ETSI/Tc EKG
`Released by : ETSI/PT 12
`Release date: February 1992
`
`RELEASE NOTE
`
`Recommendation GSH 06.10
`
`GSM Full Rate Speech Transcoding
`
`New Released version February 92 : 3.2.0 (Release 92, Phase 1)
`
`Previously distributed version
`
`:
`
`2.
`
`3.
`
`0 (Release 1/90)
`
`1. Reason for changes
`
`No changes since the previously distributed version.
`
`Google Ex. 1017, pg. 1
`
`Google Ex. 1017, pg. 1
`
`

`

`Google Ex. 1017, pg. 2
`
`Google Ex. 1017, pg. 2
`
`

`

`ETSI/GSM
`
`Version 3.2.0
`
`GSM recommendation: 06.10
`
`Title: GSM full rate speech transcoding
`
`Date: February 1992
`
`List of contents: 1. General
`
`2. Transmission characteristics
`
`3. Functional description of the RPE-LTP codec
`
`4. Computational details of the RPE-LTP codes
`
`5. Digital test sequences
`
`Annex 1. Codec performance
`
`Annex 2. Subjective relevance of the speech
`coder output bits
`
`Annex 3. Format for test sequence distribution
`
`NOTE: This Recommendation is a reproduction of recommendation
`T/L/O3/11 "13 kbit/s Regular Pulse Excitation - Long Term
`Prediction — Linear Predictive Coder for use in the
`Pan-European Digital Mobile Radio System".
`
`Floppy disks containing the digital test sequences described
`in section 5 can be distributed by ETSI Secretariat on request.
`
`Google Ex. 1017, pg. 3
`
`Google Ex. 1017, pg. 3
`
`

`

`ETSI/GSM
`
`Version 3.2.0
`
`The contact information of the ETSI secretariat is:
`
`ETS I
`
`B.P. 152
`
`F 06561 Valbonne Cedex
`
`France
`
`Tel
`
`+33 92 94 42 00
`
`Fax
`
`+33 93 65 47 16
`
`Language of original: English
`
`Number of pages: 93
`
`Google Ex. 1017, pg. 4
`
`Google Ex. 1017, pg. 4
`
`

`

`ETSI/GSM
`
`GSM 06.10 / page 3
`
`Version 3.2.0
`
`Detailed list of contents
`*************************
`
`1- GENERAL
`
`SCOPE
`OUTLINE DESCRIPTION
`FUNCTIONAL DESCRIPTION OF AUDIO PARTS
`PCM FORMAT CONVERSION
`PRINCIPLES OF THE RPE-LTP ENCODER
`PRINCIPLES OF THE RPE-LTP DECODER
`SEQUENCE AND SUBJECTIVE IMPORTANCE OF ENCODED PARAMETERS
`
`MI
`
`ERI
`
`\IONU'IPUJNH
`
`NFJHlJF‘HFJH
`
`2.1. PERFORMANCE CHARACTERISTICS OF THE ANALOGUE/DIGITAL
`INTERFACES
`2.2. TRANSCODER DELAY
`
`3. EEHQIIQEAL DESCRIEIIQN QE THE BPE-LIR QQDEQ
`
`3.1. FUNCTIONAL DESCRIPTION OF THE RPE—LTP ENCODER
`
`3.1.1. Offset compensation
`3.1.2 Preemphasis
`3.1.3. Segmentation
`3.1.4. Autocorrelation
`3.1.5. Schur Recursion
`3.1.6. Transformation of reflection coefficients to Log.—Area
`Ratios
`3.1.7. Quantization and coding of Log.-Area Ratios
`3.1.8. Decoding of the quantized Log. -Area Ratios
`3.1.9. Interpolation of Log. —Area Ratios
`3.1.10. Tranformation of Log. —Area Ratios into reflection
`coefficients
`3.1.11. Short
`term Analysis Filtering
`3.1.12. Sub-segmentation
`3.1.13. Calculation of the LTP parameters
`3.1.14. Coding/Decoding of the LTP lags
`3.1.15. Coding/Decoding of the LTP gains
`3.1.16. Long term analysis filtering
`3.1.17. Long term synthesis filtering
`3.1.18. Weighting Filter
`3.1.19. Adaptive sample rate decimation by RPE grid selection
`3.1.20. APCM quantization of the selected RPE sequence
`3.1.21. APCM inverse quantization
`3.1.22. RPE grid positioning
`
`Google Ex. 1017, pg. 5
`
`Google Ex. 1017, pg. 5
`
`

