TETRA DEC02

NOKIA TELECOMMUNICATIONS

TETRA The pan-European trunking standard

TErrestrial Trunked RAdio


Τι είναι το TETRA?

• Νέο Ευρωπαϊκό Πρότυπο για ραδιοεπικοινωνίες • Καθορίστηκε από το ETSI (1995, 22 Χώρες)• Πλήρως Ψηφιακό Επαγγελματικό Σύστημα Κινητών Επικοινωνιών

• Παρέχει υψηλό βαθμό ασφάλειας και αξιοπιστίας • Υποστηρίζεται από πολλούς κατασκευαστές• Θα χρησιμοποιηθεί από τις περισσότερες Ευρωπαϊκές χώρες


Τι είναι το ETSI?

• Ευρωπαϊκό Ινστιτούτο Τηλεπικοινωνιακών προτύπων

• Παράγει Τηλεπικοινωνιακά πρότυπα για τις χώρες της Ενωμένης Ευρώπης και τις λοιπές δυτικοευρωπαϊκές χώρες

• Τα πρότυπα του ETSI είναι προαιρετικά για τις χώρες μέλη


Οι Διεπαφές του TETRA

• AIR IF: Ασύρματη διεπαφή• TEI:Διεπαφή Τερματικών συσκευών (ανάπτυξη εφαρμογών data)

• ISI: Διασύνδεση δικτύων TETRA • DMO: Απ’ευθείας σύνδεση τερματικών

AIR IF

ISI

TEIDMO

Open interfaces:

BSControllerGateway


TETRA Connectivity

TEIOKC

SERV 69

F BABC

STOCKHOLMTRAFIK 2

ISI

LAN/WAN

PSTN

PABX

Command &ControlSystems

PublicDataNetwork

Internet

ISDN

TrunkingNetworks

ConventionalPMR Networks

2B+D30B+D

ConventionalBase Stations

Customer Care & Billing Systems


TETRA Voice + Data Services

Tetra Network

MobileTermination

TerminalEquipment

NetworkTermination

TerminalEquipment

TerminalInterface

TerminalInterface

Man-machineInterface

Man-machineInterface

TELESERVICES

BEARER SERVICES


Διεπαφές TETRA

1.System air interface2.Direct mode air interface3.Man-machine interface4.Radio data peripheral

interface5.Local dispatcher6.Gateway to external

network7.Remote line connected

terminal8.Inter system interface9.Network management

interface

Local Dispatcher

5

6

8 Inf.

7 Remote Line Dispatcher

NetworkManager

9Inter System

Interface

Base Statio

n

Gateway

1

24

SystemInfrastructure

Base Statio

n

Base Statio

n

ISDNPSTN/ISDNPABX/PDN

3

InfrastructureControll

er


Νέα χαρακτηριστικά του TETRA• Πλήρης αμφίδρομη λειτουργία • Ταυτόχρονη μετάδοση φωνής και

δεδομένων με μια σύνδεση• Κρυπτογράφηση δύο επιπέδων:

– Βασικού επιπέδου στην (ασύρματη διεπαφή);

– Κρυπτογράφιση απ’άκρη σ’άκρη (end-to-end encryption) ειδικά για χρήστες του τομέα Δημόσιας Ασφάλειας

• Λειτουργία Ανοικτού Διαύλου (open channel mode)

• Λειτουργία Παρακολούθησης (dual-watch mode)• Υψηλός ρυθμός μετάδοσης δεδομένων


Βασικές Υπηρεσίες TETRA

Φωνητικές Υπηρεσίες: Συνήθης κλήση Ομαδική κλήση Ομαδική κλήση με επιβεβαίωση Κλήση τύπου Broadcast Συνήθης ή

κρυπτογραφημένη συνδιάλεξη

Υπηρεσίες Δεδομένων:Χωρίς προστασία μέχρι 28,8 kBits/s

Με προστασία μέχρι 19,2 kBits/s Με μεταγωγή Κυκλώματος (Circuit Switched) Με μεταγωγή Πακέτου (Packet Switched)


