Nelson R Sollenberger: Equalizer with improved performance. American Telephone and Telegraph Company AT&T Bell Laboratories, David R Padnes, September 22, 1987: US04695969 (25 worldwide citation)

A technique for converging the tap-weight coefficients of an automatic or adaptive equalizer. The technique utilizes a training period during which time a plurality of identical signal sequences is transmitted. In the equalizer, during a training period, corresponding signal samples from the transmi ...

Robert L Cupo, Cecil W Farrow: Equalizer-based timing recovery. AT&T Bell Laboratories, David R Padnes, October 4, 1994: US05353312 (25 worldwide citation)

Timing recovery circuitry for recovering digital data generates a timing signal which is a function of the delay provided by an equalizer to one or more predetermined frequency components of its input signal. Advantageously, this approach is applicable to systems which utilize one or more baseband o ...

Paul S Henry: Zero disparity coding system. Bell Telephone Laboratories Incorporated, David R Padnes, January 5, 1982: US04309694 (25 worldwide citation)

In a digital transmission system, disparity is defined as the difference between the number of binary digits at each code state. The generation of a block of binary digits having zero disparity possesses many advantages. The present invention discloses coding apparatus (100, 300) for converting a bl ...

Arthur R Calderbank, Neil J A Sloane: Trellis coding arrangement. AT&T Bell Laboratories, Ronald D Slusky, David R Padnes, July 3, 1990: US04939555 (24 worldwide citation)

In a trellis coding arrangement, the alphabet is comprised of a plurality of cosets of a sublattice of a p-dimensional lattice, where p<4.

Donald R Green Jr, James P Moffatt: Distortion compensation for a microwave amplifier. AT&T Bell Laboratories, David R Padnes, July 30, 1985: US04532477 (24 worldwide citation)

Amplifier-produced distortion known as amplitude modulation to phase modulation (AM/PM) conversion is reduced through the use of GaAs FETs which are biased to generate AM/PM having an algebraic sign opposite to that generated by the amplifier. This algebraic sign reversal is accomplished by biasing ...

Joseph Q Chapman, Kurt E Holmquist: Call establishment for simultaneous analog and digital communications. AT&T IPM, David R Padnes, Patricia A Verlangieri, December 5, 1995: US05473675 (23 worldwide citation)

A modem, capable of simultaneously coupling voice and data signals, connects local digital terminal equipment (DTE) and a local telephone to a communications link. To prevent the local DTE from responding to a communications containing only voice signals, the local DTE is notified of an incoming com ...

Anthony Acampora, Ta Shing Chu, Corrado Dragone, Michael J Gans: Terrestrial communications system. American Telephone and Telegraph Company, Bell Telephone Laboratories Incorporated, David R Padnes, March 8, 1988: US04730310 (23 worldwide citation)

A terrestrial radio system which utilizes spot beams, time division multiple access and frequency reuse to provide communications services from a base station to remote customers within a system service region. The base station advantageously is arranged with multistage switching so as to permit the ...

Jean Jacques Werner: Multichannel multipoint network using time-division multiplexing incorporating a time offset for propagation delay. AT&T Bell Laboratories, David R Padnes, August 27, 1991: US05043982 (23 worldwide citation)

Time-division multiplexing (TDM) is used for communications between each remote location and the central location of a multichannel, multipoint polling network. Each remote location transmits data in a TDM frame which has predetermined time intervals for each channel or application. The duration and ...

David P Maher, Robert J Rance: Hybrid natural random number generator. AT&T Bell Laboratories, John Francis Moran, David R Padnes, October 1, 1985: US04545024 (23 worldwide citation)

A digital processor (16) is disclosed for improving the statistical characteristics of nondeterministic random-like binary sequence. The basic elements of the digital processor are a feedback loop comprising a delay (17) and a signal combiner (18) and a subsampler (19). Maximum performance of the di ...

Dan L Bisbee, Tingye Li: Automatic alignment apparatus for optical fiber splicing. AT&T Bell Laboratories, David R Padnes, October 2, 1984: US04474423 (23 worldwide citation)

Automatic apparatus for precisely aligning first and second optical fibers (11, 13) end to end. The first optical fiber is coupled to an optical source (12). An end face (15) of the second fiber abuts an end face (14) of the first fiber. Detector apparatus (16-19 or 51) affixed to the circumference ...