Terrestrial Trunked Radio (TETRA); Speech codec for full-rate traffic channel; Part 2: TETRA codec

The present document contains the full specification of the speech codecs for use in the Terrestrial Trunked Radio (TETRA) system. The TETRA codec specified in clauses 4 to 8 is mandatory for all TETRA mobiles and networks. The AMR codec specified in clauses 9 to 12 is optional. If the AMR codec is implemented, the equipment shall conform to the whole of clause 9 to 12.

Prizemni snopovni radio (TETRA) – Govorni kodek za kanal s polno hitrostjo – 2. del: Kodek TETRA

General Information

Status
Published
Publication Date
31-Mar-2006
Current Stage
6060 - National Implementation/Publication (Adopted Project)
Start Date
01-Apr-2006
Due Date
01-Apr-2006
Completion Date
01-Apr-2006

Buy Standard

Standard
SIST EN 300 395-2 V1.3.1:2006
English language
93 pages
sale 10% off
Preview
sale 10% off
Preview

e-Library read for
1 day

Standards Content (sample)

SLOVENSKI STANDARD
SIST EN 300 395-2 V1.3.1:2006
01-april-2006
Prizemni snopovni radio (TETRA) – Govorni kodek za kanal s polno hitrostjo – 2.
del: Kodek TETRA

Terrestrial Trunked Radio (TETRA); Speech codec for full-rate traffic channel; Part 2:

TETRA codec
Ta slovenski standard je istoveten z: EN 300 395-2 Version 1.3.1
ICS:
33.070.10 Prizemni snopovni radio Terrestrial Trunked Radio
(TETRA) (TETRA)
SIST EN 300 395-2 V1.3.1:2006 en

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

---------------------- Page: 1 ----------------------
SIST EN 300 395-2 V1.3.1:2006
---------------------- Page: 2 ----------------------
SIST EN 300 395-2 V1.3.1:2006
ETSI EN 300 395-2 V1.3.1 (2005-01)
European Standard (Telecommunications series)
Terrestrial Trunked Radio (TETRA);
Speech codec for full-rate traffic channel;
Part 2: TETRA codec
---------------------- Page: 3 ----------------------
SIST EN 300 395-2 V1.3.1:2006
2 ETSI EN 300 395-2 V1.3.1 (2005-01)
Reference
REN/TETRA-05059
Keywords
TETRA, radio, codec
ETSI
650 Route des Lucioles
F-06921 Sophia Antipolis Cedex - FRANCE
Tel.: +33 4 92 94 42 00 Fax: +33 4 93 65 47 16
Siret N° 348 623 562 00017 - NAF 742 C
Association à but non lucratif enregistrée à la
Sous-Préfecture de Grasse (06) N° 7803/88
Important notice
Individual copies of the present document can be downloaded from:
http://www.etsi.org

The present document may be made available in more than one electronic version or in print. In any case of existing or

perceived difference in contents between such versions, the reference version is the Portable Document Format (PDF).

In case of dispute, the reference shall be the printing on ETSI printers of the PDF version kept on a specific network drive

within ETSI Secretariat.

Users of the present document should be aware that the document may be subject to revision or change of status.

Information on the current status of this and other ETSI documents is available at

http://portal.etsi.org/tb/status/status.asp

If you find errors in the present document, please send your comment to one of the following services:

http://portal.etsi.org/chaircor/ETSI_support.asp
Copyright Notification
No part may be reproduced except as authorized by written permission.
The copyright and the foregoing restriction extend to reproduction in all media.
© European Telecommunications Standards Institute 2005.
All rights reserved.
TM TM TM

DECT , PLUGTESTS and UMTS are Trade Marks of ETSI registered for the benefit of its Members.

TIPHON and the TIPHON logo are Trade Marks currently being registered by ETSI for the benefit of its Members.

3GPP is a Trade Mark of ETSI registered for the benefit of its Members and of the 3GPP Organizational Partners.