`

`ETSI/GSM
`
`GSM 06.10 / page 4
`
`Version 3.2.0
`
`DECODER
`
`. RPE decoding section
`Long Term Prediction section
`Short
`term synthesis filtering section
`Postprocessing
`
`TAIL
`
`F
`
`-
`
`DE
`
`.1. DATA REPRESENTATION AND ARITHMETIC OPERATIONS
`.2. FIXED POINT IMPLEMENTATION OF THE-RPE-LTP CODER
`
`NNNNNNN
`
`NNN
`
`u
`- NN u
`
`
`
`ROGJQGLHPU’NHO
`
`\D\D
`
`Scaling of the input variable
`. Downscaling of the input signal
`. Offset compensation
`Preemphasis
`. Autocorrelation
`. Computation of the reflection coefficients
`Transformation of reflection coefficients to Log.-Area
`Ratios
`Quantization and coding of the Log.—Area Ratios
`Decoding of the coded Log.—Area Ratios
`. Computation of the quantized reflection coefficients
`
`to get the LARp[l..8]
`.1. Interpolation of the LARpp[1..8]
`.2. Computation of the rp[1..8] from the interpolated
`LARp[1..8]
`
`.10.
`.11.
`.12.
`.13.
`.14.
`.15.
`.16.
`.17.
`.18.
`
`term analysis filtering
`Short
`Calculation of the LTP parameters
`Long term analysis filtering
`Weighting filter
`RPE grid selection
`APCM quantization of the selected RPE sequence
`APCM inverse quantization
`RPE grid positioning
`Update of the reconstructed short term.residual signal
`dp[—120..-1]
`
`. FIXED POINT IMPLEMENTATION OF THE RPE-LTP DECODER
`
`. RPE decoding section
`Long term synthesis filtering
`. Computation of the decoded reflection coefficients
`Short
`term synthesis filtering section
`. Deemphasis filtering
`. Upscaling of the output signal
`. Truncation of the output variable
`
`\IChLHIDUJNH
`
`NNNNNNNNN
`#bnbnblhblblbnb
`#1599kalb.nuu.wuwwwww
`
`UJ
`
`¢
`
`4.4. TABLES USED IN THE FIXED POINT IMPLEMENTATION OF THE RPE-LTP
`CODER AND DECODER
`
`Google Ex. 1017, pg. 6
`
`Google Ex. 1017, pg. 6
`
`

`

`ETSI/GSM
`
`GSM 06.10 / page 5
`
`Version 3.2.0
`
`5. DIEIEAL_I§EE_S§QQENQE£
`
`5.1
`5.2
`
`INPUT AND OUTPUT SIGNALS
`CONFIGURATION FOR THE APPLICATION OF THE TEST SEQUENCES
`
`5.2.1. Configuration 1 (encoder only)
`5.2.2. Configuration 2
`(Decoder only)
`
`5.3. TEST SEQUENCES
`
`5.3.1. Test sequences for configuration 1
`5.3.2. Test sequences for configuration 2
`
`ANNEX 1- QQDEQ_EEEEQEMAH§E
`
`INTRODUCTION‘
`A1.l.
`A1.2. SPEECH PERFORMANCE
`
`Al.2.1. Single encoding
`A1.2.2. Speech performance when interconnected with coding systems
`on an analogue basis
`
`A1.2.2.1. Performance with 32 kbit/s ADPCM (G.721)
`Al.2.2.2. Performance with another RPE—LTP codec
`A1.2.2.3. Performance with encoding other than RPE-LTP and 32
`kbit/S ADPCM (G.721)
`
`Al.3. NON-SPEECH PERFORMANCE
`
`A.1.3.1. Performance with single sine waves
`Al.3.2. Performance with DTMF tones
`Al.3.3. Performance with information tones
`A1.3.4. Performance with voice—band data
`
`A1.4. DELAY
`Al.5. REFERENCES
`
`ANNEX 2.
`
`TIVE REL V
`
`E
`
`F
`
`BE H
`
`TP
`
`BIT
`
`ANNEX 3. EQRMAT FQR IESI SEQQENQE DISTRIBQTIQE
`
`A3.l. TYPE OF FILES PROVIDED
`A3.2. FILE FORMAT DESCRIPTION
`
`Google Ex. 1017, pg. 7
`
`Google Ex. 1017, pg. 7
`
`

`

`ETSI/GSM
`
`GSM 06.10 / page 6
`
`Version 3.2.0
`
`1.1. SCOPE
`
`The transcoding procedure specified in this recommendation is
`applicable for the full—rate traffic channel
`(TCH)
`in the Pan—
`European Digital Mobile Radio (DMR) system. The use of this
`transcoding scheme for other applications has not been considered.
`
`In recommendation GSM 06.01, a reference configuration for the
`speech transmission chain of the Pan—European DMR system is shown.
`According to this reference configuration,
`the speech encoder
`takes its input as a 13 bit uniform PCM signal either from the
`audio part of the mobile station or on the network side,
`from the
`PSTN via an 8 bit/A—law to 13 bit uniform PCM conversion. The
`encoded speech at the output of the speech encoder is delivered to
`a channel encoder unit which is specified in Rec.GSM 05.03.
`In the
`receive direction,
`the inverse operations take place.
`
`This recommendation describes the detailed mapping between input
`blocks of 160 speech samples in 13 bit uniform PCM format to
`encoded blocks of 260 bits and from encoded blocks of 260 bits to
`output blocks of 160 reconstructed speech samples.
`The sampling
`rate is 8000 sample/s leading to an average bit rate for the
`encoded bit stream of 13 kbit/s. The coding scheme is the
`so—called Regular Pulse Excitation - Long Term prediction — Linear
`Predictive Coder, here—after referred to as RPE-LTP.
`
`The recommendation also specifies the conversion between A—law PCM
`and 13 bit uniform PCM. Performance requirements for the audio
`input and output parts are included only to the extent that they
`affect the transcoder performance. The recommendation also
`describes the codec down to the bit level,
`thus enabling the
`verification of compliance to the recommendation to a high degree
`of confidence by use of a set of digital test sequences. These
`test sequences are also described and are available on floppy
`disks.
`
`1.2. OUTLINE DESCRIPTION
`
`The recommendation is structured as follows:
`
`Section 1.3 contains a functional description of the audio parts
`including the A/D and D/A functions. Section 1.4 describes the
`conversion between 13 bit uniform and 8 bit A—law samples.
`Sections 1.5 and 1.6 present a simplified description of the
`principles of the RPE—LTP encoding and decoding process
`respectively. In section 1.7,
`the sequence and subjective
`importance of encoded parameters are given.
`
`Google Ex. 1017, pg. 8
`
`Google Ex. 1017, pg. 8
`
`

