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Source-Controlled Variable-Rate Multimode Wideband Speech Codec

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Source-Controlled Variable-Rate Multimode Wideband Speech Codec 3GPP2 C.S0052-0 Version 1.0 Date: June 11, 2004 1 2 Source-Controlled Variable-Rate Multimode 3 Wideband Speech Codec (VMR-WB) 4 Service Option 62 for Spread Spectrum Systems 5 6 COPYRIGHT 3GPP2 and its Organizational Partners claim copyright in this document and individual Organizational Partners may copyright and issue documents or standards publications in individual Organizational Partner's name based on this document. Requests for reproduction of this document should be directed to the 3GPP2 Secretariat at [email protected]. Requests to reproduce individual Organizational Partner's documents should be directed to that Organizational Partner. See www.3gpp2.org for more information. 7 8 C.S0052-0 Version 1.0 1 Intentionally left blank. C.S0052-0 Version 1.0 1 FOREWORD 2 These technical requirements form a standard for Service Option 62, source-controlled variable-rate 3 multimode two-way wideband speech Service Option (VMR-WB). VMR-WB has a number of 4 operating modes where each mode corresponds to a certain quality and average data rate and all 5 modes are fully compliant with Rate-Set II of CDMA systems. The maximum speech-coding rate of 6 the Service Option 62 is 13.3 kbps. 7 VMR-WB standard is also interoperable with 3GPP/AMR-WB (ITU-T/G.722.2) standard at 12.65, 8 8.85, and 6.60 kbps. The VMR-WB acronym has been chosen to reflect the algorithmic similarities 9 and interoperability between the two codecs. This document further describes the necessary 10 interworking functions for establishing an interoperable interconnection between VMR-WB and AMR- 11 WB. The applications of the AMR-WB interoperable mode and methods for initiation and setup of 12 interoperable calls are beyond the scope of this specification. 13 The VMR-WB standard, while a wideband speech codec by default, is capable of processing 14 narrowband input speech signals and produce narrowband outputs in all modes of operation. 15 Therefore, this document further describes procedures for initialization and call setup using 16 narrowband speech processing capability of VMR-WB codec. 17 This standard does not address the quality or reliability of Service Option 62, nor does it cover equip- 18 ment performance or measurement procedures. 19 3 C.S0052-0 Version 1.0 1 NOTES 2 1. The associated 3GPP2 C.S0053-0, “Recommended Minimum Performance Standard for the 3 variable-rate multimode wideband speech codec, Service Option 62,” provides specifications and 4 measurement methods. 5 2. “Base station” refers to the functions performed on the landline side, which are typically distributed 6 among a cell, a sector of a cell, a mobile switching center, and a personal communications switching 7 center. 8 3. This document uses the following verbal forms: “Shall” and “shall not” identify requirements to be 9 followed strictly to conform to the standard and from which no deviation is permitted. “Should” and 10 “should not” indicate that one of several possibilities is recommended as particularly suitable, without 11 mentioning or excluding others; that a certain course of action is preferred but not necessarily 12 required; or that (in the negative form) a certain possibility or course of action is discouraged but not 13 prohibited. “May” and “need not” indicate a course of action permissible within the limits of the 14 standard. “Can” and “cannot” are used for statements of possibility and capability, whether material, 15 physical, or causal. 16 4. Footnotes appear at various points in this specification to elaborate and further clarify items 17 discussed in the body of the specification. 18 5. Unless indicated otherwise, this document presents numbers in decimal form. 19 Binary numbers are distinguished in the text by the use of single quotation marks. In some tables, 20 binary values may appear without single quotation marks if table notation clearly specifies that 21 values are binary. The character ‘x’ is used to represent a binary bit of unspecified value. For 22 example ‘xxx00010’ represents any 8-bit binary value such that the least significant five bits equal 23 ‘00010’. 24 Hexadecimal numbers (base 16) are distinguished in the text by use of the form 0xhK h, where 25 hK h represents a string of hexadecimal digits. For example, 0x2FA1 represents a number whose 26 binary value is ‘10111110100001’ and whose decimal value is 12913. 27 4 C.S0052-0 Version 1.0 1 NOTES 2 6. The following conventions apply to mathematical expressions in this standard: 3 • x indicates the largest integer less than or equal to x: 1.1= 1, 1.0 = 1, and −1.1 =-2. 4 • x indicates the smallest integer greater than or equal to x: 1.1 = 2, 2.0 = 2, and −1.1 =- 5 1. 