dispatcher operators > Direct mode of operation (DMO) in order to allow communications also in fringe or out of coverage areas and at times of capacity limitations
Main features (2/2)
> Multiple security schemes and algorithms > Voice and data capabilities with 4 TDMA channels in 25 kHz channel spacing: • • •
concurr ent voice and data; full-duplex voice call using simplex radios; net data rates up to 28.8 Kbit/s.
> Standard interfaces for data terminal connections (PEI) and for TETRA networks interconnection (ISI) > Wide set of telephony and PMR supplementary services > Call Set Up Time: about 300 ms
TETRA services (1/4)
> Voice and data capabilities • 4 traffic channels in one 25 kHz radio channel • point-to-point and point-to-multi point • concurrent voice and data • full-duplex call using simplex radios • fast call set-up
> Fully digital trunked (TMO) and direct (DMO) modes of operation: • Dual watch • Repeater • Gateway
TETRA Direct Mode - Available terminals
4
4 3
3 2
Control Center
1) Basic 2) Repeater 3) Dual Watch
3
1 2
4
TETRA services (2/4)
Multiple security schemes & algorithms > Authentication: • of User / Terminal • of the Infrastructure
> Encryption: • Air Interface Encryption • End-to-End Encryption
> Security Management > Disabling of stolen radios
Security
??????xyz
Switching
Auth entication
Dispatcher
portables Handportables
Radio Base Station
END-to-END Encryption
Radio Base Station
AIR Interf. Encryption
TETRA services (3/4)
> Data rates up to 28.8 Kbit/s > Data communications • Circuit Mode Data • Status/Short Data Service (SDS) real time • Packet Data
> Data rate suitable to support applications such as: • mobile localisation • file/image transfer • slow video
TETRA services (4/4) STD. Interfaces > Air I/F > ISI > PEI > PABX (Digital/Analogue) > PSTN (Digital Analogue) > PDN (Industrial Standards)
PMR Supplementary Services Access
Priority Priority call (incl. Pre-emptive) Include call Late Entry Call authorised by Dispatcher Area selection Dynamic Group Number assignment Discreet and Ambience Listening Short Number Addressing
Network Interfaces
Internet
PDN
LAN/WAN
ISI PSTN PEI
ISDN
Virtual Private Networks (VPN)
> Possibility of sharing the same physical network among different organizations. Advantages are: •
reduced costs for infrastructure;
•
reduced cost for running the network.
Technology basics
System characteristics
OPERATIVE FREQUENCY:
Band and duplex spacing (Tx/Rx):
380÷400 410÷430 450÷470 806÷870 870÷921
Carrier spacing:
25 kHz
MHz MHz MHz MHz MHz
MODULATION: Type: Gross bite rate per carrier:
P/4-DQPSK 36 Kbit/s
(10 (10 (10 (45 (45
MHz) MHz) MHz) MHz) MHz)
Radio Access: Conventional Vs. Trunked
Conventional
Trunked
> Channels are dedicated to specific services > Uneven load distribution among channels > Waste of spectrum resources
> Channels are dynamically assigned to user requests > Traffic load distributed among channels > Optimal use of spectrum resources
Advantages of digital systems
Constant voice quality
High speed data transmission
Subscribers and network authentication
High security ciphering
Who are you ?
Digital Radio System
MICRO
FILTER
SAMPLE
COD.
COMPR. M U X
CODEC (TX)
MOD.
Transmission channel
(RF on air) SPEAKER
FILTER and PROCESSING
DECOD.
CODEC (RX)
DECOMP. M U X
DEMOD.