TETRA Voice + Data Services• Bearer services:

• Circuit mode data 7.2/14.4/21.6/28.8 kbit/s• Circuit mode protected data 4.8/9.6/14.4/19.2 kbit/s

• Circuit mode heavily protected data 2.4/4.8/7.2/9.6 kbit/s

• Connection oriented packet data• Connectionless packet data

• Teleservices:• Speech for individual call, group call, acknowledged group call, broadcast call

• Status and short data messages


Essential Supplementary ServicesCall Authorised by Dispatcher

Dispatcher verifies call request before allowing call to proceed.

Area Selection Defined areas of operation for users. Can be redefined on a call by call basis.

Access Priority Radio Unit uplink access prioritisation during congested periods.

Priority Call Access to network resources can be prioritised

Late Entry Latecomers may join a call in progress.

Pre-emptive Priority Call

This call has the highest uplink priority and highest priority access to network resources. If system is busy the lowest priority communication will be dropped to allow this call to continue. Equivalent to an "Emergency Call" in PMR terms.

Discrete Listening Authorised RU may monitor a communication without being identified.

Ambience Listening Dispatcher may turn on the transmitter of a RU without any indication being provided on RU. Can be used in hijack situations to listen what is happening in the car.

Dynamic Group Number Assignment

Allows the dispatcher to program new group numbers into the RUs over the air. Can also be used to group participants in an ongoing call.


Optional Supplementary ServicesCalling Line Identification Present

Displays the unit ID of calling partyConnected Line

Identification PresentDisplays the unit ID of the called party

Calling/Connected Line Identification Restriction

Either party may prevent display of unit ID

Call Report Displays calling party ID on a busy RU

Talking Party Identification

RU automatically identifies itself whilst in a group call

Call Forward Unconditional

Allows an RU to forward all calls to another RUCall Forward on

Subscriber BusyAllows an RU to forward calls if RU busyCall Forward on

Subscriber Not ReachableAllows an RU to forward calls when out of service or switched offCall Forward on No Reply Allows an RU to forward all unanswered callsList Search Call Incoming call will sequence through a user defined list until call is answeredShort Number Addressing Short number dialling

Call Waiting Notification of an incoming call to a busy RUCall Hold Allows user to interrupt existing call and re-establish when requiredCall Completion Busy

SubscriberIncoming call will wait until subscriber is free before calling backCall Completion No Reply Incoming call will wait until subscriber has made a call before calling backTransfer of Control Initiator of a group call can transfer ownership to another partyInclude Call Ability to include an RU in an existing callAdvice of charge Call charge information at start, during or end of call

Call Barring Ability to bar a call from/to a user defined listCall Retention Ability to prevent call being pre-empted


Χρήστες συστημάτων TETRA

Επιχειρήσεις κοινής Ωφέλειας

Υπουργείακαι Αστυνομία

Αγροτικές περιοχές

Ιδιωτικές Εταιρείες με μεγάλο στόλο οχημάτων


Τομέας Δημόσιας Υγείας και Ασφάλειας

• Αστυνομία (Τελωνεία,, Τροχαία κ.λ.π.)• Στρατός• Πυροσβεστική και οργανισμοί Διάσωσης• Πρώτες Βοήθειες και Ιατρικές υπηρεσίες έκτακτης

ανάγκης


Τυπικό δίκτυο TETRA για τον Τομέα Δημόσιας Ασφάλειας

OTHER TETRANETW O RK

BSCPSTN

ISDN

PABX

PDN

BTS

BSC/BCF

LAPD

BSC/BCF

BSC/BCF

PABX

BTS

BTSISI

CO NTRO LRO O M

BTS

LTPC

PSTN

ISDN

PABX

PDN

BTS BTS BTSBTS BTSBTSBTS

HRS

10A

+- 12V

VO LUM EM IN . M AX.

