`
`INTERNATIONAL TELECOMMUNICATION UNION
`
`
`
`ITU-T
`
`TELECOMMUNICATION
`STANDARDIZATION SECTOR
`OF ITU
`
`
`V.34
`(09/94)
`
`
`DATA COMMUNICATION OVER
`THE TELEPHONE NETWORK
`
`
`A MODEM OPERATING AT DATA
`SIGNALLING RATES OF UP TO 28 800 bit/s
`FOR USE ON THE GENERAL SWITCHED
`TELEPHONE NETWORK AND ON
`LEASED POINT-TO-POINT 2-WIRE
`TELEPHONE-TYPE CIRCUITS
`
`
`ITU-T Recommendation V.34
`(Previously (cid:147)CCITT Recommendation(cid:148))
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`Qualcomm Incorporated v. Rembrandt Wireless Techs. LP.
`IPR2020-00510
`Qualcomm Ex. 1059
`Page 1 of 70
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`FOREWORD
`
`The ITU-T (Telecommunication Standardization Sector) is a permanent organ of the International Telecommunication
`Union (ITU). The ITU-T is responsible for studying technical, operating and tariff questions and issuing Recommen-
`dations on them with a view to standardizing telecommunications on a worldwide basis.
`
`The World Telecommunication Standardization Conference (WTSC), which meets every four years, establishes the
`topics for study by the ITU-T Study Groups which, in their turn, produce Recommendations on these topics.
`
`The approval of Recommendations by the Members of the ITU-T is covered by the procedure laid down in WTSC
`Resolution No. 1 (Helsinki, March 1-12, 1993).
`
`ITU-T Recommendation V.34 was prepared by ITU-T Study Group 14 (1993-1996) and was approved under the WTSC
`Resolution No. 1 procedure on the 20th of September 1994.
`
`___________________
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`In this Recommendation, the expression (cid:147)Administration(cid:148) is used for conciseness to indicate both a telecommunication
`administration and a recognized operating agency.
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`NOTE
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`All rights reserved. No part of this publication may be reproduced or utilized in any form or by any means, electronic or
`mechanical, including photocopying and microfilm, without permission in writing from the ITU.
`
` ITU 1994
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` V.34 (09/94)
`
`CONTENTS
`
`6.3
`6.4
`
`6.5
`6.6
`
`Scope..............................................................................................................................................................
`References......................................................................................................................................................
`Definitions......................................................................................................................................................
`Abbreviations .................................................................................................................................................
`Line Signals....................................................................................................................................................
`5.1
`Data Signalling Rates........................................................................................................................
`5.2
`Symbol Rates ....................................................................................................................................
`5.3
`Carrier Frequencies...........................................................................................................................
`5.4
`Pre-emphasis.....................................................................................................................................
`5.4.1
`Transmit Spectrum Specifications ....................................................................................
`5.4.2
`Selection Method ..............................................................................................................
`DTE Interfaces ...............................................................................................................................................
`6.1
`Synchronous Interfacing (Primary Channel Only) ...........................................................................
`6.2
`Asynchronous Character-mode Interfacing ......................................................................................
`6.2.1
`Primary Channel ...............................................................................................................
`6.2.2
`Secondary Channel ...........................................................................................................
`Half-duplex Mode Interfacing ..........................................................................................................
`Electrical Characteristics of Interchange Circuits.............................................................................
`6.4.1
`Primary Channel ...............................................................................................................
`6.4.2
`Secondary Channel ...........................................................................................................
`Fault Condition on Interchange Circuits...........................................................................................
`Thresholds and Response Times of Circuit 109 ...............................................................................
`6.6.1
`Duplex Mode ....................................................................................................................
`6.6.2
`Half-Duplex Mode............................................................................................................
`Scrambler .......................................................................................................................................................
`Framing ..........................................................................................................................................................
`8.1
`Overview ..........................................................................................................................................
`8.2
`Mapping Frame Switching................................................................................................................
`8.3
`Multiplexing of Primary and Auxiliary Channel Bits.......................................................................
`Encoder ..........................................................................................................................................................
`9.1
`Signal Constellations ........................................................................................................................
`9.2
`Mapping Parameters .........................................................................................................................
`9.3
`Parser ................................................................................................................................................