Bitrate on demand: TDMA and FDMA
pectrum kHz
25 Carrier 1
CH 1
12.5 Carrier 2
CH 2 To
C H
C H
C H
C H
1
2
3
4
To
Carrier 1
Time
Advantages of TDMA systems
> Bitrate on demand > Higher data rates > Simultaneous voice and data > Simplex terminals for duplex communications > One TRX to manage four traffic channels
Time Division Multiple Access (TDMA) 1 hyperframe = 60 multiframes ( = 61.2 s )
1
2
3
4
5
60
1 multiframe = 18 TDMA frames ( = 1.02 s )
1
2
3
4
5
18
control frame 1 TDMA frame = 4 timeslots ( ~ 56.67 ms )
1
2
3
1
2
4
5
3
4 509 510
1 time slot = 510 modulation bits durations ( ~ 14.167 ms ) 1 2 3
4
1 subslot = 255 modulation bits durations ( ~ 7.08 ms )
509 510
Radio channel usage: conventional analogue
1 channel in 25 kHz
1 channel in 25 kHz
CASE 1: conventional analogue systems
Radio channel usage: FDMA
1 channel in 12,5 kHz
1 channel in 12,5 kHz
1 channel 12,5 kHz
1 channel 12,5 kHz
CASE 2: FDMA analogue and digital systems
Radio channel usage: TDMA
H z k 5 2 e l i n a n n h c 1
1 c h an n e l i n 2 5 k H z
CASE 3: TETRA digital systems
Technology comparison
Why TETRA instead of proprietary PMR technologies
SI STANDARD
> Interoperability > User requirements fulfillment > Future-proof technology
STATE-OF-THE-ART STANDARD
Trunked Digital TDMA based Richest set of services EN STANDARD
Competitive prices Competitive quality
Real competition
> Currently there are: • Approximately 12 independent TETRA infrastructure manufacturers • Approximately 8 independent TETRA terminal manufacturers • A huge number of independent application developers
These figures are constantly increasing
TETRA in comparison to other PMR systems TETRA
MPT1327
TETRAPOL
SmartZone
EDACS
ETSI / EC
DTI
Forum TETRAPOL
MOTOROL A
ERICSSON
Open/Proprietary
Open
Open
Proprietary
Proprietary
Proprietary
Independent manufacturers
15÷20
roughl y 15
1
1
1
Digital/Analogue
Digital
An alo gu e
Digital
An alo gu e/ Digital
An alo gu e/ Digital
Ac cess
TDMA
FDMA
Radio c hannel bandwidth (kHz)
25
12,5
Traffic channels wit hin 25 kHz
4
2
Maxim um data tx rate (kbit/s)
28,8
7,5
9,6
Simultaneous voice and data
YES
Defin ed by
2,4
7,2 NO
Why TETRA instead of public cellular networks
GROUP COMMUNICATIONS
Unlimited extension and number of members Very powerful set of supplementary services
SECURE COMMUNICATIONS Widest
set of services:
authentication encryption radio
disabling
...
DISPATCHING ORIENTED
Focus on communications between radio terminals and control room operators Very powerful set of supplementary services
TRUNKED AND DIRECT MODE
Basic
Dual watch
Repeater
Gateway
TETRA in comparison to other public cellular networks Features
TETRA
Group/Broadcast Call Dynamic Group Number Assignment Call authorized by dispatcher Ambience and Discreet listening Authentication of the Infrastructure End-to-end encryption OTAR Physical disabling of stolen radios Direct Mode DMO Gateway/Repeater Fast Call Set-up
Packet Mode Data Circuit Mode Data
UMTS
GSM-R with li mitations
-
-
-
GSM-R
Emergency calls (preemptive) Short Data Service
GSM / GSM-R / GPRS
(real tim e) GPRS
?
How do speeds compare?
0
100
200
Indoor Terminal
2 Mb/s
UMTS Handset
384 kb/s
EDGE Handset
384 kb/s
UMTS Vehicular
144 kb/s
GPRS
115 kb/s TETRA (Rel. 1) 28.8 kb /s
300
400
2000 kb/s
Some scenarios and applications
Some data transmission applications (1/2)
Automatic terminal localization > Using GPS receivers connected to TETRA terminals the determination of the mobile position is carried out and transferred to the control room. File transfer > Using the circuit or packet mode data transfer, it is possible to transfer data from/to radio terminal (suitable equipped) to/from proprietary database even external to the TETRA network.
Some data transmission applications (2/2)
Fax > This functionality is obtained through data transfer and specialized gateways. Image transmission / Slow video > The transmission of fixed (mugshot, building maps, ...) or slowly changing images is possible using particular compression algorithms that allow the optimization of transmitted data amount and therefore channel load.
Scenario
Control room operator can simultaneously communicate with and localise the vehicles Multiple channels allow multiple separated communications at the same time Base Station g i n d n s e a t d a d a n n e g i o t i c n a i o z i d l V a n c l o
s e a t a d d n a e i c o V
Car 1 for an accident at V o i c High Road… old man with e a n d broken leg ... d a t a l s o c e n d a l i ng i z V a t o i i o c e a n n d d a t a s e n d i n g
Control Room
Scenario > Patient’s medical data sending in electronic format, directly from the ambulance while going to the hospital > Possibility of communicating with fixed telephony network or cellular network, for instance to put in touch ambulance operators with specialist doctors reachable at cellular phone
Control Room Medical data
EVENT
Ambulance
Scenario > Suspect person is identified by means of personal data in his/her documents or with electronic fingerprint. Data are sent through radios for remote d atabase research; if research is successful, complete data of suspect person (e.g. including mugshot) are sent back in real time to officers on the field.