`

`'ETSI/GSM
`
`GSM 06.10 / page 7
`
`Version 3.2.0
`
`Section 2 deals with the transmission characteristics of the audio
`parts that are relevant for the performance of the RPE—LTP codec.
`Some transmission characteristics of the RPE—LTP codec are also
`specified in section 2. Section 3 presents the functional descrip-
`tion of the RPE—LTP coding and decoding procedures, whereas
`section 4 describes the computational details of the algorithm.
`Procedures for the verification of the correct functioning of the
`RPE—LTP are described in section 5.
`
`Performance and network aspects of the RPE—LTP codec are contained
`in annex 1.
`
`1.3. FUNCTIONAL DESCRIPTION OF AUDIO PARTS
`
`The analogue—to—digital and digital—to-analogue conversion will in
`principle comprise the following elements:
`
`1) Analogue to uniform digital
`
`- microphone,
`— input level adjustment device,
`— input anti—aliasing filter,
`— sample—hold device sampling at 8 kHz,
`- analogue-to—uniform digital conversion to 13 bits
`representation.
`
`The uniform format shall be represented in two's complement.
`
`2) Uniform digital to analogue
`
`— conversion from 13 bit /8kHz uniform PCM to analogue,
`— a hold device,
`— reconstruction filter including x/sin x correction,
`— output level adjustment device,
`- earphone or loudspeaker.
`
`In the terminal equipment,
`
`the A/D function may be achieved either
`
`— by direct conversion to 13 bit uniform PCM format.
`— or by conversion to 8 bit/A—law companded format, based on a
`standard A—law codec/filter according to CCITT rec.
`G.711/7l4,
`followed by the 8-bit to 13—bit conversion
`according to the procedure specified in section 1.4.
`
`For the D/A operation,
`
`the inverse operations take place.
`
`In the latter case it should be noted that the specifications in
`CCITT recommendation G.7l4 are concerned with PCM equipment
`located in the central parts of the network. when used in the
`terminal equipment,
`this specification does not on its own ensure
`sufficient out—of-band attenuation.
`
`Google Ex. 1017, pg. 9
`
`Google Ex. 1017, pg. 9
`
`

`

`ETSI/GSM
`
`GSM 06.10 / page 8
`
`Version 3.2.0
`
`The specification of out—of—band signals is defined in section 2
`between the acoustic signal and the digital interface to take into
`account that the filtering in the terminal can be achieved both by
`electronic and acoustical design.
`
`1.4. PCM FORMAT CONVERSION
`
`The conversion between 8 bit A-law companded format and the 13—bit
`uniform format shall be as defined in CCITT Recommendation G.721,
`section 4.2.1,
`sub—block EXPAND and section 4.2.7,
`sub—block
`COMPRESS. The parameter LAW = 1 should be used.
`
`1.5. PRINCIPLES OF THE RPE—LTP ENCODER
`
`A simplified block diagram of the RPE—LTP encoder is shown in Fig
`1.1.
`In this diagram the coding and quantization functions are not
`shown explicitly.
`
`The input speech frame, consisting of 160 signal samples (uniform
`13 bit PCM samples),
`is first pre—processed to produce an
`offset—free signal, which is then subjected to a first order
`pre—emphasis filter. The 160 samples obtained are then analyzed to
`determine the coefficients for the short term analysis filter (LPC
`analysis). These parameters are then used for the filtering of
`the same 160 samples. The result is 160 samples of the short term
`residual signal. The filter parameters,
`termed reflection
`coefficients, are transformed to log.area ratios, LARS, before
`transmission.
`
`the speech frame is divided into 4
`For the following operations,
`sub—frames with 40 samples of the short term residual signal in
`each. Each sub-frame is processed blockwise by the subsequent
`functional elements.
`
`Before the processing of each sub-block of 40 short term residual
`samples,
`the parame—ters of the long term analysis filter,
`the LTP
`lag and the LTP gain, are estimated and updated in the LTP
`analysis block, on the basis of the current sub—block of the
`present and a stored sequence of the 120 previous reconstructed
`short term residual samples.
`
`A block of 40 long term residual signal samples is obtained by
`subtracting 40 estimates of the short term residual signal
`from
`the short term residual signal itself. The resulting block of 40
`long term residual samples is fed to the Regular Pulse Excitation
`analysis which performs the basic compression function of the
`algorithm.
`
`Google Ex. 1017, pg. 10
`
`Google Ex. 1017, pg. 10
`
`

`

`ETSI/GSM
`
`GSM 06.10 / page 9
`
`Version 3.2.0
`
`the block of 40 input long term
`As a result of the RPE-analysis,
`residual samples are represented by one of 4 candidate
`sub—sequences of 13 pulses each. The subsequence selected is
`identified by the RPE grid position (M). The 13 RPE pulses are
`encoded using Adaptive Pulse Code Modulation (APCM) with
`estimation of the sub—block amplitude which is transmitted to the
`decoder as side information.
`
`The RPE parameters are also fed to a local RPE decoding and recon—
`struction module which produces a block of 40 samples of the quan-
`tized version of the long term residual signal.
`
`By adding these 40 quantized samples of the long term residual to
`the previous block of short term residual signal estimates, a
`reconstructed version of the current short term residual signal is
`obtained.
`
`The block of reconstructed short term residual signal samples is
`then fed to the long term analysis filter which produces the new
`block of 40 short term residual signal estimates to be used for
`the next sub-block thereby completing the feedback loop.
`
`1.6. PRINCIPLES OF THE RPE-LTP DECODER
`
`The simplified block diagram of the RPE—LTP decoder is shown in
`fig 1.2. The decoder includes the same structure as the feed—back
`loop of the encoder.
`In error-free transmission,
`the output of
`this stage will be the reconstructed short term residual samples.
`These samples are then applied to the short term synthesis filter
`followed by the de—emphasis filter resulting in the reconstructed
`speech signal samples.
`
`1.7. SEQUENCE AND SUBJECTIVE IMPORTANCE OF ENCODED PARAMETERS
`
`As indicated in fig 1.1 the three different groups of data are
`produced by the enCoder are:
`
`— the short term filter parameters,
`— the Long Term Prediction (LTP) parameters
`- the RPE parameters
`
`The encoder will produce this information in a unique sequence and
`format, and the decoder must receive the same information in the
`same way. In table 1.1,
`the sequence of output bits bl to b260 and
`the bit allocation for each parameter is shown.
`
`Google Ex. 1017, pg. 11
`
`Google Ex. 1017, pg. 11
`
`