`9.3.1
`Procedure for b > 12 .........................................................................................................
`Procedure for b ≤ 12 ........................................................................................................
`9.3.2
`Shell Mapper.....................................................................................................................................
`Differential Encoder .........................................................................................................................
`Mapper, Precoder and Trellis Encoder .............................................................................................
`9.6.1 Mapper ..............................................................................................................................
`9.6.2
`Precoder ............................................................................................................................
`9.6.3
`Trellis Encoder..................................................................................................................
`Non-linear Encoder...........................................................................................................................
`9.7
`Start-up Signals and Sequences......................................................................................................................
`10.1
`Signals and Sequences Used in Duplex Operation...........................................................................
`10.1.1
`Phase 1 ..............................................................................................................................
`10.1.2
`Phase 2 ..............................................................................................................................
`10.1.3
`Phases 3 and 4...................................................................................................................
`Signals and Sequences Used in Half-duplex Operation ...................................................................
`10.2.1
`Phase 1 ..............................................................................................................................
`10.2.2
`Phase 2 ..............................................................................................................................
`10.2.3
`Phase 3 ..............................................................................................................................
`10.2.4 Control channel modulation..............................................................................................
`
`9.4
`9.5
`9.6
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`10.2
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`Page
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`11.2
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`11.3
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`11.4
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`11.5
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`11.6
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`11.7
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`11.8
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`12.3
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`12.4
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`12.5
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`11
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`12
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`13
`14
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`Duplex Operating Procedures ........................................................................................................................
`11.1
`Phase 1 (cid:150) Network Interaction..........................................................................................................
`11.1.1 Call Modem ......................................................................................................................
`11.1.2 Answer Modem.................................................................................................................
`Phase 2 (cid:150) Probing/Ranging...............................................................................................................
`11.2.1 Error Free Procedures .......................................................................................................
`11.2.2 Recovery Mechanisms ......................................................................................................
`Phase 3 (cid:150) Equalizer and Echo Canceller Training............................................................................
`11.3.1 Error Free Procedure.........................................................................................................
`11.3.2 Recovery Mechanisms ......................................................................................................
`Phase 4 (cid:150) Final Training ...................................................................................................................
`11.4.1 Error Free Procedure.........................................................................................................
`11.4.2 Recovery Mechanism........................................................................................................
`Retrains.............................................................................................................................................
`11.5.1 Call Modem ......................................................................................................................
`11.5.2 Answer Modem.................................................................................................................
`Rate Renegotiation............................................................................................................................
`11.6.1 Error Free Procedure.........................................................................................................
`11.6.2 Recovery Mechanism........................................................................................................
`Cleardown.........................................................................................................................................
`11.7.1
`Initiating Modem...............................................................................................................
`11.7.2 Responding Modem..........................................................................................................
`Two-wire Leased Line Operation.....................................................................................................
`11.8.1 Call Modem ......................................................................................................................
`11.8.2 Answer Modem.................................................................................................................
`Half-duplex Operating Procedures.................................................................................................................
`12.1
`Phase 1 (cid:150) Network Interaction..........................................................................................................
`12.2
`Phase 2 (cid:150) Probing .............................................................................................................................
`12.2.1 Call Modem as Source Modem.........................................................................................
`12.2.2 Answer Modem as Source Modem...................................................................................
`Phase 3 (cid:150) Primary Channel Equalizer Training................................................................................
`12.3.1
`Source Modem..................................................................................................................
`12.3.2 Recipient Modem..............................................................................................................
`12.3.3 Recipient Modem Error Recovery Procedures .................................................................
`Control Channel Start-up..................................................................................................................
`12.4.1
`Source Modem..................................................................................................................
`12.4.2 Recipient Modem..............................................................................................................
`Primary Channel Resynchronization Procedure ...............................................................................
`12.5.1
`Source Modem..................................................................................................................
`12.5.2 Recipient Modem..............................................................................................................
`12.5.3
`Primary Channel Turn-off.................................................................................................
`Control Channel Resynchronization Procedure................................................................................
`12.6.1
`Source Modem..................................................................................................................
`12.6.2 Recipient Modem..............................................................................................................
`12.6.3 Control Channel Turn-off .................................................................................................
`Primary Channel Retrains.................................................................................................................