ETSI
---------------------- Page: 4 ----------------------
SIST EN 300 395-2 V1.3.1:2006
3 ETSI EN 300 395-2 V1.3.1 (2005-01)
Contents

Intellectual Property Rights................................................................................................................................7

Foreword.............................................................................................................................................................7

1 Scope........................................................................................................................................................9

2 References................................................................................................................................................9

3 Abbreviations...........................................................................................................................................9

4 Full rate codec........................................................................................................................................10

4.1 Structure of the codec.......................................................................................................................................10

4.2 Functional description of the codec..................................................................................................................12

4.2.1 Pre- and post-processing.............................................................................................................................12

4.2.2 Encoder.......................................................................................................................................................13

4.2.2.1 Short-term prediction............................................................................................................................14

4.2.2.2 LP to LSP and LSP to LP conversion ...................................................................................................14

4.2.2.3 Quantization and interpolation of LP parameters..................................................................................16

4.2.2.4 Long-term prediction analysis...............................................................................................................17

4.2.2.5 Algebraic codebook: structure and search.............................................................................................19

4.2.2.6 Quantization of the gains ......................................................................................................................21

4.2.2.7 Detailed bit allocation ...........................................................................................................................23

4.2.3 Decoder.......................................................................................................................................................23

4.2.3.1 Decoding process..................................................................................................................................24

4.2.3.1.1 Decoding of LP filter parameters ....................................................................................................24

4.2.3.1.2 Decoding of the adaptive codebook vector......................................................................................24

4.2.3.1.3 Decoding of the innovation vector ..................................................................................................25

4.2.3.1.4 Decoding of the adaptive and innovative codebook gains...............................................................25

4.2.3.1.5 Computation of the reconstructed speech........................................................................................25

4.2.3.2 Error concealment.................................................................................................................................25

5 Channel coding for speech .....................................................................................................................26

5.1 General.............................................................................................................................................................26

5.2 Interfaces in the error control structure ............................................................................................................26

5.3 Notations..........................................................................................................................................................28

5.4 Definition of sensitivity classes and error control codes ..................................................................................28

5.4.1 Sensitivity classes.......................................................................................................................................28

5.4.2 CRC codes..................................................................................................................................................28

5.4.3 16-state RCPC codes ..................................................................................................................................30

5.4.3.1 Encoding by the 16-state mother code of rate 1/3.................................................................................30

5.4.3.2 Puncturing of the mother code ..............................................................................................................30

5.5 Error control scheme for normal speech traffic channel...................................................................................31

5.5.1 CRC code....................................................................................................................................................31

5.5.2 RCPC codes................................................................................................................................................31

5.5.2.1 Puncturing scheme of the RCPC code of rate 8/12 (equal to 2/3).........................................................31

5.5.2.2 Puncturing scheme of the RCPC code of rate 8/18 ...............................................................................31

5.5.3 Matrix Interleaving.....................................................................................................................................32

5.6 Error control scheme for speech traffic channel with frame stealing activated................................................33

5.6.1 CRC code....................................................................................................................................................33

5.6.2 RCPC codes................................................................................................................................................34

5.6.2.1 Puncturing scheme of the RCPC code of rate 8/17 ...............................................................................35

5.6.3 Interleaving.................................................................................................................................................35

6 Channel decoding for speech .................................................................................................................35

6.1 General.............................................................................................................................................................35

6.2 Error control structure ......................................................................................................................................35

7 Codec performance.................................................................................................................................36

8 Bit exact description of the TETRA codec.............................................................................................36

ETSI
---------------------- Page: 5 ----------------------
SIST EN 300 395-2 V1.3.1:2006
4 ETSI EN 300 395-2 V1.3.1 (2005-01)

9 AMR speech codec.................................................................................................................................38

10 Channel coding for AMR speech ...........................................................................................................38

10.1 General.............................................................................................................................................................38

10.2 Interfaces in the error control structure ............................................................................................................38

10.3 Notations..........................................................................................................................................................38

10.4 Definition of sensitivity classes and error control codes ..................................................................................38

10.4.1 Sensitivity classes.......................................................................................................................................38

10.4.2 CRC codes..................................................................................................................................................39

10.4.3 16-state RCPC codes ..................................................................................................................................40

10.4.3.1 Encoding by the 16-state mother code of rate 1/3.................................................................................40

10.4.3.2 Puncturing of the mother code ..............................................................................................................41

