Dual port interface for a computer-based multifunction personal communication system

• US 5,453,986 A
• Filed: 12/03/1993
• Issued: 09/26/1995
• Est. Priority Date: 01/08/1993
• Status: Expired due to Term

• Current Assignee: Multi-Tech Systems Incorporated
• Original Assignee: Multi-Tech Systems Incorporated
• Inventors: Davis, Jeffrey P., Sharma, Raghu
• Primary Examiner(s): Chin, Wellington
• Application Number:
  US08/161,915
• Time in Patent Office: 662 Days
• Field of Search: 370/76, 370/82, 370/62, 379/202, 379/203, 379/204, 379/205, 379/206, 379/201, 379/158
• US Class Current: 370/259
• CPC Class Codes: G10L 19/04 using predictive techniques
• CPC Class Codes: H04L 12/6418 Hybrid transport
• CPC Class Codes: H04L 2012/6424 Access arrangements
• CPC Class Codes: H04L 2012/6427 Subscriber Access Module; Concentrator; Group equipment
• CPC Class Codes: H04L 2012/6459 Multiplexing, e.g. TDMA, CDMA
• CPC Class Codes: H04L 2012/6475 N-ISDN, Public Switched Telephone Network [PSTN]
• CPC Class Codes: H04L 2012/6481 Speech, voice
• CPC Class Codes: H04L 2012/6491 Echo cancellation
• CPC Class Codes: H04L 2012/6494 Silence suppression
• CPC Class Codes: H04L 27/3416 in which the information is carried by both the individual signal points and the subset to which the individual points belong, e.g. using coset coding, lattice coding, or related schemes
• CPC Class Codes: H04L 65/1069 Session establishment or de-establishment
• CPC Class Codes: H04L 65/1101 Session protocols
• CPC Class Codes: H04L 65/70 Media network packetisation
• CPC Class Codes: H04L 65/80 Responding to QoS
• CPC Class Codes: H04L 9/40 Network security protocols
• CPC Class Codes: H04M 1/247 Telephone sets including user guidance or feature selection means facilitating their use user interfaces specially adapted for cordless or mobile telephones H04M1/724
• CPC Class Codes: H04M 1/2473 Telephone terminals interfacing a personal computer, e.g. using an API (Application Programming Interface) details of API H04M7/0021
• CPC Class Codes: H04M 1/2477 for selecting a function from a menu display H04M1/2474 takes precedence
• CPC Class Codes: H04M 1/253 Telephone sets using digital voice transmission
• CPC Class Codes: H04M 1/6033 for providing handsfree use or a loudspeaker mode in telephone sets arrangements for preventing acoustic echo H04M9/08
• CPC Class Codes: H04M 1/6505 : storing speech in digital form
• CPC Class Codes: H04M 11/06 : Simultaneous speech and data transmission, e.g. telegraphic transmission over the same conductors
• CPC Class Codes: H04M 11/064 : Data transmission during pauses in telephone conversation
• CPC Class Codes: H04M 11/068 : using time division multiplex techniques; integrated services digital networks H04Q11/0428
• CPC Class Codes: H04M 2203/4509 : Unified messaging with single point of access to voicemail and other mail or messaging systems unified messaging in packet switching networks H04L51/56
• CPC Class Codes: H04M 2250/62 : user interface aspects of conference calls
• CPC Class Codes: H04M 3/002 : Applications of echo suppressors or cancellers in telephonic connections in two-way loud-speaking telephone systems H04M9/08, echo suppressors or cancellers per se H04B3/20
• CPC Class Codes: H04M 3/42 : Systems providing special services or facilities to subscribers specially adapted for wireless communication networks H04W4/00
• CPC Class Codes: H04M 3/5307 : for recording messages comprising any combination of audio and non-audio components
• CPC Class Codes: H04M 3/533 : Voice mail systems
• CPC Class Codes: H04M 3/567 : Multimedia conference systems
• CPC Class Codes: H04M 7/0033 : Notification or handling of incoming calls by a computer
• CPC Class Codes: H04M 7/006 : Networks other than PSTN/ISDN providing telephone service, e.g. Voice over Internet Protocol (VoIP) , including next generation networks with a packet-switched transport layer H04L65/00 takes precedence; aspects not specific to the type of network H04M3/00; special services in those networks H04M3/42
• CPC Class Codes: H04M 7/128 : Details of addressing, directories or routing tables
• CPC Class Codes: H04M 7/1295 : Details of dual tone multiple frequency signalling
• CPC Class Codes: H04N 1/00204 : with a digital computer or a digital computer system, e.g. an internet server programmed control between transmitter and receiver or between image input and image output device H04N1/32561
• CPC Class Codes: H04N 1/00206 : Transmitting or receiving computer data via an image communication device, e.g. a facsimile transceiver H04N1/00236 takes precedence

Abstract

A personal communications system enables the operator to simultaneously transmit voice and data communication to a remote site. The personal communications system is equipped with two telephone line interfaces to allow connection between two remote sites. The connection between the first remote site and the local site may operate in a voice over data communications mode to simultaneously send compressed voice and data. The connection between the local site and a second site is a voice only connection allowing the first remote site to talk to the second remote site without breaking the data communication connection between the first site and the local site. The second remote site may be a public telephone network. The communication between the first remote site and the second remote site through the local site may also be a data communication connection, or it may also be a voice over data communication connection.

Claims

1. In a multi-function communications system, a method of switching from data communication to voice-over-data communication, comprising the steps of:

invoking a voice over data communication connection between a local site equipped with a local modem and a first remote site equipped with a first remote modem;

receiving a command at the local site from the first remote site to connect the local site to a second remote site;

enabling a voice connection between the local modem and the second remote site in response to receiving the command from the first remote site;

enabling a voice connection between

3. The method according to claim 1 wherein the step of invoking a voice over data communication connection includes the step of sending CCITT V.42 standard modem data packets and supervisory packets constructed as a CCITT V.42 standard modem packet using a header undefined by the CCITT V.42 standard.

4. The method according to claim 1 wherein the step of invoking a voice over data communication connection between a local site equipped with a local modem and a first remote site equipped with a first remote modem includes the steps of:

creating at least one outgoing data packet containing conventional digital data;

creating at least one outgoing voice packet containing digital voice data;

detecting substantially silent periods having absence of voice information in the digital voice data and producing in response thereto a silence flag;

transmitting only outgoing data packets when the silence flag indicates the absence of voice information; and

transmitting both the outgoing voice packets and the outgoing data packets when the silence flag indicates the presence of voice information.

5. The method according to claim 3 wherein the step of invoking voice over data communication connection between a local site equipped with a local modem and a first remote site equipped with a first remote modem further includes the steps of:

receiving local voice signals from a local user;

digitizing the voice signals to produce the digital voice data;

compressing the digital voice data into compressed digital voice data; and

placing the compressed digital voice data into the outgoing data packets.

6. The method according to claim 1 wherein the step of invoking a voice over data communication connection between a local site equipped with a local modem and a first remote site equipped with a first remote modem further includes the steps of invoking a cellular telephone link from the first remote site and periodically transmitting a cellular supervisory packet to maintain the connection between the local site and the first remote site.

2. ) the voice portion of the voice over data connection between the first remote modem and the local modem;

and

2.) the voice connection between the local modem and the second remote site;

such that a voice path is established between the first remote site and the second remote site through the local modem.