t4.asc

传真编程的一些文档

         The text approved is:
         Fascicle VII.3 - Rec. T.4
         4.3    Extended two-dimensional coding scheme
               The basic facsimile coding scheme specified in S 2.2 of Recommendation  T.6
         may be used as an option in Group 3 facsimile. This coding scheme is  limited  to
         the use of the Error Correction Mode specified in S 3.3.
         4.4    Error limiting mode
               One-dimensional coding scheme with the division of scan line into parts.
               The one-dimensional coding scheme with  the  division  of  scan  line  into
         parts is an optional extension of the one-dimensional coding scheme specified  in
         Annex B.
         5      Modulation and demodulation
               Group 3 apparatus operating  on  the  general  switched  telephone  network
         shall utilize the modulation, scambler, equalization and timing  signals  defined
         in Recommendation V.27 ter, specifically SS 2, 3, 7, 8, 9, 11 and the Appendix.
         5.1    The training signal to be used shall be the long  training  sequence  with
         protection against talker echo (see  Recommendation  V.27  ter,  S  2.5.1,  Table
         3/V.27 ter).
         5.2    The data signalling rates to be used are 4800  bit/s  and  2400  bit/s  as
         defined in Recommendation V.27 ter.
               Note 1