TLC 2 kmLO CAL TLC 200 M

1 2 3 4 5

6 7 8 9 0

CA N

FN Z

V OL+

VO L-

SEL

RS 232

MICRO

O C TX

G F 10 0

PRE SENZA 12VIN DISCARICAIN CARIC AIN LIM ITAZ.

FRS

HRSVRS HRS

10A

+- 12V

VO LUM EM IN. M AX.

TLC 2 kmLO C AL TLC 200 M

1 2 3 4 5

6 7 8 9 0

CA N

FN Z

V OL+

V OL-

SEL

RS 232

M ICRO

OC TX

G F 10 0

PRE SENZA 12VIN DISCARICAIN CARICAIN LIM ITAZ.

FRS

VRS

HRS

HRS

NETW O RKM ANAG EM ENT

10A

+- 12V

VO LUM EM IN. M AX.

TLC 2 kmLO CAL TLC 200 M

1 2 3 4 5

6 7 8 9 0

C A N

FN Z

V OL+

V OL -

S EL

RS 232

MICRO

OC TX

G F 100

PRE SENZA 12VIN DISCARICAIN CARIC AIN LIM ITAZ.

FRS

LAPD

LS


Υπηρεσίες TETRA για τον Τομέα Δημόσιας Ασφάλειας

Service

4 Dispatcher4 Clear and ciphered

voice4 PABX/PSTN manual access4 PABX/PSTN automatic

access4 Image transmission4 Host database access4 Radio Local Network

(RLN)4 Computer Aided

Despatching+ G.P.S.dead Reckoning

Digital Map+ G.P.S.dead Reckoning

+ G.P.S.dead Reckoning

TETRA Network

T

Automatic

TManua

l

HOST

Command &Control Centre

+R.L.N.

+

+

Dualwatch

PABXPSTN

PABXPSTN


Resources management

and positioning

EVENT DECISION INTERVENTION

TETRA NETWORK

DATA BANKS


ΕΠΙΧΕΙΡΗΣΕΙΣ ΚΟΙΝΗΣ ΩΦΕΛΕΙΑΣ

• Δίκτυα Παροχή Ενέργειας (Αέριο, Πετρέλαιο, Ηλεκτρική Ενέργεια κ.ά.)

• Μεταφορές (Τραίνα, Στόλοι οχημάτων κ.ά.)• …


Εφαρμογές πελατών• Operational Services: Voice

– Radio Communications with remote areas (extraction wells, booster stations, etc) and Mobile Operators (maintenance and emergency squads, etc).

– Telephone Communications between peripheral offices, headquarters, and PSTN.

• Operational Services: Data– Efficient Informatic Networks for transmission of data regarding Company’s activities (ex: Energy Production, Treatment Processes, etc.)

– Administration and Management.– Computer applications for production forecast and accounting.

– On - line tasking and job control.


• Operational Services: Remote Control– Radio Remote Control of Gas Oil fields, Booster Stations, Oil Treatment Plants, Power Substations, Railways Stations, etc.

– Telesurveillance for Remote Sites to prevent fires, intrusions and terrorist attacks.

– Remote metering.

• Commercial Services: (Service Providing)– Voice: - Mobile Communications (Radio Telephony)

- Fixed Communications (PABX Network) – Data: - Electronic Payment

- Others (fax facilities ...)

Εφαρμογές (συνέχεια)


Υπηρεσίες Κέντρου Ελέγχου υποστηριζόμενες από το TETRA

On-boardsub-system

TETRA NETWORK(voice/data)

TYPE OF ALARM

EVENTRADIO

OPERATORSCONTROL

CENTRE

INTERVENTIONMANAGEMENT

OPERATIONMANAGEMENT ANDSUPERVISION

BSC/BCF

Voice

Data

Satellite Antenna

GPS SATELLITE

EXTERNALDATA BANK

GPSSatellite Antenna

Data acquisition (Gateway towards external Data Banks).