`

`ETSI/GSM
`
`GSM 06.10 / page 10
`
`Version 3.2.0
`
`The different parameters of the encoded speech and their
`individual bits have unequal
`importance with respect to subjective
`quality. Before being submitted to the channel encoder,
`the bits
`have to be rearranged in the sequence importance as given in table
`1.2. The ranking has been determined by subjective testing and the
`procedure used is described in annex 2.
`
`Parameter Parameter
`number
`
`Parameter
`name
`
`Var. Number
`name» of bits
`
`Bit no.
`(LSB—MSB)
`
`FILTER
`
`PARAMETERS
`
`LTP
`PARAMETERS
`
`RPE
`PARAMETERS
`
`LTP
`PARAMETERS
`
`RPE
`PARAMETERS
`
`1
`2
`3
`4
`5
`6
`7
`8
`
`9
`10
`
`11
`12
`13
`14
`
`is
`
`26
`27
`
`28
`29
`30
`31
`
`4i
`
`Log. Area
`ratios
`l - 8
`
`LTP lag
`LTP gain
`
`LAR 1
`LAR 2
`LAR 3
`LAR 4
`LAR 5
`LAR 6
`LAR 7
`LAR 8
`
`N1
`b1
`
`RPE grid position
`Block amplitude
`RPE—pulse no.1
`RPE-pulse no.2
`
`M1
`Xmaxl
`xl(0)
`xl(l)
`
`Elias-pulse no.13
`
`x1 (12)
`
`LTP lag
`LTP gain
`
`N2
`b2
`
`RPE grid position
`Block amplitude
`RPE-pulse no.1
`RPE-pulse no.2
`
`M2
`Xmax2
`x2(0)
`x2(1)
`
`{lion—pulse no.13
`
`x2 (12)
`
`6
`6
`5
`5
`4
`4
`3
`3
`
`7
`2
`
`2
`6
`3
`3
`
`3
`
`7
`2
`
`2
`6
`3
`3
`
`3
`
`— b6
`b1
`- b12
`b7
`b13 - b1?
`his — b22
`b23 — b26
`b27 - b30
`b31 — b33
`b34 - b36
`
`b3? — b43
`b44 - b45
`
`b46 - b47
`b48 - b53
`b54 — b56
`b57 — b59
`
`13903-1392
`
`b93 — b99
`blOO- b101
`
`b102— b103
`b104— b109
`b110- b112
`b113— b115
`
`bl46L'b148
`
`Table 1.1a. Encoder output parameters in order of occurrence and
`bit allocation within the speech frame of 260 bits/20
`ms
`
`Google Ex. 1017, pg. 12
`
`Google Ex. 1017, pg. 12
`
`

`

`ETSI/GSM
`
`GSM 06.10 / page 11
`
`Version 3.2.0
`
`Sub-frame no.3
`
`LTP
`PARAMETERS
`
`RPE
`PARAMETERS
`
`43
`44
`
`45
`46
`47
`48
`
`éé
`
`LTP lag
`LTP gain
`
`N3
`b3
`
`RPE grid position
`Block amplitude
`RPE-pulse no.1
`RPE—pulse no.2
`
`M3
`Xmax3
`x3(0)
`x3(1)
`
`RISE—pulse no.13
`
`x3(12)
`
`7
`2
`
`2
`6
`3
`3
`
`3
`
`bl49- b155
`b156- b157
`
`b158— b159
`b160— b165
`b166— b168
`b169— b17l
`
`13202513204
`
`sGBIfEQme'ESTZ __________
`
`Er};—————————— EB ———— urn—=73;—————————————132 _____6 _____ESE—{nil
`PARAMETERS
`61
`LTP gain
`b4
`2
`b212- b213
`
`RPE
`PARAMETERS
`
`62
`63
`64
`65
`
`7'é
`
`RPE grid position
`Block amplitude
`RPE—pulse no.1
`RPE—pulse no.2
`
`M4
`Xmax4
`X4(0)
`x4(1)
`
`EI'PE—pulse no.13
`
`x4(12)
`
`2
`6
`3
`3
`
`3
`
`b214— b215
`b216- b221
`b222- b224
`b225— b227
`
`b25él'b260
`
`Table 1.1b. Encoder output parameters in order of occurrence and
`bit allocation within the speech frame of 260 bits/20
`ms
`
`Google Ex. 1017, pg. 13
`
`Google Ex. 1017, pg. 13
`
`

