公开(公告)号：DE3586758T2

公开(公告)日：1993-04-22

申请号：DE3586758

申请日：1985-04-30

Applicant: IBM

Inventor： BELLOC JACQUES ,  CHOLAT-NAMY JEAN ,  CHOQUET MICHEL ,  HUON SIMON ,  PILOST DANIEL ,  SPAGNOL VICTOR ,  DE SAINT MICHEL FRANCOIS

IPC: H04L69/40 ,  H04L1/24 ,  H04L12/26

Abstract: A DTE can control the modems attached thereto by transmitting command messages over the data path and analyzing report messages supplied by the modems in return. Each command message is identified by a specific header. A command message intended for a remote modem (34) is intercepted by the local modem (30) and reformatted so as to obtain a supervisory message that is then transmitted at the rate of one bit per baud. A command message intended for a remote multichannel modem (48) is transmitted either by a supervisory message or in the data mode of operation.

公开(公告)号：CA1092654A

公开(公告)日：1980-12-30

申请号：CA282527

申请日：1977-07-12

Applicant: IBM

Inventor： CHOQUET MICHEL ,  PILOST DANIEL ,  VADE ANDRE

IPC: H04L7/00

Abstract: SYNCHRONIZING DEVICE FOR THE RECEIVER CLOCK OF A DATA TRANSMISSION SYSTEM USING PSK MODULATION This invention relates to a new clock synchronizing arrangement for use in -the receiving device of a data transmission system employing PSK modulation. In PSK systems, the received signal x(t), for a given carrier angular frequency .omega.c can be defined by its envelope and its phase r (t) and ?(t), respectively. r(t) and ?(t) can be expressed by: and where x(t) is the Hilbert Transform of x(t). At the optimum signalling instant topt, r(topt) and ?(topt) normalized (without the data) exhibit the minimum variance. The clock adjustment signal is derived from the variance of the envelope or the variance of the phase of the received signal.

公开(公告)号：CH624518A5

公开(公告)日：1981-07-31

申请号：CH831077

申请日：1977-07-06

Applicant: IBM

Inventor： CHOQUET MICHEL ,  PILOST DANIEL ,  VADE ANDRE

IPC: H04J3/14 ,  H04L7/00 ,  H04L7/02 ,  H04L7/033 ,  H04L7/04 ,  H04L7/10 ,  H04L27/22 ,  H04B12/04

Abstract: This invention relates to a new clock synchronizing arrangement for use in the receiving device of a data transmission system employing PSK modulation.

公开(公告)号：DE2729312A1

公开(公告)日：1978-01-19

申请号：DE2729312

申请日：1977-06-29

Applicant: IBM

Inventor： CHOQUET MICHEL ,  PILOST DANIEL ,  VADE ANDRE

IPC: H04J3/14 ,  H04L7/00 ,  H04L7/02 ,  H04L7/033 ,  H04L7/04 ,  H04L7/10 ,  H04L27/22

Abstract: This invention relates to a new clock synchronizing arrangement for use in the receiving device of a data transmission system employing PSK modulation.

公开(公告)号：CA1101078A

公开(公告)日：1981-05-12

申请号：CA282305

申请日：1977-07-08

Applicant: IBM

Inventor： CHOQUET MICHEL

IPC: H03H15/00 ,  H03H19/00 ,  H04B3/06 ,  H04B3/10 ,  H04L25/03

Abstract: DISCRETE FOURIER TRANSFORM EQUALIZER AND METHOD A method of determining the initial values of the coefficients of a transversal equalizer which includes the steps of: transmitting a periodic sequence such as a pseudo-random sequence over a transmission channel; modulating the received signal by means of a time-domain window whose Fourier transform exhibits a relatively flat central peak and has a low value in the vicinity of those frequencies which are multiples of the inverse of the period of the transmitted sequence, which low value may result, for example, from the existence of double zeros in the Fourier transform; calculating the discrete Fourier transform Wk of the signal so modulated; calculating the ratio Fk= where Zk is the discrete Fourier transform of the transmitted sequence; and calculating the inverse discrete Fourier transform of Fk, thereby determining the value of the coefficients cn of the equalizer.