Vehicles localisation

Data transfer toward operative locations

Communications between centre and

periphery.

models and statistics


Σύστημα TETRA : Τηλεεπιτήρηση

• Remote Video Control of critical areas.

• Anti-intrusion Systems.

• Fire-alarm Systems.

• Access Control.


TETRA System:Telesurveillance example CCTV

networkM M M M

D

Videocameras

Local Contro

l

CSM

CENTER

Radio TETRA Network

M = Optical modulatorD = Optical demodulatorMI = Management interfaceCSM = Central system management

Remote Area

T/R T/R


Μονοκυψελωτό σύστημα TETRA


Πολυκυψελωτό σύστημα TETRA

SystemControl

lerSystem

Controller


Ζώνες Συχνοτήτων στην Ευρώπη

• MoU on common frequency allocation has been signed by most European countries

• Non-NATO countries may allocate military band for civil use (plans for commercial use atleast in Austria and Finland)

• Plans for civil TETRA networks in 410-430 MHz band in many European countries (already 2 licences in UK)

• Other planned frequencies: 450-470 and 870-876 / 915-921 MHz

NATO military use

380

390 400383

385

395

393


Τεχνικά Χαρακτηριστικά TETRA

Channel Spacing: 25 kHzModulation: PI/4 DQPSKChannel Data Rate: 36 kBits/sSpeech Code Rate: appr. 4,8 kBits/sAccess Method: FDMA/TDMA, 4 TimeslotsUser Data Rate: 7,2 kBits/s per TimeslotVariable Data Rate: 2,4 up to 28,8 kBits/s


TDMA Timeslot Channels

"Downlink"Frequency

1 2 3 4 1 2 3 4 1 2 3 4

1 2 3 4 1 2 3 4 1 2 3 4

Time

"Uplink"Frequency

• Channel = Timeslot sequence (Frequency)

• 4 Channels per RF carrier occupying 25 kHz

• Channels may be used for control or trafficBase

Station DownlinkUplink


TETRA TDMA

• speech calls use one channel• data calls can use up to 4 channels (multi-slot data)


Τεχνικά χαρακτηριστικά TETRA

Το προσφερόμενο φάσμα χωρίζεται με διαίρεση συχνότητας (FDMA) σε κανάλια με εύρος ζώνης 25KHz το κάθε ένα

FDMATDMA

Κάθε χρήστης έχει στη διάθεση του συγκεκριμένη χρονοθυρίδα που είναι χρονικά μετατοπισμένη κατά 2 θυρίδες στην κατερχόμενη ζεύξη

Κάθε κανάλι χωρίζεται με διαίρεση χρόνου σε 4 χρονοθυρίδες

f1

fn

f3

f2

ΠΑΡΆΜΕΤΡΟΙ ΤΙΜΕΣΣυχνότητα λειτουργίας 400 – 900 MHzΕύρος ζώνης κάθε καναλιού 25 KHzΑπόσταση ασφαλείας 10 MHZΜέθοδος προσπέλασης TDMAΑριθμός χρονοθυρίδων 4Διαμόρφωση PI/4 DQPSKΡυθμός RF καναλιού 36Kbit/sΡυθμός δεδομένων ανά χρονοθυρίδα 7.2 Kbit/sΑποδοτικότητα 80 κανάλια ανά MHzΕπίπεδα ισχύος (σταθμού βάσης) 0.6 – 40 W (10 επίπεδα)Επίπεδα ισχύος (κινητού σταθμού) 1, 3 , 10, 30 WΕυαισθησία δέκτη -115 dBm


TETRA Οικονομική Τεχνολογία

Trunking technology supports controlled

use of shared networksFour-channel TDMA gives

excellent spectrum economy - 4 channels in

one 25 kHz carrier

TDMA makes cost-effective base

stations


TETRA Αξιόπιστη τεχνολογία

• Effective priority schemes ensure delivery of important messages

• Direct mode communications, mobile repeater and gateway functions give added reliability and availability