6 • x indicates the absolute value of x: − 17 =17, 17 =17. 7 • ⊕ indicates exclusive OR. 8 • min(x, y) indicates the minimum of x and y. 9 • max(x, y) indicates the maximum of x and y. 10 • In figures, ⊗ indicates multiplication. In formulas within the text, multiplication is implicit. For 11 example, if h(n) and pL(n) are functions, then h(n) pL(n) = h(n) ⊗ pL(n). 12 • x mod y indicates the remainder after dividing x by y: x mod y = x - (y x / y ). 13 • round(x) is traditional rounding: round(x) = sign(x) x + 0.5, where 1 x ≥ 0 14 sign()x = . −1 x < 0 15 • ∑ indicates summation. If the summation symbol specifies initial and terminal values, and the 16 initial value is greater than the terminal value, then the value of the summation is 0. For example, 17 if N=0, and if f(n) represents an arbitrary function, then N 18 f(n) = 0. ∑ n=1 19 • The bracket operator, [ ], isolates individual bits of a binary value. VAR[n] refers to bit n of the 20 binary representation of the value of the variable VAR, such that VAR[0] is the least significant bit 21 of VAR. The value of VAR[n] is either 0 or 1. 22 • Unless otherwise specified log(x) denotes logarithm at base 10 throughout this document. 23 5 C.S0052-0 Version 1.0 1 REFERENCES 2 The following standards contain provisions; through reference in this text constitute provisions of this 3 Standard. At the time of publication, the editions indicated were valid. All standards are subject to 4 revision, and parties to agreements based on this Standard are encouraged to investigate the 5 possibility of applying the most recent editions of the standards indicated below. ANSI and TIA 6 maintain registers of currently valid national standards published by them. 7 8 —Normative References: 9 1. ANSI/EIA/TIA-579-A-98, Telecommunications Telephone Terminal Equipment Transmission 10 Requirements for Digital Wireline Telephones, Nov. 1998. 11 2. ITU-T Recommendation G.711, Pulse Code Modulation (PCM) of Voice Frequencies, Vol. 12 III, Geneva, November 1988. 13 3. ITU-T Recommendation G.712, Transmission Performance Characteristics of Pulse Code 14 Modulation, November 2001. 15 4. ITU-T Recommendation P.79, Calculation of loudness ratings for telephone sets, September 16 1999. 17 5. IEEE Standard 269-2002, Standard Method for Measuring Transmission Performance of 18 Analog and Digital Telephone Set, Handsets and Headset, 2002. 19 6. 3GPP2 C.S0003-0 v3.0, Medium Access Control (MAC) Standard for cdma2000 Spread 20 Spectrum Systems, July 2001. 21 7. 3GPP2 C.S0005-0 v3.0, Upper Layer (Layer 3) Signaling Standard for cdma2000 Spread 22 Spectrum Systems, July 2001. 23 8. 3GPP2 C.S0014-0, Enhanced Variable Rate Codec, Speech Service Option 3 for Wideband 24 Spread Spectrum Digital Systems, December 1999. 25 9. 3GPP TS 26.190, AMR Wideband Speech Codec; Transcoding functions, December 2001. 26 10. 3GPP TS 26.173, AMR Wideband Speech Codec; ANSI-C code, March 2002. 27 11. 3GPP TS 26.174, AMR Wideband Speech Codec; Test sequences, December 2001. 28 12. 3GPP TS 26.193, AMR Wideband Speech Codec; Source Controlled Rate Operation, March 29 2001. 30 13. 3GPP TS 26.194, AMR Wideband Speech Codec; Voice Activity Detection (VAD), March 31 2001. 32 14. 3GPP TS 26.192, AMR Wideband Speech Codec; Comfort Noise Aspects, March 2001. 33 15. 3GPP TS 26.191, AMR Wideband Speech Codec; Error Concealment of Lost Frames, 34 March 2002. 35 16. 3GPP TS 26.201, AMR Wideband Speech Codec; Frame Structure, March 2001. 36 17. 3GPP TS 26.202, AMR Wideband Speech Codec; Interface to RAN, March 2001. 37 18. 3GPP TS 26.976, AMR Wideband Speech Codec; Performance characterisation, June 38 2001. 39 —Informative References: 40 19. J. D. Johnston, “Transform Coding of Audio Signals Using Perceptual Noise Criteria,” IEEE 41 Journal on Selected Areas in Communications, vol. 6, no. 2, pp. 314-323, February 1988. 6 C.S0052-0 Version 1.0 1 20. W.B. Kleijn, P. Kroon, and D. Nahumi, “The RCELP speech-coding algorithm,” European 2 Transactions on Telecommunications, Vol. 4, No. 5, pp. 573–582, 1994. 3 21. L.R. Rabiner and R.W. Schaefer, Digital processing of speech signals, Prentice-Hall Int., 4 1978 5 22. Y. Bistritz and S. Pellerm “Immitance Spectral Pairs (ISP) for speech encoding”, in 6 Proceedings of ICASSP'93, pp. II-9 – II-12, 1993. 7 23. P. Kabal and R.P. Ramachandran, “The computation of line spectral frequencies using 8 Chebyshev polynomials”, IEEE Trans. on Acoustics, Speech and Signal Processing, Vol. 34, 9 no. 6, pp. 1419-1426, 1986 10 24. ITU-T Recommendation P.341, Transmission Characteristics for Wideband (150-7000 Hz) 11 Digital Hands-Free Telephony Terminals, February 1998. 12 25. ITU-T Recommendation P.311, Transmission Characteristics for Wideband (150-7000 Hz) 13 Digital Handset Telephones, February 1998.
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