ITU-T G 160-2012 Voice enhancement devices (Study Group 16)《语音增强设备 16号研究组》.pdf

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1、 International Telecommunication Union ITU-T G.160TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU (06/2012) SERIES G: TRANSMISSION SYSTEMS AND MEDIA, DIGITAL SYSTEMS AND NETWORKS International telephone connections and circuits Apparatus associated with long-distance telephone circuitsVoice enhancem

2、ent devices Recommendation ITU-T G.160 ITU-T G-SERIES RECOMMENDATIONS TRANSMISSION SYSTEMS AND MEDIA, DIGITAL SYSTEMS AND NETWORKS INTERNATIONAL TELEPHONE CONNECTIONS AND CIRCUITS G.100G.199 Transmission planning and the E-model G.100G.109 General Recommendations on the transmission quality for an e

3、ntire international telephone connection G.110G.119 General characteristics of national systems forming part of international connections G.120G.129 General characteristics of the 4-wire chain formed by the international circuits and national extension circuits G.130G.139 General characteristics of

4、the 4-wire chain of international circuits; international transit G.140G.149 General characteristics of international telephone circuits and national extension circuits G.150G.159 Apparatus associated with long-distance telephone circuits G.160G.169Transmission plan aspects of special circuits and c

5、onnections using the international telephone connection network G.170G.179 Protection and restoration of transmission systems G.180G.189 Software tools for transmission systems G.190G.199 GENERAL CHARACTERISTICS COMMON TO ALL ANALOGUE CARRIER-TRANSMISSION SYSTEMS G.200G.299 INDIVIDUAL CHARACTERISTIC

6、S OF INTERNATIONAL CARRIER TELEPHONE SYSTEMS ON METALLIC LINES G.300G.399 GENERAL CHARACTERISTICS OF INTERNATIONAL CARRIER TELEPHONE SYSTEMS ON RADIO-RELAY OR SATELLITE LINKS AND INTERCONNECTION WITH METALLIC LINES G.400G.449 COORDINATION OF RADIOTELEPHONY AND LINE TELEPHONY G.450G.499 TRANSMISSION

7、MEDIA AND OPTICAL SYSTEMS CHARACTERISTICS G.600G.699 DIGITAL TERMINAL EQUIPMENTS G.700G.799 DIGITAL NETWORKS G.800G.899 DIGITAL SECTIONS AND DIGITAL LINE SYSTEM G.900G.999 MULTIMEDIA QUALITY OF SERVICE AND PERFORMANCE GENERIC AND USER-RELATED ASPECTS G.1000G.1999 TRANSMISSION MEDIA CHARACTERISTICS G

8、.6000G.6999 DATA OVER TRANSPORT GENERIC ASPECTS G.7000G.7999 PACKET OVER TRANSPORT ASPECTS G.8000G.8999 ACCESS NETWORKS G.9000G.9999 For further details, please refer to the list of ITU-T Recommendations. Rec. ITU-T G.160 (06/2012) i Recommendation ITU-T G.160 Voice enhancement devices Summary Recom

9、mendation ITU-T G.160 applies to the characteristics, performance and testing of voice enhancement devices (VEDs) for use in digital network-based equipment. Such devices are commonly found in mobile networks and this version of this Recommendation is only applicable to mobile networks. VEDs are def

10、ined as certain signal processing network functions (SPNFs) (such as noise reduction and acoustic echo control) in the digital transmission path that perform voice enhancement functions on voiceband signals that traverse mobile networks. Voice enhancement functions include the control of acoustic ec

11、ho generated by wireless handsets, noise reduction, and the recognition and accommodation of tandem free operation (TFO) and interworking function (IWF) signals. The current version of this Recommendation does not include certain tests that are still under study. In particular, it does not contain a

12、ny objective tests covering voice quality performance of noise reduction functions, although a placeholder for such a test is given. In the meantime, the reader should be aware that voice quality performance of noise reduction functions is not addressed by this version of this Recommendation. Append

13、ix II presents an objective methodology for characterizing the basic effect of noise reduction (NR) methods and is accompanied by a reference ANSI-C source code. Three objective measures are specified for characterizing NR solutions. Recommendation target value ranges in specified conditions are giv

14、en for the measures to serve as basic guidelines for the proper functioning of NR methods. This Recommendation includes an electronic attachment containing: Reference ANSI-C source code and test vectors for implementing Appendix II for noise suppression performance measurement. History Edition Recom

15、mendation Approval Study Group 1.0 ITU-T G.160 2008-06-13 16 1.1 ITU-T G.160 (2008) Amd. 1 2009-11-06 16 1.2 ITU-T G.160 (2008) Amd. 2 2011-03-25 16 2.0 ITU-T G.160 2012-06-29 16 ii Rec. ITU-T G.160 (06/2012) FOREWORD The International Telecommunication Union (ITU) is the United Nations specialized