REPEATERDMO

GATEWAY


Speech Codec & TDMA Frame

A/DACELPspeechcoding

4.56 kbit/s

Channelcoding

7.2 kbit/sSpeech in

4:1 TDMA Frame

MUX

Gross Bit Rate 36 kbit/s

D/AACELPspeechdecoding

4.56 kbit/s

Channeldecoding7.2 kbit/s

Speech out

DEMUX


Vocoder Principle

Analog Speech60 ms Framelength

Transformation usinga Codebook

Samples

DA Conversion of Speech

Radio Transmisson

01100011010111101......1001000......0110011......111 . . .0101......001

10110100010.....1001101011

01100011010111101......1001000......0110011......111 . . .0101......001

10110100010.....1001101011


Speech Compression

TS 2 TS 3TS 3TS 2"Inbound" Frequency

Speech frame 1 Speech frame 2

• 60 ms of real speech are coded and compressed for transmission in 14 ms

• Allows four voice channels to be time multiplexed on carrier frequency

Transmitting RadioMicro

TS 4 TS 1 TS 4 TS 1


Speech Expansion

"Outbound" Frequency

14 ms of digitally coded speech is decoded and expanded backto the original 60 ms analog voice signal

Receiving Radio Laudspeaker

TS 2 TS 3 TS 3TS 2

Speech frame 1 Speech frame 2

TS 4TS 1 TS 4 TS 1


TDMA Frame Structure

• Slow Associated Control CHannel (SACCH).• Gross bit rate 17 x 510 bits / 1.02 s = 8.5 kbits/s/channel

Hyperframe (61.2s)

Multiframe (1.02s)

TDMA frame (56.67ms)

1 2 3 4 17 18

1 2 3 4

508 509 5101 2 3 4 5

1 2 3 4 605

controlframe

Time slot (14.167ms) = 510 modulating bits


Essential Supplementary Services for Public Safety

Application• Call Authorised by Dispatcher CAD• Area Selection AS• Access Priority AP• Priority Call PC• Late Entry LE• Pre-emptive Priority Call PPC• Discreet Listening DL• Ambience Listening AL• Dynamic Group Number Assignment DGNA


Existing TETRA Public Safety Plans

• UK Home Office: 100 000 users from police & fire

• Germany: 400 000 users from police & rescue

• Netherlands Home Office: 50 000 users from police, fire & ambulance

• Belgian Home Office: 40 000 users from police, fire & ambulance

• Finland: 50 000 users from police, fire & rescue, border guard + some other offices

• Austria, Switzerland, Spain, Portugal, Italy, Greece, Sweden, Norway, Hungary, Romania, Estonia, ...


TETRA vs. Cellular Systems

• Different use requires different tools• GSM is excellent system for cellular telephony

• Professional mobile radio needs appropriate technology

O K

C

SERV 69

F BABC

STOCKHOLMTRAFIK 2


Build PMR by GSM?

• Technical reasons• Direct mode• 300 millisecond call setup• semi-duplex group communication

• Cost reasons• Only high volumes make cellular phones cheaper compared with professional radios

• Easier to develop a TETRA system than modify GSM

• Market strategy reasons• Too small volumes for cellular phone industry

• Too small volumes for GSM infra industry

• Too risky for GSM operators


Spectrum Efficiency200kHz bandwidth

GSM

Half-rate GSM

Traditional PMR 25 kHz

Traditional PMR 12.5 kHz

TETRA

200 kHz carrier8 channels

200 kHz carrier16 channels

25 kHz channel8 channels / 200 kHz

12.5 kHz channels16 channels / 200 kHz

25 kHz carrier4 channels / carrier32 channels / 200 kHz

TETRA DEC02

Documents