Officer identifying suspect person
Fingerprint or Name INFO DATA BASE
Complete personal data including
Scenario
Possibility of communicating with fixed telephony telephony network or cellular network, network , for instance Integrated Command and Control centre managing an operation can put officers in touch with calling citizen in order to allow direct information exchange when needed
Control Room
Officer (e. (e.g. g. looking lookin g for the t he
Scenario
Separate communications, simultaneous and independent, among different teams operating on the same intervention and/or in the same area Co-ordinator can communicate with one team but he can be at any time alerted by another team and then change group communication
…OK team 1, …increase the flow!... report situation...
ntion please!!! Group Team Te am call ca 1 requiri ll swit ch ng to urgent communication! team 1
Communication with tea team m2
Scenario
At any given time, if the two teams need to work together, the two group communications can be merged in one thanks to groups patching
Dispatching station
…Team 2, this is team 1 calling...
m1
…OK team 1!!
Scenario > Communications are fully confidential, avoiding the risk of improper use of information by any unauthorised people (criminals, terrorists, hackers, hostile government agencies, press, …) …immediate intervention required at Blue Mountain.. P ro t ec ti on by enc ry p t i on
…OK, we are moving ..
Interception failed!!
Control Centre
Scenario When network c overage is n ot available (underground parking, tunnels, …), basic TETRA communication services are granted thanks to Direct Mode Operation Also under those conditions it is possible for Control Centre or other users under the network coverage to commu nicate with u sers outsid e of the coverage thanks to special equipment called DM-Gateway
Network
U n d e r g r o u n d
Scenario > Multiple organisations can share the network and set-up integrated communications only when needed > It is always supported the possibility to manage emergency scenarios with emergency calls, using pre-emption and granting call set-up within very short time (300ms)
…Urgent communication! Redirect the convoy…..
PROTECTED CONVOY
300 ms
Ambulance
Scenario Data transmission is supported at bitrate up to 28.8Kbps, supporting a wide range of applications including image and vi deo transmissio n
D a t a t r an s mi s si o n ntrol Room
Onboard camera
User-specific considerations
Special issues for Public Safety (1/4)
> Some specific requirements must be carefully considered when TETRA networks are going to be deployed for mission-critical use: • Reliable and Flexible network topology • BS Fallback capability • End-to-End encryption • Direct Mode Gateway • Data transmission (best bearer for service)
Special issues for Public Safety (2/4)
> Availability of radio communications for mission critical application must be granted at the largest extent > In addition to redundant elements, networks must offer the highest level of flexibility in order to streamline the network design to offer the required reliability in any customer-specific condition > Examples of these implementations are • Self healin g rings to connect Radio Base Stations • Full network links redundancy • Disaster recovery mechanisms for Switching Nodes and Network Management System
Special issues for Public Safety (3/4)
Additional mechanisms are crucial to support as far as possible the availability of communication services > Base Station Fallback operation: •
grants local communications under the BS coverage also when the Switching Node is not available (due to backbone interruption or Switching Node failure)
•
is required to provide complete set of services (individual and group voice&data transmission, security features, …) and, if possible, connection to other alternative fixed networks
> Direct Mode Gateway terminals: •
provide a valuable improvement to the possibility of communicating as they allow users to get in touch with the headquarter also when outside the
Special issues for Public Safety (4/4)
> Experiences world-wide confirm that Public Safety services efficiency is more and more dependent on the capability to manage data remotely, while moving. > One of the most valuable benefits brought by TETRA is the capability to efficiently exchange INFORMATION (e.g. localisation, database interrogation, images and video, …) between officers on the field and headquarter. > TETRA offers multiple mechanisms for data transmission and stateof-the-art performance (i.e. bitrate) in order to provide the best bearer for each application. > It is crucial hence to rely on the largest set of data transmission features provided by TETRA.
The future
TETRA Release 2: some major objectives
> New 3G applications availability obtained thanks to • Increased data transmission bandwidth
> Backward compatibility obtained thanks to • Same frequency bands as TETRA • Backward compatible air interface protocol
> Efficient interworking with 3G public networks obtained thanks to • SIM and CODEC integration with UMTS
TETRA is future proof Long Range TETRA
TETRA SIM Evolution
3G Interworking
Air IF Enhancement
High speed data
