Paradyne Corporation

At&t Bell Laboratories

Lucent Technologies Inc.

At+t Corp.

A.t. & T. Paradyne

Stanley Bottoms

William Lewis Betts

Gordon F Bremer

Kenneth David Ko

Luke J Smithwick

D Randy Roberson

Robert Earl Scott

Richard K Smith

Kenneth Martinez

Joseph Q Chapman

James L Korzik

William R Davis

Terrel W Sandberg

Guillermo Vega

An new cellular interface directly couples the speaker and microphone of a cellular telephone to a simultaneous voice and data (SVD) modem. This interface allows a cellular telephone user to use their cellular telephone for simultaneous voice and data communications over the cellular network. In addition, of the SVD modem has a port coupled to a switched facility of a switching system, this cellular interface allows the cellular telephone user to place a telephone call from their cellular telephone over the switched facility.

Cellular phone interface for a simultaneous voice/data modem

A simultaneous voice and data (SVD) communications system includes an SVD modem at either endpoint of the system. Each SVD modem provides an SVD signal to the opposite endpoint, where this SVD signal includes both a voice channel and a data channel. One, or both, of these SVD modems allows the respective user to alter either the voice signal that is provided to that user, or the voice signal that is transmitted from that user, via the voice channel of the SVD signal, to the opposite SVD endpoint.

Sound modification for use in simultaneous voice and data communications

A number of arrangements and methods that achieve concurrent communication of analog information and digital information. In general terms, when the communication channel is viewed as a multi-dimensional space, the digital information signal is divided into symbols, and the symbols are mapped onto the signal space with a preset distance between them. The analog signal, generally limited in magnitude to less than half the distance separating the symbols, is converted to component signals and added (i.e., vector addition) to the symbols. The sum signal is then transmitted to the receiver where the symbols are detected and subtracted from the received signal to yield the analog signal components. The transmitted analog signal is recreated from those components. Arrangements utilizing the above principles are applications where systems that include a digital port can benefit from an analog communication channel, and conversely, where systems that include an analog port can benefit from a digital communication channel.

Simultaneous analog and digital communication applications

A modem which represents the transmitted primary data stream using signal points selected via a trellis code is provided with the further capability of transmitting secondary data. In particular, a standard constellation of signal points is expanded to include a number of signal points which is greater than that needed to transmit the primary data. Particular primary data word values are representable by either of a predetermined pair of signal points associated with that value--one signal point of the pair being a standard signal point and the other being an expanded signal point. The specific one of the two signal points of the pair that is transmitted at any given time is chosen as a function of whether the value of the next bit in the secondary data stream waiting to be transmitted is a '0' or a '1'. The location of each expanded signal point in the constellation is selected such that its distance from the nearest signal point in the trellis code subset of its associated standard signal point is substantially at least as great as the minimum distance between any two signal points in that subset. Index values are assigned to the signal points of each subset in such a way that those index values change monotonically with increasing power of the signal points. Illustratively, in particular, the index values increase monotonically with increasing power of the signal points. Thus the signal point having the lowest power within a subset will have the lowest index value; the signal point having the second lowest power within a subset will have the second lowest index value; and so forth.

Index assignment in redundancy-coded data communication systems

A modem which represents the transmitted primary data stream using signal points selected via a trellis code is provided with the further capability of transmitting secondary data. In particular, a standard constellation of signal points is expanded to include a number of signal points which is greater than that needed to transmit the primary data. Particular primary data word values are representable by either of a predetermined pair of signal points associated with that value--one signal point of the pair being a standard signal point and the other being an expanded signal point. The specific one of the two signal points of the pair that is transmitted at any given time is chosen as a function of whether the value of the next bit in the secondary data stream waiting to be transmitted is a '0' or '1'. The location of each expanded signal point in the constellation is selected such that its distance from the nearest signal point in the trellis code subset of its associated standard signal point is substantially at least as great as the minimum distance between any two signal points in that subset.

Inband coding of secondary data

An apparatus monitors the convergence of the equalization training sequence in a multipoint communication network. Various latches record the period of the incoming sequence and the time to convergence, if any. A counter records the number of periods free of convergence, and upon the counter exceeding a threshold, the network train time is doubled. A register records the longest required time to convergence. This value is periodically compared to the network train time, and, if less, substituted therefor.

Automatic equalizer initialization time control for multipoint networks

A hybrid interface adapter is provided for interfacing a digital assembly to a standard data and control bus. The adapter includes level translating circuits for translating signal levels between the assembly and the control bus. The adapter also has a first port for connection to a bus through a standard connecter and a second port for connecting and mounting the adapter to the digital assembly.

Hybrid interface adapter

A selective secondary signalling encoder/decoder for multipoint data communications networks for use on transmission media such as telephone lines provides for selective signalling between a master broadcasting unit and however many slave units are in the network. The network functions by sending a standard (V-29) type modem training sequence and incorporating the address of the particular remote unit with which communication is desired in the data segment of the sequence. Compatibility is maintained with standard slave units that don't have this decoder by appending a sufficient number of marks to the address and message to allow for the standard starting value of a descrambler in the 'data mode'. When the segment is detected at each remote unit in the system, the address sent is compared to the address of the remote or slave unit. Upon a comparison match, together with a synchronism check and error checks, a valid message flag is set, indicating to the remote unit that it has received a command from the master site and thus the selected remote can be retrained or send a new sequence back to the master. Thus, instead of having to broadcast the same command to all remotes, individual remotes can be singled out to retrain back to the master so the time overhead in the network is significantly reduced since only one unit will be sending back training information to the master.

Selective signalling encoder/decoder for multipoint data communication

This invention discloses a demultiplexer with a first memory element for storing received data bits, a second memory element having individual cells connected to individual remote units (i.e. parallel output) and a logic unit for transferring the appropriate bits from the first to the second memory element in accordance with the received signal configuration. The enabling signal for the second memory element is derived from the demultiplex sync signal.

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Seminole, FL, United States of America

Stanley Bottoms