`12.7.1 Call Modem (cid:150) Source or Recipient...................................................................................
`12.7.2 Answer Modem (cid:150) Source or Recipient .............................................................................
`Control Channel Retrains..................................................................................................................
`12.8.1
`Initiating Retrain ...............................................................................................................
`12.8.2 Responding to Retrain.......................................................................................................
`Testing Facilities ............................................................................................................................................
`Glossary..........................................................................................................................................................
`14.1 Variables and Parameters used in Data mode (clauses 5 to 9)..........................................................
`
`12.6
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`12.7
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`12.8
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`ii Recommendation V.34 (09/94)
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`Recommendation V.34
`
`Recommendation V.34 (09/94)
`
`
`
`A MODEM OPERATING AT DATA SIGNALLING RATES OF UP
`TO 28 800 bit/s FOR USE ON THE GENERAL SWITCHED TELEPHONE
`NETWORK AND ON LEASED POINT-TO-POINT 2-WIRE
`TELEPHONE-TYPE CIRCUITS
`
`(Geneva, 1994)
`
`1
`
`Scope
`
`This modem is intended for use on connections on general switched telephone networks (GSTNs) and on point-to-point
`2-wire leased telephone-type circuits. The principal characteristics of the modem are as follows:
`a) duplex and half-duplex modes of operation on GSTN and point-to-point 2-wire leased circuits;
`b)
`channel separation by echo cancellation techniques;
`c) quadrature amplitude modulation (QAM) for each channel with synchronous line transmission at
`selectable symbol rates including the mandatory rates of 2400, 3000, and 3200 symbols/s and the optional
`rates of 2743, 2800, and 3429 symbols/s;
`synchronous primary channel data signalling rates of:
`28 800 bit/s;
`(cid:150)
`(cid:150)
`26 400 bit/s;
`(cid:150)
`24 000 bit/s;
`(cid:150)
`21 600 bit/s;
`(cid:150)
`19 200 bit/s;
`(cid:150)
`16 800 bit/s;
`(cid:150)
`14 400 bit/s;
`(cid:150)
`12 000 bit/s;
`(cid:150)
`1 9600 bit/s;
`(cid:150)
`1 7200 bit/s;
`(cid:150)
`1 4800 bit/s;
`(cid:150)
`1 2400 bit/s;
`trellis coding for all data signalling rates;
`an optional auxiliary channel with a synchronous data signalling rate of 200 bit/s, a portion of which may
`be provided to the user as an asynchronous secondary channel;
`adaptive techniques that enable the modem to achieve close to the maximum data signalling rate the
`channel can support on each connection;
`exchange of rate sequences during start-up to establish the data signalling rate;
`automoding to V-Series modems supported by V.32 bis Automode procedures and Group 3 facsimile
`machines.
`
`d)
`
`e)
`f)
`
`g)
`
`h)
`i)
`
`2
`
`References
`
`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 referenced Standards are subject to revision; all users of this Recommendation are therefore
`
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`Recommendation V.34 (09/94)
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`1
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`(cid:150)
`
`(cid:150)
`
`(cid:150)
`
`(cid:150)
`
`(cid:150)
`
`(cid:150)
`
`(cid:150)
`
`(cid:150)
`
`(cid:150)
`
`encouraged to investigate the possibility of applying the most recent editions of the Recommendations and other
`references listed below. A list of currently valid ITU-T Recommendations is regularly published.
`ISO 2110:1989, Information technology (cid:150) Data communications (cid:150) 25-pole DTE/DCE interface connector
`(cid:150)
`and contact number assignments.
`ISO/IEC 11569:1993, Information technology (cid:150) Telecommunications and information exchange between
`systems (cid:150) 26-pole interface connector mateability and contact number assignments.
`ITU-T (CCITT) Recommendation T.30 (1988) (Amended, March 1991), Procedures for document
`facsimile transmission in the general switched telephone network.
`ITU-T Recommendation V.8 (1994), Procedures for starting and ending sessions of data transmission
`over the general switched telephone network.
`ITU-T (CCITT) Recommendation V.10 (1993), Electrical characteristics for unbalanced double-current
`interchange circuits operating at data signalling rates nominally up to 100 kbit/s.
