Telebit Corporation

Canon Kabushiki Kaisha

Canon Inc.

Dirk Hughes-Hartogs

Dwight W Decker

Frederick L Mueller

Payne Freret

Mark B Flowers

A digital telephone (60) comprises send equipment (40) and receive equipment (50), coupled via a signal splitter/combiner (61) onto a digital telephone line (62) for communication with a remote party (90). The send equipment (40) comprises an A-law map (12) and a mu-law map (43). Receive equipment (50) comprises an inverse A-law map (14) and an inverse mu-law map (52). Maps (12,43) are selectable by the user (80). Similarly, inverse maps (14,52) are also selectable by the user (80). Receive equipment (50) may further comprise an un-quick-fix module (55) for removing unwanted insertions of quick fixes (25) inserted into the telephone line (62) by international telephone companies. Receive equipment (50) may further comprise a digital signal processor (57), computer (56), a set of pre-stored templates (58) corresponding to possible incoming telephone characteristics, and a caller parameter decipher module (51). In a preferred embodiment of a digital telephone receiver (50), an adaptive expansion table (95) is used to expand the digital signal at the receiver (50) from a relatively coarse resolution to relatively fine resolution. The configuration of the adaptive expansion table (95) is commanded by a control computer (99). Computer (99) is responsive either to a human control operator (80) or to statistics gathered by a statistics gathering module (97). The set of statistics to be gathered by the module (97) can be established by configuring a set of voice and data parameters (98).

Adaptive expansion table in a digital telephone receiver

Apparatus for efficiently routing facsimiles to and from a plurality of facsimile devices (62,64,66). At least one BRI line (16) is coupled to several ISDN terminals (21-28). At least one multiplexer (31,32) is coupled to the outputs of the terminals (21-28). A fax server (50) is coupled to the outputs of the multiplexers (31,32), typically via fax process computers (41,42). Coupled to the fax server (50) are a plurality of facsimile devices (62,64,66), each having a unique fax number. A given facsimile device (62,64,66) may send or receive more than one facsimile simultaneously by means of programming its fax number into more than one terminal (21-28) address. A terminal (21-28) may be coupled to more than one multiplexer (31,32). Multiple BRI lines (16) may be used. The fax server (50) preferably contains an incoming generic module (51) that interacts with all incoming facsimiles, an incoming specific module (53) that interacts with facsimiles destined for selected ones of the facsimile devices (62,64,66), an outgoing generic module (52) that interacts with all outgoing facsimiles, and an outgoing specific module (54) that interacts with outgoing facsimiles that emanate from selected ones of the facsimile devices (62,64,66).

ISDN fax routing

Apparatus for efficiently routing facsimiles to and from a plurality of facsimile devices (62, 64, 66). At least one BRI line (16) is coupled to several ISDN terminals (21-28). At least one multiplexer (31, 32) is coupled to the outputs of the terminals (21-28). A fax server (50) is coupled to the outputs of the multiplexers (31, 32), typically via fax process computers (41, 42). Coupled to the fax server (50) are a plurality of facsimile devices (62, 64, 66), each having a unique fax number. A given facsimile device (62, 64, 66) may send or receive more than one facsimile simultaneously by means of programming its fax number into more than one terminal (21-28) address. A terminal (21-28) may be coupled to more than one multiplexer (31, 32). Multiple BRI lines (16) may be used. The fax server (50) preferably contains an incoming generic module (51) that interacts with all incoming facsimiles, an incoming specific module (53) that interacts with facsimiles destined for selected ones of the facsimile devices (62, 64, 66), an outgoing generic module (52) that interacts with all outgoing facsimiles, and an outgoing specific module (54) that interacts with outgoing facsimiles that emanate from selected ones of the facsimile devices (62, 64, 66).

A digital telephone (60) comprises send equipment (40) and receive equipment (50), coupled via a signal splitter/combiner (61) onto a digital telephone line (62) for communication with a remote party (90). The send equipment (40) comprises an A-law map (12) and a mu-law map (43). Receive equipment (50) comprises an inverse A-law map (14) and an inverse mu-law map (52). Maps (12,43) are selectable by the user (80). Similarly, inverse maps (14,52) are also selectable by the user (80). Each of send equipment (40) and receive equipment (50) may further comprise an un-quick-fix module (45) for removing unwanted insertions of quick fixes (25) inserted into the telephone line (62) by international telephone companies. Receive equipment (50) may further comprise a digital signal processor (57), computer (56), a set of prestored templates (58) corresponding to possible incoming telephone characteristics, and a caller parameter decipher module (51).