10.5 Error control scheme for normal AMR speech traffic channel.........................................................................41

10.5.1 CRC code....................................................................................................................................................41

10.5.2 RCPC codes................................................................................................................................................41

10.5.2.1 Puncturing scheme of the RCPC code of rate 8/12 (equal to 2/3).........................................................42

10.5.2.2 Puncturing scheme of the RCPC code of rate 8/18 ...............................................................................42

10.5.3 Matrix Interleaving.....................................................................................................................................42

10.6 Error control scheme for AMR speech traffic channel with frame stealing activated......................................43

10.6.1 Speech frames in stealing mode..................................................................................................................43

10.6.2 CRC code....................................................................................................................................................44

10.6.3 RCPC codes................................................................................................................................................45

10.6.3.1 Puncturing scheme of the RCPC code of rate 14/8 ...............................................................................45

10.6.4 Interleaving.................................................................................................................................................45

11 Channel decoding for AMR speech .......................................................................................................45

11.1 General.............................................................................................................................................................45

11.2 Error control structure ......................................................................................................................................45

12 Bit exact description of the AMR codec FEC........................................................................................46

Annex A (informative): Implementation of speech channel decoding...............................................47

A.1 Algorithmic description of speech channel decoding ............................................................................47

A.1.1 Definition of error control codes ......................................................................................................................47

A.1.1.1 16-state RCPC codes ..................................................................................................................................47

A.1.1.1.1 Obtaining the mother code from punctured code..................................................................................47

A.1.1.1.2 Viterbi decoding of the 16-state mother code of the rate 1/3 ................................................................47

A.1.1.2 CRC codes..................................................................................................................................................48

A.1.1.3 Type-4 bits..................................................................................................................................................48

A.1.2 Error control scheme for normal speech traffic channel...................................................................................48

A.1.2.1 Matrix Interleaving.....................................................................................................................................48

A.1.2.2 RCPC codes................................................................................................................................................48

A.1.2.2.1 Puncturing scheme of the RCPC code of rate 8/12 (equal to 2/3).........................................................49

A.1.2.2.2 Puncturing scheme of the RCPC code of rate 8/18 ...............................................................................49

A.1.2.3 CRC code....................................................................................................................................................49

A.1.2.4 Speech parameters......................................................................................................................................49

A.1.3 Error control scheme for speech traffic channel with frame stealing activated................................................49

A.1.3.1 Interleaving.................................................................................................................................................49

A.1.3.2 RCPC codes................................................................................................................................................49

A.1.3.2.1 Puncturing scheme of the RCPC code of rate 8/17 ...............................................................................50

A.1.3.3 CRC code....................................................................................................................................................50

A.1.3.4 Speech parameters......................................................................................................................................50

A.2 C Code for speech channel decoding .....................................................................................................50

Annex B (informative): Indexes ............................................................................................................51

B.1 Index of C code routines ........................................................................................................................51

B.2 Index of files...........................................................................................................................................54

Annex C (informative): Codec performance........................................................................................55

C.1 General...................................................................................................................................................55

ETSI
---------------------- Page: 6 ----------------------
SIST EN 300 395-2 V1.3.1:2006
5 ETSI EN 300 395-2 V1.3.1 (2005-01)

C.2 Quality....................................................................................................................................................55

C.2.1 Subjective speech quality .................................................................................................................................55

C.2.1.1 Description of characterization tests...........................................................................................................55

C.2.1.2 Absolute speech quality..............................................................................................................................55

C.2.1.3 Effect of input level ....................................................................................................................................55

C.2.1.4 Effect of input frequency characteristic ......................................................................................................55

C.2.1.5 Effect of transmission errors.......................................................................................................................56

C.2.1.6 Effect of tandeming ....................................................................................................................................56

C.2.1.7 Effect of acoustic background noise ...........................................................................................................56

C.2.1.8 Effect of vocal effort...................................................................................................................................56

C.2.1.9 Effect of frame stealing...............................................................................................................................56

C.2.1.10 Speaker and language dependency .............................................................................................................56

C.2.2 Comparison with analogue FM ........................................................................................................................56