`ITU-T (CCITT) Recommendation V.11 (1993), Electrical characteristics for balanced double-current
`interchange circuits operating at data signalling rates up to 100 kbit/s.
`ITU-T (CCITT) Recommendation V.14 (1988), Transmission of start-stop characters over synchronous
`bearer channels.
`ITU-T (CCITT) Recommendation V.21 (1988), 300 bit per second duplex modem standardized for use in
`the general switched telephone network.
`ITU-T (CCITT) Recommendation V.24 (1988), List of definitions for interchange circuits between data
`terminal equipment (DTE) and data circuit-terminating equipment (DCE).
`ITU-T (CCITT) Recommendation V.25 (1984), Automatic answering equipment and/or parallel
`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 (CCITT) Recommendation V.28 (1993), Electrical characteristics for unbalanced double-current
`interchange circuits.
`ITU-T (CCITT) Recommendation V.32 (1988), 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 circuits.
`ITU-T (CCITT) Recommendation V.32 bis (1991), A duplex modem operating at data signalling rates of
`up to 14 400 bit/s for use on the general switched telephone network and on leased point-to-point 2-wire
`telephone-type circuits.
`ITU-T (CCITT) Recommendation V.42 (1993), Error-correcting procedures
`asynchronous-to-synchronous conversion.
`ITU-T (CCITT) Recommendation V.54 (1988), Loop test devices for modems.
`
`(cid:150)
`
`(cid:150)
`
`(cid:150)
`
`(cid:150)
`
`(cid:150)
`
`for DCEs using
`
`3
`
`Definitions
`
`For the purposes of this Recommendation, the following definitions apply:
`
`auxiliary channel: A 200 bit/s data channel which, along with the primary channel, is multiplexed into the bit stream
`transmitted by the modem. Data conveyed in the auxiliary channel is independent from the primary channel and may
`consist of secondary channel data and modem control data.
`
`constellation shaping: A method for improving noise immunity by introducing a non-uniform two-dimensional
`probability distribution for transmitted signal points. The degree of constellation shaping is a function of the amount of
`constellation expansion.
`
`data mode modulation parameters: Parameters determined during start-up and used during data mode transmission.
`
`frame switching: A method for sending a fractional number of bits per mapping frame, on average, by alternating
`between sending an integer b (cid:150) 1 bits per mapping frame and b bits per mapping frame according to a periodic switching
`pattern.
`
`2
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`Recommendation V.34 (09/94)
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`Page 6 of 70
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`line probing: A method for determining channel characteristics by sending periodic signals, which are analysed by the
`modem and used to determine data mode modulation parameters.
`nominal transmit power: Reference transmit power that is configured by the user. A modem that has negotiated a
`transmit power reduction in Phase 2 of the start-up procedures is said to be transmitting below the Nominal Transmit
`Power.
`non-linear encoding: A method for improving distortion immunity near the perimeter of a signal constellation by
`introducing a non-uniform two-dimensional (2D) signal point spacing.
`precoding: A non-linear equalization method for reducing equalizer noise enhancement caused by amplitude distortion.
`Equalization is performed at the transmitter using precoding coefficients provided by the remote modem.
`pre-emphasis: A linear equalization method where the transmit signal spectrum is shaped to compensate for amplitude
`distortion. The pre-emphasis filter is selected using a filter index provided by the remote modem.
`primary channel: The main data channel which, together with auxiliary channel data, constitutes the bit stream
`transmitted by the modem.
`recipient modem: The modem which receives primary channel data in half-duplex mode.
`secondary channel: A portion of the auxiliary channel that is made available to the user.
`shell mapping: A method for mapping data bits to signal points in a multi-dimensional signal constellation, which
`involves partitioning a two-dimensional signal constellation into rings containing an equal number of points.
`source modem: The modem which transmits primary channel data in half-duplex mode.
`trellis encoding: A method for improving noise immunity using a convolutional coder to select a sequence of subsets in
`a partitioned signal constellation. The trellis encoders used in this Recommendation are all four-dimensional (4D) and
`they are used in a feedback structure where the inputs to the trellis encoder are derived from the signal points.