16、agency in the field of telecommunications, information and communication technologies (ICTs). The ITU Telecommunication Standardization Sector (ITU-T) is a permanent organ of ITU. ITU-T is responsible for studying technical, operating and tariff questions and issuing Recommendations on them with a v

17、iew to standardizing telecommunications on a worldwide basis. The World Telecommunication Standardization Assembly (WTSA), which meets every four years, establishes the topics for study by the ITU-T study groups which, in turn, produce Recommendations on these topics. The approval of ITU-T Recommend

18、ations is covered by the procedure laid down in WTSA Resolution 1. In some areas of information technology which fall within ITU-Ts purview, the necessary standards are prepared on a collaborative basis with ISO and IEC. NOTE In this Recommendation, the expression “Administration“ is used for concis

19、eness to indicate both a telecommunication administration and a recognized operating agency. Compliance with this Recommendation is voluntary. However, the Recommendation may contain certain mandatory provisions (to ensure, e.g., interoperability or applicability) and compliance with the Recommendat

20、ion is achieved when all of these mandatory provisions are met. The words “shall“ or some other obligatory language such as “must“ and the negative equivalents are used to express requirements. The use of such words does not suggest that compliance with the Recommendation is required of any party. I

21、NTELLECTUAL PROPERTY RIGHTS ITU draws attention to the possibility that the practice or implementation of this Recommendation may involve the use of a claimed Intellectual Property Right. ITU takes no position concerning the evidence, validity or applicability of claimed Intellectual Property Rights

22、, whether asserted by ITU members or others outside of the Recommendation development process. As of the date of approval of this Recommendation, ITU had not received notice of intellectual property, protected by patents, which may be required to implement this Recommendation. However, implementers

23、are cautioned that this may not represent the latest information and are therefore strongly urged to consult the TSB patent database at http:/www.itu.int/ITU-T/ipr/. ITU 2013 All rights reserved. No part of this publication may be reproduced, by any means whatsoever, without the prior written permis

24、sion of ITU. Rec. ITU-T G.160 (06/2012) iii Table of Contents Page 1 Scope 1 2 References. 2 3 Terms and definitions . 3 4 Abbreviations and acronyms 4 5 Characteristics of VEDs . 5 5.1 General . 5 5.2 Acoustic echo control (AEC) . 6 5.3 Noise reduction (NR) . 6 5.4 Tandem free operation (TFO) 7 5.5

25、 Interworking functions (IWF) 7 6 Test signals . 7 6.1 General . 7 6.2 Measuring input and output signal levels . 7 6.3 Gaussian white noise 8 7 Tests 8 7.1 Overall VED tests . 8 7.2 Noise reduction tests . 14 7.3 Acoustic echo control tests . 17 8 Conformance and interoperability 22 8.1 Mandatory t

26、ests 23 8.2 Optional tests 23 8.3 Interoperability . 23 Appendix I Information on the function and location of VEDs in mobile networks 24 I.1 VED functionality 24 I.2 VED location 24 I.3 CTM operation . 29 Appendix II Objective measures for the characterization of the basic functioning of noise redu

27、ction algorithms 30 II.1 Introduction 30 II.2 Notations . 30 II.3 Test signals . 31 II.4 Objective measures for characterization of NR algorithm effect . 32 II.5 Recommendation values for SNRI, TNLR and DSN 38 II.6 Reference software . 38 iv Rec. ITU-T G.160 (06/2012) Page Appendix III Properties of

28、 level measurement devices 39 III.1 Introduction 39 III.2 Measurement of signal level . 40 III.3 Transition time for measurement device with exponential averaging 44 III.4 Transition time for RMS measurement device . 48 III.5 Comparing the levels of two signals (exponential averaging) . 49 III.6 Com

29、paring the levels of two signals (RMS method) . 50 III.7 Artificial speech signal in noise . 51 III.8 Conclusions 55 Appendix IV One-octave filters for the AEC comfort noise test 56 IV.1 Introduction 56 IV.2 IIR realization . 57 IV.3 FIR realization 59 Bibliography. 62 Electronic attachment: Referen

30、ce ANSI-C source code and test vectors for implementing Appendix II for noise suppression performance measurement. Rec. ITU-T G.160 (06/2012) 1 Recommendation ITU-T G.160 Voice enhancement devices1 Scope This Recommendation applies to the characteristics, performance and testing of voice enhancement

31、 devices (VEDs) for use in digital network-based equipment. Such devices are commonly found in mobile networks, and this version of the Recommendation is only applicable for mobile networks. VEDs are defined as certain signal processing network functions (SPNFs) (such as noise reduction and acoustic

32、 echo control) in the digital transmission path that perform voice enhancement functions on voiceband signals that traverse mobile networks. Possible locations for VEDs located in mobile networks are shown in Appendix I. Voice enhancement functions covered by this Recommendation include the control

