1
Michael D Turner, Kevin W Schneider, Richard A Burch, Richard L Goodson: Use of modified line encoding and low signal-to-noise ratio based signal processing to extend range of digital data transmission over repeaterless two-wire telephone link. Adtran, Charles E Wands, September 15, 1998: US05809033 (81 worldwide citation)

The range of digital data communication services, such as a basic rate 2B1Q ISDN channel, to customer premises located beyond the industry standard achievable range of a two-wire loop can be extended by increasing the capacity of the ISDN line code from two information bits per symbol to three infor ...


2
Michael Scott Sansom, Kevin W Schneider: Mechanism for providing emergency POTS service in event of loss of power to customer premises equipment for ISDN telephone lines. Adtran, Charles E Wands, August 24, 1999: US05943404 (69 worldwide citation)

In order to ensure continuous telephone service to a customer premises served by an ISDN line, without requiring that the customer maintain an additional POTS line as an emergency back-up to the normally used ISDN service, ISDN signalling circuits and network termination interface components are mod ...


3
W Stuart Venters, Kevin W Schneider: Transmission of encoded data over reliable digital communication link using enhanced error recovery mechanism. Adtran, Charles E Wands, February 23, 1999: US05875202 (67 worldwide citation)

In order to transport digital data across a reliable digital communication link from a transmit site to a destination site, the data is processed in parallel paths to derive error detection information, such as a cyclic redundancy code, and to encode the data. The outputs of the parallel paths are c ...


4
Daniel M Joffe, Robert E Gewin: Low distortion driver employing positive feedback for reducing power loss in output impedance that effectively matches the impedance of driven line. Adtran, Charles E Wands, January 5, 1999: US05856758 (67 worldwide citation)

A line driver with positive feedback reduces the output signal amplitude excursion required for driving a communication line, and enables the driver's output impedance to be synthesized using a reduced component value, thereby achieving a reduction in power loss through the output resistor, while si ...


5
Michael Scott Sansom, Robert James Toth: Method for increasing ISDN channel capacity of TDM serial communication link for digital subscriber line channels. ADTRAN, Charles E Wands, June 23, 1998: US05771236 (57 worldwide citation)

An overhead bit-usurping multiplexing/demultiplexing mechanism increases the overall effective ISDN channel-conveying capacity of a serial digital data communication link, and thereby enables a terminal site channel bank to provide ISDN service to an additional number of customer premises equipments ...


6
Kevin Wayne Schneider: Information communication system. Adtran, John A Fogarty Jr, Brumbaugh Graves Donohue & Raymond, June 12, 2001: US06246716 (56 worldwide citation)

The present invention is a communication system for communicatinginformation over greater distances than otherwise possible on bidirectional media subject tointerference, by reducing the interference while assuring spectral compatibility with other communication services. The system of the present i ...


7
Michael D Turner: Decision feedback equalizer employing fixed ratio postcursor taps for minimizing noise and intersymbol interference in signals conveyed over high speed data service loop. ADTRAN, Charles E Wands, October 1, 1996: US05561687 (53 worldwide citation)

The feedforward filter section of a decision feedback equalizer is modified to include one or more postcursor taps, that are sequentially weighted at decreasing binary fractions of the cursor tap. Such a modified feedforward filter section, combined with the placement of a simple anti-aliasing filte ...


8
Ralph R Boudreaux Jr, Steven M Robinson, John S McGary: Active ripple and noise filter for telecommunication equipment powering. Adtran, Allen Dyer Doppelt Milbrath & Gilchrist P A, December 3, 2002: US06489755 (51 worldwide citation)

An active tracking filter reduces low frequency noise (such as a 20 Hz ringing signal) riding on a DC voltage (e.g., on the order of (−40 VDC) applied to a load such as a subscriber line interface circuit (SLIC). A controllable impedance device, such as a FET operating in its linear range, is couple ...


9
Michael D Turner: Decision feedback equalizer employing fixed ratio postcursor taps for minimizing noise and intersymbol interference in signals conveyed over high speed data service loop. Adtran, Charles Wands, May 9, 1995: US05414733 (50 worldwide citation)

The feedforward filter section of a decision feedback equalizer is modified to include one or more postcursor taps, that are sequentially weighted at decreasing binary fractions of the cursor tap. Such a modified feedforward filter section, combined with the placement of a simple anti-aliasing filte ...


10
Fred Chu: Mitigation of non-linear signal perturbations using truncated volterra-based non-linear echo canceler. Adtran, Allen Dyer Doppelt Milbrath & Gilchrist P A, February 3, 2004: US06687235 (50 worldwide citation)

A non-linear echo cancellation scheme for a digital transceiver coupled to a wireline medium effectively mitigates against non-linear line perturbations that may cause disruption of digital communication services. A first embodiment employs a fast, linear echo canceler, and a truncated non-linear Vo ...