公开(公告)号：DE2728984A1

公开(公告)日：1978-01-19

申请号：DE2728984

申请日：1977-06-28

Applicant: IBM

Inventor： CHOQUET MICHEL

IPC: H03H15/00 ,  H03H19/00 ,  H04B3/06 ,  H04B3/10 ,  H04L25/03 ,  H04L27/00

公开(公告)号：DE2358009A1

公开(公告)日：1974-05-30

申请号：DE2358009

申请日：1973-11-21

Applicant: IBM

Inventor： CHOQUET MICHEL

IPC: H04J13/10 ,  H04L5/00 ,  H04L25/49 ,  H04L27/12 ,  H04Q1/457 ,  H03B ,  H04L27/20

公开(公告)号：DE3788303T2

公开(公告)日：1994-05-19

申请号：DE3788303

申请日：1987-04-01

Applicant: IBM

Inventor： CHOQUET MICHEL ,  SWARTZ KENNETH RAY ,  STATON III JAMES BROOKS

IPC: H04L12/26 ,  H04M11/06

Abstract: A DTE can control the modems attached thereto by transmitting command messages over the data path and analyzing report messages supplied by the modems in return. Each command message is identified by a specific header. A command message intended for a remote modem (34) is intercepted by the local modem (30) and reformatted so as to obtain a supervisory message that is then transmitted at the rate of one bit per baud. A command message intended for a remote multichannel modem (48) is transmitted either by means of a supervisory message or in the data mode of operation. Messages are specifically addressed to individual modems by a special hierarchical address which utilizes information of the network link level on which the desired modem resides together with information as to which terminal (DTE), if any, the desired modem is attached. All locally attached primary modems are assigned an address comprising the link level designation and a first constant. All remotely attached primary modems are assigned an address comprising their link level designation and the first constant. All secondary modems are assigned an address comprising their link level designation and a second constant or, in the event they serve an attached terminal (DTE), the DTE address is used instead of the second constant.

公开(公告)号：DE3788303D1

公开(公告)日：1994-01-13

申请号：DE3788303

申请日：1987-04-01

Applicant: IBM

Inventor： CHOQUET MICHEL ,  SWARTZ KENNETH RAY ,  STATON III JAMES BROOKS

IPC: H04L12/26 ,  H04M11/06

Abstract: A DTE can control the modems attached thereto by transmitting command messages over the data path and analyzing report messages supplied by the modems in return. Each command message is identified by a specific header. A command message intended for a remote modem (34) is intercepted by the local modem (30) and reformatted so as to obtain a supervisory message that is then transmitted at the rate of one bit per baud. A command message intended for a remote multichannel modem (48) is transmitted either by means of a supervisory message or in the data mode of operation. Messages are specifically addressed to individual modems by a special hierarchical address which utilizes information of the network link level on which the desired modem resides together with information as to which terminal (DTE), if any, the desired modem is attached. All locally attached primary modems are assigned an address comprising the link level designation and a first constant. All remotely attached primary modems are assigned an address comprising their link level designation and the first constant. All secondary modems are assigned an address comprising their link level designation and a second constant or, in the event they serve an attached terminal (DTE), the DTE address is used instead of the second constant.

公开(公告)号：DE3586758D1

公开(公告)日：1992-11-19

申请号：DE3586758

申请日：1985-04-30

Applicant: IBM

Inventor： BELLOC JACQUES ,  CHOLAT-NAMY JEAN ,  CHOQUET MICHEL ,  HUON SIMON ,  PILOST DANIEL ,  SPAGNOL VICTOR ,  DE SAINT MICHEL FRANCOIS

IPC: H04L69/40 ,  H04L1/24 ,  H04L12/26

Abstract: Data terminal equipment (10) sends commands identified by specific headers to the modems over a channel, and analyses the return messages. A command to a distant modem (34) is intercepted by the local modem (30) and its format is changed into a supervisory message with a different header, for transmission at the rate of 1 bit per baud. For a distant multichannel modem (48) the command is sent either by way of a supervisory message or in data mode. Second level modems (54,58) also may be monitored by addressed data-mode comands. commands.