Method and apparatus for sending faxes over analog cellular

• US 5,752,199 A
• Filed: 12/18/1995
• Issued: 05/12/1998
• Est. Priority Date: 12/18/1995
• Status: Expired due to Term

• Current Assignee: Paradyne Corporation (Dasan Networks Incorporated)
• Original Assignee: Paradyne Corporation (Dasan Networks Incorporated)
• Inventors: Scott, Robert Earl
• Primary Examiner(s): Bost, Dwayne D.
• Assistant Examiner(s): TROST IV, WILLIAM GEORGE
• Application Number:
  US08/573,739
• Time in Patent Office: 876 Days
• Field of Search: 379/58, 379/59, 379/93, 379/97, 379/98, 379/100, 379/53.01, 379/93.28, 379/93.31, 379/100.01, 379/100.15, 379/100.16, 379/100.13, 379/93.14, 455/33.1, 455/550, 455/556, 455/557, 455/422, 375/222
• US Class Current: 455/557
• CPC Class Codes: H04N 1/00307 with a mobile telephone apparatus constructional features of portable telephone sets H04M1/0202; mobile radio systems H04W84/00
• CPC Class Codes: H04N 2201/33357 Compression mode
• CPC Class Codes: H04W 76/10 Connection setup
• CPC Class Codes: H04W 88/14 Backbone network devices
• CPC Class Codes: H04W 88/16 Gateway arrangements

Abstract

A cellular modem is configured in one of two modes of fax operation: a standard fax mode or an extended fax mode. In the standard fax mode, the cellular modem completes calls as in the prior art. In the extended fax mode, fax information is transmitted over a cellular-portion of the cellular fax call using a "2-D" fax compression scheme and a data modulation as specified in AT&T Paradyne'"'"'s "Enhanced Throughput Cellular (ETC) Protocol". In this mode of operation, "AT-commands" related to establishing the fax connection are transmitted from the cellular modem to a Mobile Switching Center (MSC) that includes a cellular modem pool. This allows fax-capable terminal equipment at the mobile end of the connection to communicate directly with a far-end fax-capable modem in the MSC notwithstanding the presence of an analog modem at the mobile end.

Claims

1. A method for use in data communications equipment operating on the analog cellular network, the method comprising the steps of;

receiving through a data terminal equipment port of the data communications equipment a data signal representing a predefined modem command;

classifying the predefined modem command as a local command or a remote command;

if a local command, operating on the predefined modem command; and

if a remote command, transmitting the predefined modem command, in a data modulation format containing facsimile information to a remote facsimile modem, said remote facsimile modem being a PSTN-side facsimile modem of a back-to-back modem pair at a mobile switching center in the analog cellular network.

2. The method of claim 1 wherein the predefined modem command is an "AT-compatible" command.

3. The method of claim 1 wherein the step of classifying includes the steps of:

identifying the predefined modem command as remote if the predefined modem command is associated with a facsimile operation; and

identifying the predefined modem command as local if the predefined modem command is associated with a non-facsimile operation.

4. A method for establishing a facsimile telephone call over the analog cellular network to an opposite endpoint, the method comprising the steps of:

detecting in a modem a start of the facsimile telephone call;

switching to an extended mode of operation;

classifying subsequently received "AT-compatible" commands as local or remote;

operating on those subsequently received "AT-compatible" commands classified as local; and

transmitting, in a data modulation format, those subsequently received "AT-compatible" commands classified as remote, said commands containing facsimile information, to a far-end modem, said far-end modem being a PSTN-side facsimile modem of a back-to-back modem pair at a mobile switching center in the analog cellular network.

5. The method of claim 4 wherein the classifying step identifies those subsequently received "AT-compatible" commands associated with a facsimile operation as remote and any other subsequently received "AT-compatible" command as local.

6. Data communications equipment apparatus comprising:

a data terminal equipment port for receiving signals representative of a sequence of modem commands; and

a processor for classifying each modem command of the sequence into either a local command or a remote command and for operating on those modem commands of the sequence that are local and for communicating those modem commands of the sequence that are remote, in a data modulation format containing facsimile information, over the analog cellular network to a remote far-end facsimile modem, said far-end facsimile modem being a PSTN-side facsimile modem of a back-to-back modem pair at a mobile switching center in the analog cellular network.

7. The apparatus of claim 6 wherein those modem commands of the sequence classified as remote are associated with facsimile transmission and those modem commands of the sequence that are classified as local are associated with data transmission.

8. Data communications equipment apparatus comprising:

means for receiving a data signal representing a predefined modem command;

means for classifying the predefined modem command as a local command or a remote command;

means for operating on the modem command if classified as local; and

means for transmitting, in a data modulation format, the modem command if classified as remote to a remote facsimile modem, said command containing facsimile information, said remote facsimile modem being a PSTN-side facsimile modem of a back-to-back modem pair at a mobile switching center in the analog cellular network.

9. The apparatus of claim 8 wherein said classifying means is configured so that the predefined modem command is classified as a remote command if associated with facsimile transmission and as a local command if associated with data transmission.