Digital telephone overcoming international incompatibilities

Apparatus for sending and receiving both analog and digital information from a single information transmission medium. The apparatus includes a core processor (200), including a digital signal processor (DSP) (212) or a CPU/DSP, in communication with an integrated services digital network (ISDN) interface (204). The core processor (200) also may be in communication with a personal computer (PC) (202). The invention also is directed to a related method, including a series of modules.

Transmission of analog and digital information across a single line

A digital data base 10 having record data codes representing an initial digital record is printed at predetermined code sites 12 within two dimensional code storage area 14 on the surface of on base medium 10B. The digital data base includes redundant check codes and one or more redundant check-check codes for permitting data error and data loss correction. The two dimensional code storage area has a coordinate system for defining code positions therein. The code sites are physically positioned within the code storage area at predetermined coordinates. A plurality of error checking sets are formed by the code sites, each containing one or more data codes and one or more check codes. The bits in the check codes in each error checking set are determined by the bits in the data codes of the same error checking set, and are in error correcting relationship therewith. Each data code and each check code are included in 'L' error checking sets to provide 'L' levels of inter-locking error checking and correcting. In addition, a of plurality error checking-checking sets are also formed by the code sites. Each error checking-checking set contains one or more check codes and one or more check-check codes in error correcting relationship therewith. Each check code and each check-check code are also included in 'L' error checking-checking.

Error and loss correction in a data base stored on a two dimensional

A two dimensional row and column based system for storing digital data is formatted on a suitable base medium such as paper sheet 10. The data format is formed by a plurality of data units 10U having L data entry locations 14. The data is contained in the selective presence or absence of recording ink within the locations. Each data unit extends R locations along the row axis and C locations along the column axis. Any E entry locations of the L locations within the data unit are designated recording material present locations. The L-E remainder locations are designated recording material absent locations. The number of codes C that may be represented by these E in L type data units is determined by the relationship:

Ink intrusion resistant digital code

A high-speed modem that transmits and receives digital data on an ensemble of carrier frequencies spanning the usable band of a dial-up telephone line. The modem includes a system for variably allocating data and power among the carriers to compensate for equivalent noise and to maximize the data rate. Additionally, systems for eliminating the need for an equalization network, for adaptively allocating control of a channel, and for tracking variations in line parameters are disclosed.

Ensemble modem structure for imperfect transmission media

A high-speed modem that transmits and receives digital data on an ensemble of carrier frequencies spanning the usable band of a dial-up telephone line. The modem includes a system for variably allocating data and power among the carriers to compensate for equivalent noise and to maximize the data rate. Additionally, systems for eliminating the need for an equalization network, for adaptively allocating control of a channel, and the tracking variations in line parameters are disclosed.

The present invention relates to an apparatus and method for the simultaneous transmission of analog speech and modulated data, such apparatus and method being optimized for use over impaired and bandwidth restricted analog channels, or digital representations of such channels. In each instance of use, an evaluation is made of the available channel bandwidth, with a frequency division multiplex scheme allocating a voice sub-band, with data transmission allocated to sub-bands above, below, or around, this selected voice sub-band. The speech and data sub-band allocations are made by the multiplexor in response to user input of either a requested speech quality, a requested data rate, or a value indicating the relative user weighting of speech quality and data rate. A multi-carrier multi-mode modulation scheme is employed for data transmission, with this scheme having the ability to fully utilize the remaining bandwidth, and further, being capable of adapting to the impairments most likely present on the fringes of bandwidth restricted analog channels. When the analog channel employed is the standard voice-grade telephone circuit, good speech quality simultaneously with 3000 bps data transmission may be expected. The further ability to automatically switch to full bandwidth data transmission when voice transmission is not being attempted is also provided.

Speech and data multiplexor optimized for use over impaired and

A high-speed modem that transmits and receives digital data on an ensemble of carrier frequencies spanning the usable band of a dial-up telephone line. The modem includes a system for variably allocating data and power amount the carriers to compensate for equivalent noise and to maximize the data rate. Additionally, systems for eliminating the need for an equalization network, for adaptively allocating control of a channel, and for tracking variations in line parameters are disclosed.

Growing community of inventors

Morgan Hill, CA, United States of America

Dirk Hughes-Hartogs