`

`ETSI/GSM
`
`GSM 06.10 / page 12
`
`Version 3.2.0
`
`Order of bit
`importance
`
`Parameter
`name
`
`Parameter
`number
`
`Bit number
`
`Class Ia
`
`1
`2,3,4,5
`6
`7'
`8
`
`.
`. 49,50
`
`Class Ib
`
`51,52
`.
`.
`
`182
`
`Log.area ratio 1
`Block amplitude
`Log.area ratio 1
`Log.area ratio 2
`Log.area ratio 3
`Log.area ratio 1
`Log.area ratio 2
`Log.area ratio 3
`Log.area ratio 4
`LTP lag
`Block amplitude
`Log.area ratio 2,5,6
`LTP lag
`LTP lag
`LTP lag
`LTP lag
`Block amplitude
`Log.area ratio 1
`Log.area ratio 4
`Log.area ratio 7
`LTP lag
`
`1
`12,29,46,63
`1
`2
`3
`1
`2
`3
`4
`9,26,43,60
`12,29,46,63
`2,5,6
`9,26,43,60
`9,26,43,60
`9,26,43,60
`9,26,43,60
`12,29,46,63
`1
`4
`7
`9,26,43,60
`
`b6
`b53,b109,b165,b221
`b5
`b12
`b17
`b4
`b11
`b16
`b22
`b43,b99,b155,b211
`b52,b108,bl64,b220
`b10,b26,b30
`b42,b98,b154,b210
`b41,b97,b153,b209
`b40.b96.b152,b208
`b39,b95,b151,b207
`b51,b107,b163,b219
`b3
`b21
`b33
`b38,b94,b150,b206
`
`b25,b29
`5,6
`Log.area ratio 5,6
`10,27,44,61 b45,b101,b157,b213
`LTP gain
`9,26,43,60
`b37,b93,bl49,b205
`LTP lag
`11,28,45,62 b47,b103,b159,b215
`Grid position
`1
`b2
`Log.area ratio 1
`Log.area ratio 2,3,8,4 2,3,8,4
`b9,b15,b36,b20
`Log.area ratio 5,7
`5,7
`b24,b32
`LTP gain
`10,27,44,61
`b44,b100,b156,b212
`Block amplitude
`l2,29,46,63
`b50,b106,b162,b218
`RPE pulses
`l3..25
`b56,b59,..,b92
`RPE pulses
`30..42
`b112,b115,..,b148
`RPE pulses
`47..59
`b168,b171,..,b204
`RPE pulses
`64..76
`b224,b227,..,b260
`Grid position
`11,28,45,62
`b46,b102,b158,b214
`Block amplitude
`12,29,46,63
`b49,b105,b161,b217
`RPE pulses
`13..25
`b55,b58,..,b91
`RPE pulses
`30..42
`blll,b114,..,bl47
`RPE pulses
`47..59
`bl67,b170,..,b203
`RPE pulses
`64..67
`b223,b226,b229,b232
`
`Table 1.2a. Subjective importance of encoded bits (the parameter
`and bit numbers refer to table 1.1)
`
`Google Ex. 1017, pg. 14
`
`Google Ex. 1017, pg. 14
`
`

`

`ETSI/GSM
`
`GSM 06.10 / page 13
`
`Version 3.2.0
`
`Class II
`
`183...
`
`259,260
`
`RPE pulses
`Log.area ratio 1
`Log.area ratio 2,3,6
`Log.area ratio 7
`Log.area ratio 8
`Log.area ratio 8,3
`Log.area ratio 4
`Log.area ratio 4,5
`Block amplitude
`RPE pulses
`RPE pulses
`RPE pulses
`RPE pulses
`Log.area ratio 2,6
`
`68..76
`1
`2,3,6
`7
`8
`8,3
`4
`4,5
`12,29,46,63
`13..25
`30..42
`47..59
`64..76
`2,6
`
`b235,b238,..,b259
`bl
`b8,bl4,b28
`b31
`b35
`b34,b13
`b19
`b18,b23
`b48,b104,b160,b216
`b54,b57,..,b90
`b110,bll3,..,bl46
`b166,b169,..,b202
`b222,b225,..,b258
`b7,b27
`
`Table 1.2b. Subjective importance of encoded hits (the parameter
`and bit numbers refer to table 1.1)
`
`EDIE: The subdivisions in table 1.2 indicate the border between
`protection classes Ia,
`Ib and II as defined in recommendation
`GSM 05.03.
`
`Google Ex. 1017, pg. 15
`
`Google Ex. 1017, pg. 15
`
`

`

`ETSI/GSM
`
`GSM 06.10 / page 14
`
`Version 3.2.0
`
`
`R°fl°°u‘.°n
`Short term
`
`
`
`ooeffments coded as
`LPC
`Log. - Area Ratios
`.
`
`_
`analysrs
`(35 bits/20 ms)
`‘
`
`
`
`
`RPE parameters
`
`
`Short term
`RPE grid
`(47 bitsls ms)
`
`
`
`
`selection
`
`
`analysis
`
`
`processing
`signal
`filter
`and coding
`
`
`
`
`(1) Short term residual
`(2) Long term residual (40 samples)
`(3) Short term reSIdual estimate (40 samples)
`(4) Reconstructed short term residual (40 samples)
`(5) Quantized long term residual (40 samples)
`
`To
`radio
`subsystem
`
`Fi 1.1. Sim lified block dia ram of the RPE - LTP encoder
`
`:
`
`Google Ex. 1017, pg. 16
`
`Il il I|llI i l lIl |I IIIIIIIl| lIII E
`
`
`
`Input
`
`
`RPE grid
`
`decoding and
`positioning
`
`
`LTP parameters
`(9 bits/5 ms)
`
`
`
`Google Ex. 1017, pg. 16
`
`

