Standardisation for Emergency Communications ETSI Project TETRA

Presentation Transcript

Brian Oliver

EPT Chairman

EMTEL Workshop, February 2002

As it looked in 1989...

The overall PMR market in Europe in the late 1980’s varied country to country - successful public cellular systems seemed to hold back PMR development.
But the demand existed, particularly amongst Public Safety and other ‘professional’ user organisations.
The EC identified, via a number of studies (e.g the ‘SAGATEL Report’), that the remedy was to promote the better sharing of resources via advanced trunked radio systems making the fullest use of the developing digital technology, and if possible to allocate new frequencies.

So what happened?

Analogue trunked radio systems continued to be successfully implemented during the early 1990’s.
ETSI in parallel pursued the development of a digital PMR standard (TETRA).
A number of proprietary digital specifications were also developed (iDEN, Rubis/Acropol, Tetrapol, EDACS, etc.)

TErrestrial Trunked Radio- a chronology

- Work commenced in ETSI on ‘MDTRS’ in 1989

- Consensus on TDMA technology reached in 1991 with 4 timeslots in 25 kHz bandwidth

- First phase standards completed 1995

Harmonized frequencies allocated across Europe (CEPT/NATO 1996)
Second phase standards completed Nov 1997
First TETRA systems installed 1997
Work on Release 2 commenced in late 2000.

Development of a Standard

TETRA features were user-led at the earliest definition stage.
Particular contributions were, and continue to be, made by Public Safety users throughout the development of the TETRA Standard.
Thus TETRA was able to meet the ‘Schengen’ requirements for public safety use.
Release 2 provides further enhancements such as higher speed data.
TETRA is therefore a candidate for both narrow-band and wide-band emergency communications systems.

TETRA ‘Release 2’

Enhancement areas in the work programme:

An increase in data throughput (up to 10 times)
Additional voice codecs for enhanced voice quality and interworking between GSM and UMTS/3G
Air Interface enhancements to optimise

spectrum efficiency
network capacity
system performance
size if terminals and battery life

Range extension for ‘ground to air’, ‘rural telephony’, and possible ‘maritime’ use, etc.
TETRA network interworking between GSM, GPRS, UMTS/3G
Evolution of TETRA SIM towards the USIM platform

What drives the need for very high-speed data?

Video images at fast refresh rate?
Accurate and high-detail fixed images - e.g. fingerprints?
Medical data from remote and mobile units with security?
Internet access on the move, with very fast download of data?
Internet speech on the move?
Integration with 3G?

0

100

200

300

400

2000 kb/s

How Do Data Rates Compare ?

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 (Release 1) 28.8 kb/s

TETRA (Release 2) <400 kb/s

Voice and Data

The ability to share a radio channel between voice and data offers great advantages to the professional user.
Where technology offers the option of apparent simultaneous transmission of voice and data then the impact on operational practice can be significant particularly for police and other emergency services.

Priority Usage

For emergency service users there may be a requirement for senior officers to have priority access to the radio resource.
For resources that are shared by more than one service resource allocation and retention may need to be prioritised.
Emergency service users in addition look for what they perceive to be “instant” voice communications in an emergency.
TETRA achieves this by using combinations of priority and other supplementary services.

Supplementary Services - Public Safety priorities

- 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

Direct Mode Communications

Allows direct terminal to terminal communication without using the network.
Can also be arranged so that terminals remain in contact with the network either directly or via a gateway.
Emergency Services value this facility (e.g. for possible ‘fireground’ use) and have actively supported its development.

Extending the Network

Making full use of the possibilities offered by direct mode communications and associated repeaters and network gateways.
Difficult/costly to cover terrain becomes accessible to network users.
Areas around national borders, where network coverage from either side may be poor, can be made operationally accessible to security/public safety services.

Open Channel

The traditional method of operation for some Emergency Services for many years.
The option of dedicating a resource (radio channel) will always exist even if it causes problems.
TETRA can offer “pseudo” open channel by combining supplementary services and retaining network control of the resource.

Video

Increased data rates, the ability to concatenate resources, advances in picture formatting and coding, make quality video a realistic option.
This opens up new applications opportunities for police, fire, paramedic and other services.