`
`Abbreviations
`4
`For the purposes of this Recommendation, the following abbreviations are used:
`abs[ ]
`Absolute value
`AMP
`Auxiliary Channel Multiplexing Pattern
`CCITT
`International Telephone and Telegraph Consultative Committee
`CME
`Circuit Multiplication Equipment
`CRC
`Cyclic Redundancy Check
`DCE
`Data Circuit Terminating Equipment
`DPSK
`Differential Phase Shift Keying
`DTE
`Data Terminal Equipment
`GPA
`Generating Polynomial (cid:150) Answer modem
`GPC
`Generating Polynomial (cid:150) Call modem
`GSTN
`General Switched Telephone Network
`IEC
`International Electrotechnical Commission
`ISO
`International Organization for Standardization
`ITU-T
`International Telecommunications Union (cid:150) Telecommunications Standardization Sector
`LSB
`Least Significant Bit
`MSB
`Most Significant Bit
`QAM
`Quadrature Amplitude Modulation
`QPSK
`Quadrature Phase Shift Keying
`RTDEa Round-Trip Delay Estimate (cid:150) Answer modem
`RTDEc Round-Trip Delay Estimate (cid:150) Call modem
`SWP
`Switching Pattern
`
`
`
`
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`Recommendation V.34 (09/94)
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`3
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`5
`
`Line Signals
`
`Data Signalling Rates
`5.1
`The primary channel shall support synchronous data signalling rates of 2400 bit/s to 28 800 bit/s in multiples
`of 2400 bit/s. An auxiliary channel with a synchronous data signalling rate of 200 bit/s may also be optionally supported.
`The primary and auxiliary data signalling rates shall be determined during Phase 4 of modem start-up according to the
`procedures described in 11.4. or 12.4. The auxiliary channel shall be used only when the call and answer modems have
`both declared this capability. The primary channel data signalling rates can be asymmetric.
`
`Symbol Rates
`5.2
`The symbol rate shall be S = (a/c) • 2400 ± 0.01% two-dimensional (2D) symbols per second, where a and c are integers
`from the set specified in Table 1 (in which symbol rates are shown rounded to the nearest integer). The symbol rates
`2400, 3000, and 3200 are mandatory; 2743, 2800, and 3429 are optional. The symbol rate shall be selected during
`Phase 2 of modem start-up according to the procedures described in 11.2 or 12.2. Asymmetric symbol rates are
`optionally supported and shall be used only when the call and answer modems have both declared this capability.
`
`TABLE 1/V.34
`Symbol rates
`
`a
`
`11
`18
`17
`15
`14
`10
`
`c
`
`1
`7
`6
`4
`3
`7
`
`Symbol Rate, S
`
`2400
`2743
`2800
`3000
`3200
`3429
`
`
`
`
`Carrier Frequencies
`5.3
`The carrier frequency shall be (d/e) • S Hz, where d and e are integers. One of two carrier frequencies can be selected at
`each symbol rate, as specified in Table 2, which gives the values of d and e and the corresponding frequencies rounded
`to the nearest integer. The carrier frequency shall be determined during Phase 2 of modem start-up according to the
`procedures specified in 11.2 or 12.2. Asymmetric carrier frequencies shall be supported.
`
`TABLE 2/V.34
`Carrier frequencies versus symbol rate
`
`
`
`Low Carrier
`
`High Carrier
`
`Symbol Rate, S
`
`Frequency
`
`2400
`2743
`2800
`3000
`3200
`3429
`
`1600
`1646
`1680
`1800
`1829
`1959
`
`d
`
`2
`3
`3
`3
`4
`4
`
`e
`
`3
`5
`5
`5
`7
`7
`
`Frequency
`
`1800
`1829
`1867
`2000
`1920
`1959
`
`d
`
`3
`2
`2
`2
`3
`4
`
`e
`
`4
`3
`3
`3
`5
`7
`
`
`
`
`4
`
`Recommendation V.34 (09/94)
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`

`

`5.4
`
`Pre-emphasis
`
`
`
`Transmit Spectrum Specifications
`5.4.1
`The transmit spectrum specifications use a normalized frequency, which is defined as the ratio f/S, where f is the
`frequency in Hz and S is the symbol rate.
`The magnitude of the transmitted spectrum shall conform to the templates shown in Figures 1 and 2 for normalized
`frequencies in the range from (d/e (cid:150) 0.45) to (d/e + 0.45). The transmitted spectrum shall be measured using a 600 Ω
`pure resistive load.