`

`ETSI/GSM
`
`GSM 06.10 / page 15
`
`Version 3.2.0
`
`I
`
`Réflection coefficients coded
`as Log-Area Ratios
`(3B bits/20 ms)
`
`l IIIl ilPI
`
`
`
`Post —
`
`
`
`
`
`Short term
`RPE grid
`decoding and
`0
`synthesis
`processing
`
`
`
`
`
`positioning
`R E
`fiiter
`
`
`Long term
`
`synthesis
`parameters
`(4? bits/5 ms)
`filter
`
`
`
`psrameters
`(9: bits/5 ms)
`
`From
`radio
`
`subsystem
`
`Fig 1.2. Simglified block diagram of the RPE — LTP decoder
`
`Google Ex. 1017, pg. 17
`
`Google Ex. 1017, pg. 17
`
`

`

`ETSI/GSM
`
`GSM 06.10 / page 16
`
`Version 3.2.0
`
`2. TRANSMISSION CHARACTERISTICS
`
`This section specifies the necessary performance characteristics
`of the audio parts for proper functioning of the speech trancoder.
`Some transmission performance characteristics of the RPE-LTP
`transcoder are also given to assist the designer of the speech
`transcoder function. The information given here is redundant and
`the detailed specifications are contained in recommendation GSM
`11.10.
`
`The performance characteristics are referred to the 13 bit uniform
`PCM interface.
`
`the
`EQTE: To simplify the verification of the specifications,
`performance limits may be referred to an A—law measurement
`interface according to CCITT Rec—ommendation G.711.
`In this
`way, standard measuring equipments for PCM systems can be
`utilized for measurements.
`The relationship between the 13
`bit format and the A—law companded shall follow the
`procedures defined in section 1.4.
`
`2.1. PERFORMANCE CHARACTERISTICS OF THE ANALOGUE/DIGITAL
`INTERFACES
`
`Concerning l) discrimination against out-of-band signals (sending)
`and 2) spurious out-of—band signals (receiving),
`the same
`requirements as defined in ETSI standard TE 04—15 (digital
`telephone, candidate NET33) apply.
`
`2.2. TRANSCODER DELAY
`
`Consider a back to back configuration where the parameters
`generated by the encoder are delivered to the speech decoder as
`soon as they are available.
`
`The transcoder delay is defined as the time interval between the
`instant a speech frame of 160 samples has been received at the
`encoder input and the instant the corresponding 160 reconstructed
`speech samples have been out—put by the speech decoder at an 8 kHz
`sample rate.
`
`The theoretical minimum delay which can be achieved is 20 ms.
`requirement is that the transcoder delay should be less than 30
`ms.
`
`The
`
`Google Ex. 1017, pg. 18
`
`Google Ex. 1017, pg. 18
`
`

`

`ETSI/GSM
`
`GSM 06.10 / page 17
`
`Version 3.2.0
`
`3. FUNCTIONAL DESCRIPTION OF THE RPE-LTP CODEC
`
`The block diagram of the RPE-LTP-coder is shown in fig 3.1. The
`individual blocks are described in the following sections.
`
`3.1. FUNCTIONAL DESCRIPTION OF THE RPE—LTP ENCODER
`
`The £rep;ggefifiing_fiegtign of the RPE—LTP encoder comprises the
`following two sub-blocks:
`
`* Offset compensation (3.1.1)
`* Preemphasis (3.1.2)
`
`The L£g_analxsis_§egtign of the RPE—LTP encoder comprises the
`following five sub—blocks:
`
`****
`
`Segmentation (3.1.3)
`Auto—Correlation (3.1.4)
`Schur Recursion (3.1.5)
`Transformation of reflection coefficients to Log.—Area Ratios
`(3.1.6)
`* Quantization and coding of Log.—Area Ratios (3.1.7)
`
`TheW of the RPE-LTP comprises
`the following four sub—blocks:
`
`* Decoding of the quantized Log.-Area Ratios (LARs)
`* Interpolation of Log.—Area Ratios (3.1.9)
`* Transformation of Log.—Area Ratios into reflection coefficients
`(3.1.10)
`* Short term analysis filtering (3.1.11)
`
`(3.1.8)
`
`The Lang Ierm Predictor (LIE) segtign comprises 4 sub—blocks
`working on subsegments (3.1.12) of the short term residual
`samples.
`
`iii-Il-
`
`Calculation of LTP parameters (3.1.13)
`Coding of the LTP lags (3.1.14) and the LTP gains (3.1.15)
`Decoding of the LTP lags (3.1.14) and the LTP gains (3.1.15)
`Long term analysis filtering (3.1.16), and
`Long term synthesis filtering (3.1.17)
`
`Google Ex. 1017, pg. 19
`
`Google Ex. 1017, pg. 19
`
`

`

`ETSI/GSM
`
`GSM 06.10 / page 18
`
`Version 3.2.0
`
`The B£E_§gggfi;ng_§gggign comprises five different sub—blocks:
`
`*I-l‘l-X-
`
`Weighting filter (3.1.18)
`Adaptive sample rate decimation by RPE grid selection (3.1.19)
`APCM quantization of the selected RPE sequence (3.1.20)
`APCM inverse quantization (3.1.21)
`RPE grid positioning (3.1.22)
`
`PREPR
`
`E
`
`3.1.1. Offset compensation
`
`Prior to the speech encoder an offset compensation,by a notch
`filter is applied in order to remove the offset of the input
`signal so to produce the offset—free signal sof-
`
`sof(k)
`
`= so(k)
`
`- so(k—1) + alpha*sof(k—l)
`
`(3.1.1)
`
`alpha = 32735*2"15
`
`3.1.2. Preemphasis
`
`The signal Sof is applied to a first order FIR preemphasis
`filter leading to the input signal s of the analysis section.
`
`s(k)
`
`= sof(k)
`
`— beta*sof(k—1)
`
`(3.1.2)
`
`beta: 23180*2‘15
`
`P
`
`ALY
`
`E TI
`
`3.1.3. Segmentation
`
`is divided into non—overlapping frames
`The speech signal s(k)
`having a length of T0 = 20 ms
`(160 samples). A new LPG—analysis
`of order p=8 is performed for each frame.
`
`Google Ex. 1017, pg. 20
`
`Google Ex. 1017, pg. 20
`
`

