Patents
Sitemap › H04 - Electric communication technique › H04M - Telephonic communication › H04M 3 - Automatic or semi-automatic exchanges
Patents for H04M 3 - Automatic or semi-automatic exchanges (99,881)
07/1991
07/25/1991DE4040813A1 Communicatons installation transferring information via interface - contains combination of control unit and transputer (RTM)-based connector unit and measurement modules
07/24/1991EP0438009A1 Method and system for smoothing and monitoring the data rates of asynchronous time division communications
07/24/1991EP0437515A1 Integrated telecommunication system with improved digital voice response
07/24/1991CN1053338A Method of managing traffic flows in wideband integrated services digital telecommunications network, and network for implementing method
07/23/1991US5034975 Voice announcement device for improving functionality of multi-line telephones
07/23/1991US5034947 Whisper circuit for a conference call bridge including talker nulling and method therefor
07/23/1991US5033981 Distributor strip for telecommunication systems having separating contacts
07/23/1991CA1286759C Telephone toll service with advertising
07/23/1991CA1286757C Call data collection and modification of received call distribution
07/17/1991EP0437256A2 Automatic number identification blocking system
07/17/1991EP0436799A2 Communication network with key distribution
07/17/1991CN1053158A Digital key telephone system
07/17/1991CA2032660A1 Line interface circuit
07/16/1991US5033088 Method and apparatus for effectively receiving voice input to a voice recognition system
07/16/1991US5033077 Voice message delivery to unattended station
07/16/1991US5033076 Enhanced privacy feature for telephone systems
07/16/1991CA1286391C Signaling arrangement
07/16/1991CA1286363C Technique for determining the values of circuit elements in a threeterminal equivalent circuit
07/10/1991EP0436345A2 Voice and image communicating apparatus
07/09/1991US5031218 Redundant message processing and storage
07/09/1991US5031211 Communication circuit switching or parallel operation system
07/09/1991US5031210 Telephone apparatus
07/09/1991CA1285983C Telephone subscriber loop overvoltage protection integrated circuit
07/03/1991EP0435449A2 Automated booking of telecommunications calls
07/03/1991EP0435448A2 Arrangement for routing packetized messages
07/03/1991EP0435032A2 Conference system
07/03/1991CN2080271U Automatic adapter for traffic station
07/03/1991CN1013072B Exchange system having originating call restriction function
07/02/1991US5029204 Operational status controller for echo canceling
07/02/1991US5029200 Voice message system using synthetic speech
07/02/1991US5029199 Distributed control and storage for a large capacity messaging system
07/02/1991US5029196 Automated call screening
07/02/1991US5029162 Automatic gain control using root-mean-square circuitry in a digital domain conference bridge for a telephone network
07/02/1991US5029161 Maintenance system for subscriber terminal management data in a packet switched network
07/02/1991CA1285670C Control system for a plurality of telephone sets
06/1991
06/26/1991EP0434239A2 Voice announcement device for improving functionality of multi-line telephones
06/26/1991EP0434071A2 Apparatus for driving a service function unit of a multi-function telephone set
06/26/1991EP0433964A2 Name resolution in a directory database
06/26/1991EP0433782A2 Conference network
06/26/1991EP0433465A1 Personal communication system
06/25/1991US5027393 Voice conference system using echo cancellers
06/25/1991US5027387 Reverse direction calling system
06/25/1991US5027384 Personalized automatic call routing
06/25/1991US5027358 Switch-adjunct communications protocol
06/25/1991US5027341 Station line switching control system
06/23/1991CA2030909A1 Name resolution in a directory database
06/20/1991DE4023992A1 Instrument to create and evaluate artificial telephone traffic - comprising characteristics, controls, voice frequencies, audible signal on multiple channels controlled independently in parallel
06/19/1991EP0432866A2 Line interface unit
06/18/1991US5025468 Computerized system for incoming calls
06/18/1991US5025466 Telephone test instrument
06/18/1991CA1285020C Direct current power supply with an emergency supply activated by a polarity reversal
06/13/1991WO1991009483A1 Anonymous interactive telephone system having direct connect feature
06/13/1991WO1991008637A1 Payphone system
06/13/1991WO1991008572A1 A speech message recording device
06/12/1991EP0431748A2 Telephony system and method for providing ANI and DNIS
06/12/1991EP0431438A1 Flow control procedure for a broadband integrated services digital telecommunication network, and network to realize the procedure
06/12/1991CN2078949U Local battery telephone switchboard
06/11/1991US5023904 Direct telephone dial ordering service
06/11/1991US5023868 Automated call handling apparatus
06/11/1991US5023863 Optical switching system
06/11/1991CA1284845C Communication system using unbalanced communication paths
06/05/1991EP0430534A1 Control of non-locally switched telecommunication services
06/05/1991EP0430342A2 Circuit for setting up conference connections
06/05/1991EP0429770A2 Switchless automatic call distribution system
06/05/1991CA2031182A1 Tip-ring short detector and power shut-down circuit for a telephone line circuit
06/05/1991CA2029141A1 Thermal protection circuit for an integrated circuit subscriber line interface
06/05/1991CA2029138A1 Ring trip detector for a solid state telephone line circuit
06/04/1991US5022070 Switch-adjunct interface
06/04/1991US5022067 Telephone call security system
06/04/1991US5022024 Subscriber RF telephone system for providing multiple speech and/or data signals simultaneously over either a single or a plurality of RF channels
05/1991
05/31/1991WO1991008652A1 Satellite based simulcast paging system
05/30/1991WO1991007838A1 Remote access telephone control system
05/30/1991WO1991007834A1 Communications line testing
05/29/1991EP0429092A1 Integrated digital circuit for processing speech signal
05/29/1991EP0288462B1 Routing of network traffic
05/29/1991CN1012708B Operation mode of charge system of crossbar telephone switchboard
05/28/1991US5020102 Semi-floating AC/DC active termination circuit with current sink
05/28/1991US5020098 Telephone conferencing arrangement
05/28/1991US5020095 Interactive call distribution processor
05/22/1991EP0428448A1 Device for time-programming and for automatic transfer of the calls of a telephone subscriber line
05/22/1991EP0427871A1 Inter-network connection system
05/22/1991EP0427800A1 Interlock circuit for preventing corruption of telephone line signals.
05/22/1991EP0427760A1 Method and apparatus for accessing a facsimile store and forward network.
05/21/1991US5018194 Electronic switching system having call-forwarding function
05/21/1991US5018184 Automated channel test unit
05/21/1991US5018129 Dual rail dilated switching networks
05/21/1991US5018097 Modularly structured digital communications system for interconnecting terminal equipment and public networks, and having operation and reliability programs
05/21/1991US5017917 Restriction of communication service accessibility among subscriber communities
05/21/1991US5017915 Method of enhancing communication setup between a communication station and a telecommunications network
05/16/1991DE4012855C1 Telecommunications lines imitator for monitoring and testing - has electrically looped load inductance auxiliary to decoupling inductance
05/15/1991EP0426737A1 Adaptive routing of network traffic.
05/14/1991CA1284204C Routing of network traffic
05/08/1991EP0426361A2 Coordinated voice and data display in a multiplex communication system
05/08/1991EP0426355A2 Route based network management
05/08/1991EP0425675A1 Ground fault detecting circuit for subscriber lines
05/07/1991US5014315 Digital telephone system
05/07/1991US5014305 Line interface circuit
05/07/1991US5014303 Operator services using speech processing
05/07/1991US5014298 Voice-data telephonic control system
05/07/1991US5014269 Microcomputer integrating a digital subscriber terminal for an integrated service digital network
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