`
`
`α
`
`0
`
`Magnitude (dB)
`
`0
`
`0.2
`
`0.4
`
`0.6
`
`0.8
`
`1.0
`
`Normalized frequency, f(Hz)/S
`
`1.2
`T1400610-94/d01
`
`NOTE (cid:150) Tolerance for transmit spectrum is ± 1 dB.
`
`FIGURE 1/V.34
`Transmit spectra templates for indices 0 to 5
`
`
`
`FIGURE 1/V.34...[D01] = 11 CM (118%)
`
`
`Index
`
`0
`
`1
`
`2
`
`3
`
`4
`
`5
`
`
`
`
`
`
`
`
`TABLE 3/V.34
`Parameter α for indices 0 to 5
`
`α
`
`10 dB
`
`12 dB
`
`14 dB
`
`16 dB
`
`18 dB
`
`10 dB
`
`Recommendation V.34 (09/94)
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`

`

`γ
`
`β
`
`Magnitude (dB)
`
`0
`
`0
`
`0.2
`
`0.4
`
`0.8
`0.6
`Normalized frequency, f(Hz)/S
`
`1.0
`
`1.2
`T1400620-94/d02
`
`NOTE (cid:150) Over the range specified, the tolerance for the transmit spectrum magnitude is ± 1 dB.
`
`FIGURE 2/V.34
`Transmit spectra templates for indices 6 to 10
`
`
`
`FIGURE 2/V.34...[D02] = 11 CM (118%)
`
`
`
`
`
`
`
`Index
`
`16
`
`17
`
`18
`
`19
`
`10
`
`TABLE 4/V.34
`Parameters β and γ for indices 6 to 10
`
`β
`
`0.5 dB
`
`1.0 dB
`
`1.5 dB
`
`2.0 dB
`
`2.5 dB
`
`γ
`
`1.0 dB
`
`2.0 dB
`
`3.0 dB
`
`4.0 dB
`
`5.0 dB
`
`5.4.2
`
`Selection Method
`
`The transmitted spectrum shall be specified by a numerical index. The index shall be provided by the remote modem
`during Phase 2 of start-up by the procedures defined in 11.2. or 12.2.
`
`6
`
`DTE Interfaces
`
`Where external physical interfaces for the interchange circuits are not present, the equivalent functionality of the circuits
`must still be provided (see Table 5).
`
`6
`
`Recommendation V.34 (09/94)
`
`Page 10 of 70
`
`

`

`NOTES
`
`
`
`
`
`
`
`1
`2
`2
`
` 3
`
`
`
`4
`4
`4, 5
`4, 5
`4, 5, 6
`
`
`
`TABLE 5/V.34
`
`Interchange circuits for combined primary and secondary channel interfaces
`
`Interchange Circuit
`
`Description
`
`Signal ground or common return
`Transmitted data
`Received data
`Request to send
`Ready for sending
`
`No.
`
`102
`103
`104
`105
`106
`
`107
`108/1 or
`108/2
`109
`
`Data set ready
`Connect data set to line
`Data terminal ready
`Data channel received line signal detector
`
`113
`114
`115
`125
`133
`140
`141
`142
`
`118
`119
`120
`121
`122
`
`Transmitter signal element timing (DTE source)
`Transmitter signal element timing (DCE source)
`Receiver signal element timing (DCE source)
`Calling indicator
`Ready for receiving
`Loopback/maintenance
`Local loopback
`Test indicator
`
`Transmitted secondary channel data
`Received secondary channel data
`Transmit secondary channel line signal
`Secondary channel ready
`Secondary channel received line signal detector
`
`NOTES
`1 When the modem is not operating in a synchronous mode at the interface, any signals on this circuit shall be disregarded.
`Many DTEs operating in an asynchronous mode do not have a generator connected to this circuit.
`2 When the modem is not operating in a synchronous mode at the interface, this circuit shall be clamped to the OFF
`condition. Many DTEs operating in an asynchronous mode do not terminate this circuit.
`3
`Operation of circuit 133 shall be in accordance with 7.3.1/V.42.
`4
`This circuit is provided where the optional secondary channel is implemented without a separate interface.
`5
`This c