`

`ETSI/GSM
`
`GSM 06.10 / page 19
`
`Version 3.2.0
`
`3.1.4. Autocorrelation
`
`The first p+1 = 9 values of the Auto—Correlation function are
`calculated by
`
`ACF(k)=
`
`152
`>
`’i=k
`
`S(i)S(i-k)
`
`,k = 0,1...,8
`
`(3.2)
`
`3.1.5. Schur Recursion
`
`The reflection coefficients are calculated as shown in Fig 3.2
`using the Schur Recursion algorithm. The term "reflection
`coefficient" comes from the theory of linear prediction of speech
`(LPC), where a vocal tract representation consisting of series of
`uniform cylindrical sections is assumed. Such a representation can
`be described by the reflection coefficents or the area ratios of
`connected sections.
`
`3.1.6. Transformation of reflection coefficients to Log.—Area
`Ratios
`
`The reflection coefficients r(i),
`Schur algorithm, are in the range
`
`(i=1..8), calculated by the
`
`—1 <= r(i) <= + 1
`
`the reflection
`Due to the favourable quantization characteristics,
`coefficients are converted into Log.-Area Ratios which are
`strictly defined as follows:
`
`Logarea(i) = loglo
`
`(—————-—T-—)
`
`(3.3)
`
`Since it is the companding characteristic of this transformation
`that is of importance,
`the following segmented approximation is
`used.
`
`Google Ex. 1017, pg. 21
`
`Google Ex. 1017, pg. 21
`
`

`

`ETSI/GSM
`
`GSM 06.10 / page 20
`
`Version 3.2.0
`
`LAR(i)
`
`.
`|r(1)| <
`;
`r(i)
`= Sign[r(i)]*[2|r(i)l-0.67S] ; 0.675 <= |r(i)| < 0.950
`Sign[r(i)]*[8|r(i)[-6.375]
`; 0.950 <= |r(i)| <
`
`(3.4)
`
`with the result that instead of having to divide and obtain the
`logarithm of particular values, it is merely necessary to
`multiply, add and compare these values.
`
`The following equation (3.5) gives the inverse transformation.
`
`LAR'(i)
`r'(i)=sign[LAR'(i)]*[0.500*|LAR'(i)|
`+0.337500]
`sign[LAR'(i)]*[0.125*|LAR'(i)|
`+0.796875]
`
`;
`
`|LAR'(i)l<O.675
`
`; 0.675<=|LAR'(i)l<l.225
`
`;
`
`l.225<=ILAR'(i)|<=1.625
`
`(3.5)'
`
`3.1.7. Quantization and coding of Log.—Area Ratios
`
`The Log.—Area Ratios LAR(i) have different dynamic ranges and
`different asymmetric distribution densities. For this reason,
`transformed coefficients LAR(i) are limited and quantized
`differently according to the following equation (3.6), with LARC(i)
`denoting the quantized and integer coded version of LAR(i).
`
`the
`
`LARC(i)
`
`= Nint(A(i)*LAR(i)
`
`+ B(i)}
`
`with
`
`Nint{z} :: int{z+sign{z}*0.5}
`
`(3.6)
`
`(3.6a)
`
`Function Nint defines the rounding to the nearest integer value,
`with the coefficients A(i), B(i), and different extreme values of
`LARC(i)
`for each coefficient LAR(i) given in table 3.1.
`
`Google Ex. 1017, pg. 22
`
`Google Ex. 1017, pg. 22
`
`

`

`ETSI/GSM
`
`GSM 06.10 / page 21
`
`version 3.2.0
`
`I Minimum | Maximum |
`I B(i)
`ILAR No 1 l A(i)
`:
`I
`:
`: LARc(i)
`: LARC(i)
`|
`___________________________________________ I
`l
`1 20.000 |
`0.000 |
`—32
`|
`+31
`|
`|
`I 20.000 I
`0.000 I
`-32
`|
`+31
`|
`l
`| 20.000 I
`4.000 I
`—16
`I
`+15
`|
`|
`| 20.000 | —5.000 |
`-16
`|
`+15
`|
`I
`| 13.637 I
`0.184 I
`— 8
`|
`+ 7
`|
`|
`I 15.000 |
`-3.500 |
`— 8
`I
`+ 7
`|
`|
`I
`8.334 I —0.666 |
`— 4
`|
`+ 3
`|
`l
`|
`8.824 | —2.235 I
`- 4
`l
`+ 3
`|
`
`1
`2
`3
`4
`5
`6
`7
`8
`
`R-RM
`
`LT
`
`The current frame of the speech signal s is retained in memory
`until calculation of the LPC parameters LAR(i)
`is completed. The
`frame is then read out and fed to the short term analysis filter
`of order p=8. However, prior to the analysis filtering operation,
`the filter coefficients are decoded and preprocessed by
`interpolation.
`
`3.1.8. Decoding of the quantized Log.-Area Ratios
`
`In this block the quantized and coded Log.—Area Ratios (LARC(i)) are
`decoded according to equation (3.7).
`
`LAR"(i) = ( LARCIi)
`
`— 13(1) )/ A(i)
`
`(3.7)
`
`3.1.9. Interpolation of Log.—Area Ratios
`
`To avoid spurious transients which may occur if the filter
`coefficients are changed abruptly,
`two subsequent sets of
`Log.-Area Ratios are interpolated linearly. Within each frame of
`160 analysed speech samples the short term analysis filter and the
`short term synthesis filter operate with four different sets of
`coefficients derived according to table 3.2.
`
`Google Ex. 1017, pg. 23
`
`Google Ex. 1017, pg. 23
`
`

