H04M 13 - Party-line systems

Patents for H04M 13 - Party-line systems (159)
08/2005
08/17/2005	CN1655642A System and method for selecting a cellular network on a wireless local area network (wlan)
07/2005
07/20/2005	EP1554866A2 Method for rate matching to support incremental redundancy with flexible layer one
07/13/2005	EP1553727A1 System and method for selecting a cellular network on a wireless local area network (WLAN)
06/2005
06/15/2005	CN1206836C Method of detecting trunk calling connection in user part of comprehensive subsiness digital network
05/2005
05/12/2005	WO2005043879A1 A method of making a call tracing of the entire net and the whole process in a soft switch
03/2004
03/17/2004	CN1482820A Mothod for common frequency transmission of WCDMA and GSM system
07/2003
07/08/2003	US6591212 Method for testing continuity of ISUP relay call
06/2003
06/25/2003	CN1112811C Decoding method for video frequency data destroyed by path noise
03/2003
03/05/2003	CN1400804A Speech transmission method of Ethernet port
11/2002
11/20/2002	CN1380788A Telephone system for restaurant and bar
07/2002
07/31/2002	CN2503681Y 数字集团电话 Digital PBX
03/2002
03/20/2002	CN1340953A Shared device for data line and telephone line, and wiring method
02/2002
02/19/2002	CA2206688C Digital transmission system for encoding and decoding attribute data into error checking symbols of main data, and method therefor
12/2001
12/12/2001	CN1326291A Multi-extension telephone
10/2001
10/03/2001	CN1072419C Apparatus and method for supporting line group apparatus remote from line unit
08/2001
08/08/2001	CN2442464Y Telephone caller
07/2001
07/25/2001	CN1305287A Method of detecting trunk calling connection in user part of comprehensive business digital network
05/2001
05/31/2001	US20010002191 Method for testing continuity of ISUP relay call
03/2000
03/28/2000	US6044482 Digital transmission system for encoding and decoding attribute data into error checking symbols of main data
03/21/2000	US6040879 Method for decoding video data corrupted by channel noise
12/1999
12/22/1999	CN1047706C Method for performing continuity check in electronic exchange system
08/1999
08/04/1999	CN2332122Y Switching controller for long-range telephone broadcasting system
07/1999
07/28/1999	CN1224298A Telephone single-line multi-telephone system
12/1998
12/09/1998	CN1201334A Method for decoding video data damaged by channel noise
10/1997
10/15/1997	CN2265045Y Party-line intercall device
10/01/1997	EP0797877A1 Digital transmission system for encoding and decoding attribute data into error checking symbols of main data
10/1996
10/02/1996	CN1132432A Collinear calling telephone system
06/1996
06/20/1996	WO1996019054A1 Digital transmission system for encoding and decoding attribute data into error checking symbols of main data
01/1996
01/30/1996	CA2059736C Automatic numbering identification system
10/1995
10/12/1995	DE4420430C1 Supplying operating voltage to subscriber line connections at exchange
10/10/1995	US5457682 Apparatus and method for supporting a line group apparatus remote from a line unit
02/1995
02/01/1995	CN1098236A Apparatus and method for supporting a line group apparatus remote from a line unit
01/1995
01/11/1995	CN1097267A High-rate capacity-increasing method and system of telephone line
10/1994
10/04/1994	US5353326 Method for performing continuity check in an electronic exchange system
06/1994
06/29/1994	CN2170611Y Party-line telephone
12/1993
12/29/1993	CN1080100A Co-linear main and extension telephone system
12/04/1993	CA2095885A1 Auxiliary telephone signal apparatus activated by touch-tone keys
04/1993
04/28/1993	CN2131259Y Party-line system for multiple group-telephones
01/1993
01/06/1993	CN1067774A Method for performing continuity check in electronic exchange system
11/1992
11/04/1992	CN2121101U Extension of common line telephone
05/1992
05/27/1992	CN2105813U Collinear different number telephone switchover system
03/1992
03/25/1992	CN2100062U Multifunctional connector for syntenic telephone
03/1991
03/20/1991	CN2073634U Calling device between master-auxiliary telephone sets
06/1989
06/28/1989	CN2040285U User terminal distributor for frequency-division calling coline telephone
12/1987
12/29/1987	CA1230949A1 Signal multiplexing circuit
10/1987
10/21/1987	CN87200929U Telephonic system controlled by computer
02/1987
02/24/1987	US4646289 Signal multiplexing circuit
11/1986
11/20/1986	EP0201734A1 Device at a telephone subscriber terminal for disconnecting one out of two alternately and automatically connectable substations by the exchange in case of an undesired loop closure in one of these substations
01/1986
01/08/1986	EP0167351A2 Signal multiplexing circuit
10/1984
10/23/1984	CA1176770A1 Four-party automatic number identification circuit arrangements
01/1982
01/12/1982	CA1116327A1 Party intercept in selective multifrequency ringing systems
02/1980
02/26/1980	CA1072697A2 Method and apparatus for automatically identifying an individual calling party on a multiparty telephone line
12/1979
12/04/1979	CA1067634A1 Line circuit for key telephone systems
10/1979
10/02/1979	CA1063742A1 Telephone ringing control circuits
01/1979
01/02/1979	CA1045733A1 Tone receiver
10/1978
10/10/1978	CA1040332A1 System for control of speech direction in duplex telephone circuits
10/1977
10/04/1977	US4052562 System for control of speech direction in duplex telephone circuits
05/1977
05/24/1977	US4025729 Telephone ringing control circuits
06/1976
06/01/1976	US3961144 Exclusion circuit in key telephone system

1 2