33、of acoustic echo generated by wireless handsets, noise reduction, and the recognition and accommodation of tandem free operation (TFO) and interworking function (IWF) signals. The purpose of this Recommendation is to define certain performance constraints for VEDs and, where appropriate, to define l

34、aboratory tests that may be performed on a VED to verify that these constraints are met. A VED that satisfies all the constraints and passes all of the tests in this Recommendation should ensure (but will not guarantee) that the pre-existing standard of the overall network performance (e.g., the tra

35、nsmission of speech, voiceband data and other voiceband signals, ISDN, etc.) is not degraded when the VED is installed in the network. This Recommendation also describes the general characteristics of VEDs and indicates what characteristics are important to provide acceptable performance in the netw

36、ork. Issues relating to the interaction of VEDs with other network and subscriber equipment are also discussed in this Recommendation. This Recommendation does not define a standard algorithm for voice enhancement functions. Nor does it apply to either electrical echo control (governed by ITU-T G.16

37、8) or automatic level control (governed by b-ITU-T G.169). Note that VEDs may be incorporated into other network equipment, such as the transcoder or electrical echo canceller. In this case, the performance requirements of this Recommendation refer to the performance of the VED only. Note that some

38、terminal devices (e.g., mobile stations) incorporate voice enhancement functions (acoustic echo control, noise reduction, etc.) that are similar to those performed by the VED. This Recommendation does not apply to functions contained in these terminal devices. 2 Rec. ITU-T G.160 (06/2012) 2 Referenc

39、es The following ITU-T Recommendations and other references contain provisions which, through reference in this text, constitute provisions of this Recommendation. At the time of publication, the editions indicated were valid. All Recommendations and other references are subject to revision; users o

40、f this Recommendation are therefore encouraged to investigate the possibility of applying the most recent edition of the Recommendations and other references listed below. A list of the currently valid ITU-T Recommendations is regularly published. The reference to a document within this Recommendati

41、on does not give it, as a stand-alone document, the status of a Recommendation. ITU-T G.164 Recommendation ITU-T G.164 (1988), Echo suppressors. ITU-T G.168 Recommendation ITU-T G.168 (2012), Digital network echo cancellers. ITU-T P.50 Recommendation ITU-T P.50 (1999), Artificial voices. ITU-T P.501

42、 Recommendation ITU-T P.501 (2000), Test signals for use in telephonometry. ITU-T P.800 Recommendation ITU-T P.800 (1996), Methods for subjective determination of transmission quality. ITU-T P.830 Recommendation ITU-T P.830 (1996), Subjective performance assessment of telephone-band and wideband dig

43、ital codecs. ITU-T P.835 Recommendation ITU-T P.835 (2003), Subjective test methodology for evaluating speech communication systems that include noise suppression algorithm. ITU-T Q.24 Recommendation ITU-T Q.24 (1988), Multifrequency push-button signal reception. ITU-T Q.143 Recommendation ITU-T Q.1

44、43 (1988), Specifications of signalling system No. 5 Line signal sender. ITU-T Q.144 Recommendation ITU-T Q.144 (1993), Specifications of signalling system No. 5 Line signal receiver. ITU-T Q.271 Recommendation ITU-T Q.271 (1988), Specifications of signalling system No. 6 Section 5: Continuity check

45、 of the speech path. ITU-T Q.724 Recommendation ITU-T Q.724 (1988), Specifications of signalling system No. 7 Signalling procedures. ITU-T V.8 Recommendation ITU-T V.8 (2000), Procedures for starting sessions of data transmission over the public switched telephone network. ITU-T V.18 Recommendation

46、ITU-T V.18 (2000), Operational and interworking requirements for DCEs operating in the text telephone mode. ITU-T V.21 Recommendation ITU-T V.21 (1988), 300 bits per second duplex modem standardized for use in the general switched telephone network. ITU-T V.25 Recommendation ITU-T V.25 (1996), Autom

47、atic answering equipment and general procedures for automatic calling equipment on the general switched telephone network including procedures for disabling of echo control devices for both manually and automatically established calls. ITU-T V.27 ter Recommendation ITU-T V.27 ter (1988), 4800/2400 b

48、its per second modem standardized for use in the general switched telephone network. ITU-T V.32 Recommendation ITU-T V.32 (1993), A family of 2-wire, duplex modems operating at data signalling rates of up to 9600 bit/s for use on the general switched telephone network and on leased telephone-type ci

49、rcuits. Rec. ITU-T G.160 (06/2012) 3 ETSI TS 128 062 ETSI TS 128 062 V7.0.0 (2007), Digital cellular telecommunications system (Phase 2+); Universal Mobile Telecommunications System (UMTS); Inband Tandem Free Operation (TFO) of speech codecs; Service description; Stage 3. IEC 61260 IEC 61260:1995, Electroacoustics Octave-band and fractional-octave-band filters. TIA-825-A ANSI/TIA-825-A (2003), A Frequency Shift Keyed Modem for Use on the Public Switched Telephone Network.