`

`ETSI/GSM
`
`GSM 06.10 / page 22
`
`Version 3.2.0
`
`I I
`
`+ 0.25*LAR"J(i)
`I 0.75*LAR"J_l(i)
`.
`13...26 I 0.50*LAR"J_l(i) + 0.50*LAR"J(i)
`I 0.25*LAR"J~l(i) + 0.75*LAR"J(i)
`I
`LAR"J(i)
`
`I
`I
`I
`I
`
`3.1.10. Transformation of Log.—Area Ratios into reflection
`coefficients
`
`The reflection coefficients are finally determined using the
`inverse transformation according to equation (3.5).
`
`3.1.11. Short Term Analysis Filtering
`
`The Short term analysis filter is implemented according to the
`lattice structure depicted in fig 3.3.
`
`do(k) = s(k)
`uo(k) = 5(k)
`+ r'i*u _1(k-1) with i=1, ...8
`0110:) = (11-10:)
`ui(k) = ‘11-
`(k—l) + r'i*éi_l<k)
`with i=1,...8
`d(k ) = dyi)
`
`(3.8a)
`(3.8b)
`(3.8c)
`(3.8a)
`(3.8e)
`
`-
`
`EDI T R
`
`LT
`
`E
`
`I
`
`3.1.12. Sub—segmentation
`
`Each input frame of the short term residual signal contains 160
`samples, corresponding to 20 ms. The long term correlation is
`evaluated four times per frame, for each 5 ms subsegment. For
`convenience in the following, we note j=0,...,3 the sub—segment
`number, so that the samples pertaining to the j-th sub—segment of
`the residual signal are now denoted by d(kj+k) with j = 0,...,3; kj =
`k0 + j*40 and k = 0,...,39 where k0 corresponds to the first value of
`the current frame.
`
`Google Ex. 1017, pg. 24
`
`Google Ex. 1017, pg. 24
`
`

`

`ETSI/GSM
`
`GSM 06.10 / page 23
`
`Version 3.2.0
`
`3.1.13. Calculation of the LTP parameters
`
`For each of the four sub-segments a long term correlation lag Nj,
`(j=0,...,3), and an associated gain factor b-,
`(j=0,...,3)
`are determined. For each sub—segment,
`the determination of these
`parameters is implemented in three steps.
`
`1) The first step is the evaluation of the cross—correlation
`Rj(lambda) of the current sub-segment of short term residual
`Signal d(k'+i),(i=‘,...,39) and the previous samples of the
`reconstructed short term residual signal d'(kj+i),
`(i=-120,...,—1):
`
`RjIlambda)
`
`=
`
`j =O,...3
`3.9.
`z_ d(kj+i)*d'(kj+i-lambda); kj = k0 + j*40
`i=0
`lambda = 40,...,120
`
`The cross—correlation is evaluated for lags lambda greater than
`or equal to 40 and less than or equal to 120,
`ie corresponding
`to samples outside the current sub—segment and not delayed by
`more than two sub—segments.
`
`(3.9)
`
`2) The second step is to find the position N- of the peak of
`the cross—correlation function within this interval:
`
`Rj(Nj)
`
`= max { Rj(lambda);
`
`lambda = 40..120 };
`
`3) The third step is the evaluation of the gain factor bj
`according to:
`
`(3.10)
`
`bj =
`with
`
`Rj(Nj)
`
`/ Sj(Nj);
`
`j= 0,...,3
`
`(3.11)
`
`Sj(Nj)
`
`12
`= %:Od'
`
`2
`
`_
`(kj+1—Nj);
`
`.
`j = 0,...,3
`
`(3.12)
`
`Google Ex. 1017, pg. 25
`
`Google Ex. 1017, pg. 25
`
`

`

`ETSI/GSM
`
`GSM 06.10 / page 24
`
`Version 3.2.0
`
`It is clear that the last 120 samples of the reconstructed
`short term residual signal d'(kj+i),(i=—120,...,-1) must be
`retained until the next sub—segment so as to allow the
`evaluation of the relations (3.9),....(3.12).
`
`3.1.14. Coding/Decoding of the LTP lags
`
`The long term correlation lags~Nj.(j=O,...,3) can have values
`in the range (40,...,120), and so must be coded using 7 bits with:
`
`ch = Nj'.
`
`j = 0,...,3
`
`(3.13)
`
`At the receiving end, assuming an error free transmission,
`decoding of these values will restore the actual lags:
`
`the
`
`Nj' =ch;
`
`j =o,...,3
`
`(3.14)
`
`3.1.15. Coding/Decoding of the LTP gains
`
`The long term prediction gains b .(j=0,...,3) are encoded with
`2 bits each, according to the following algorithm:
`
`if
`
`bj <= DLB(i)
`
`then bcj
`
`= 0,
`
`i=0
`
`if DLB(i—l) < bj <= DLB(i)
`
`then bcj
`
`= i;
`
`1:1,2
`
`(3.15)
`
`if DLB(i—l) < bj
`
`then bcj
`
`= 3,
`
`i=3
`
`where DLB(i),(i=O,...,2) denotes the decision levels of the
`quantizer, and bcj represents the coded gain value. Decision
`levels and quantizing levels are given in table 3.3.
`
`I
`I
`I
`I
`QLBIi)
`I
`DLB(i)
`I i I
`|——-| ---------------- |