C.2.2.1 Analogue and digital systems results..........................................................................................................56

C.2.2.2 All conditions..............................................................................................................................................57

C.2.2.3 Input level...................................................................................................................................................57

C.2.2.4 Error patterns..............................................................................................................................................58

C.2.2.5 Background noise.......................................................................................................................................58

C.2.3 Additional tests.................................................................................................................................................58

C.2.3.1 Types of signals ..........................................................................................................................................58

C.2.3.2 Codec behaviour.........................................................................................................................................58

C.3 Performance of the channel coding/decoding for speech.......................................................................59

C.3.1 Classes of simulation environment conditions .................................................................................................59

C.3.2 Classes of equipment........................................................................................................................................59

C.3.3 Classes of bits...................................................................................................................................................60

C.3.4 Channel conditions...........................................................................................................................................60

C.3.5 Results for normal case ....................................................................................................................................60

C.4 Complexity.............................................................................................................................................61

C.4.1 Complexity analysis.........................................................................................................................................61

C.4.1.1 Measurement methodology.........................................................................................................................61

C.4.1.2 TETRA basic operators ..............................................................................................................................61

C.4.1.3 Worst case path for speech encoder............................................................................................................63

C.4.1.4 Worst case path for speech decoder............................................................................................................64

C.4.1.5 Condensed complexity values for encoder and decoder .............................................................................65

C.4.2 DSP independence............................................................................................................................................66

C.4.2.1 Program control structure ...........................................................................................................................66

C.4.2.2 Basic operator implementation ...................................................................................................................66

C.4.2.3 Additional operator implementation ...........................................................................................................66

C.5 Delay......................................................................................................................................................66

Annex D (informative): Results of the TETRA codec characterization listening and

complexity tests ..............................................................................................67

D.1 Characterization listening test................................................................................................................67

D.1.1 Experimental conditions...................................................................................................................................67

D.1.2 Tables of results ...............................................................................................................................................68

D.2 TETRA codec complexity study ............................................................................................................76

D.2.1 Computational analysis results .........................................................................................................................76

D.2.1.1 TETRA speech encoder..............................................................................................................................76

D.2.1.2 TETRA speech decoder..............................................................................................................................84

D.2.1.3 TETRA channel encoder and decoder ........................................................................................................87

D.2.2 Memory requirements analysis results .............................................................................................................89

D.2.2.1 TETRA speech encoder..............................................................................................................................89

D.2.2.2 TETRA speech decoder..............................................................................................................................90

D.2.2.3 TETRA speech channel encoder.................................................................................................................90

D.2.2.4 TETRA speech channel decoder.................................................................................................................90

Annex E (informative): Description of attached computer files ........................................................91

E.1 Directory C-WORD...............................................................................................................................91

ETSI
---------------------- Page: 7 ----------------------
SIST EN 300 395-2 V1.3.1:2006
6 ETSI EN 300 395-2 V1.3.1 (2005-01)

E.2 Directory C-CODE.................................................................................................................................91

E.3 Directory AMR-Code.............................................................................................................................91

Annex F (informative): Bibliography...................................................................................................92

History ..............................................................................................................................................................93

ETSI
---------------------- Page: 8 ----------------------
SIST EN 300 395-2 V1.3.1:2006
7 ETSI EN 300 395-2 V1.3.1 (2005-01)
Intellectual Property Rights

IPRs essential or potentially essential to the present document may have been declared to ETSI. The information

pertaining to these essential IPRs, if any, is publicly available for ETSI members and non-members, and can be found

in ETSI SR 000 314: "Intellectual Property Rights (IPRs); Essential, or potentially Essential, IPRs notified to ETSI in

respect of ETSI standards", which is available from the ETSI Secretariat. Latest updates are available on the ETSI Web

server (http://webapp.etsi.org/IPR/home.asp).

Pursuant to the ETSI IPR Policy, no investigation, including IPR searches, has been carried out by ETSI. No guarantee

can be given as to the existence of other IPRs not referenced in ETSI SR 000 314 (or the updates on the ETSI Web

server) which are, or may be, or may become, essential to the present document.
Foreword
This European Stand
...

Questions, Comments and Discussion

Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.